| | | In 2005-6 I became heavily involved in the revival to working order of a steam locomotive in Kenya, where I was living at the time. The loco had finished its days on permanent-way trains - the class was light on fuel and water which was an advantage when you might have to spend all day away from a water column. It was finally withdrawn and cast aside. Towards the end of the 1980s it was made ready for one last job, painted up as a 1920s loco for film work at Voi on the line to Moshi, with its oil fuel tank removed so wood fuel could be used. An unobtrusive diesel provided the actual motive power. The loco was then towed to Nairobi and dumped next the railway museum, where it mouldered until it was proposed as the third restoration project in Kenya Railways' steam tourism initiative in 2005.
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| A Uganda Railway EA3 class (later the East African Railway's 24 class) in service in the 1920s at the summit of the line to Uganda via Eldoret. |
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| 2409 in Nairobi Railway Museum, 2002 |
It was said that the boiler was in excellent condition. That turned out to be true - but almost everything else needed fixed! Seen against UK preservation projects which brought locos back from true scrap condition, the difficulties were trivial - except that the revival took place in a challenging working environment in the teeth of official indifference, and without much in the way of funds. This is the occasional diary I provided at the time to keep information flowing via a Yahoo e-group to a small band of supporters all over the world.
Graham Roberts
Wednesday 4th May 2005
4-8-0 tender loco 2409 (built as Uganda Railway No 170 by Vulcan in
1923) has sat cold and unloved in Nairobi Central Workshop since it was
moved there from the Museum last December. Lack of funding and labour,
as well as the general dip in morale as privatisation looms, prevented
progress.
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| Waiting for funding, shop 006, early 2005 |
I recently met the works manager and suggested that if he could reawaken
interest in the project, I would do what I could to find outside
funding for the supplies needed in restoration. He showed interest. We
shook the dust off the project folder and marked four initial stages:
replacement of stolen copper lubrication and air- brake piping; boiler
refurbishment; cylinder and side-rod refurbishment; and driving wheel
and brake rigging refurbishment.
We intended to spend today measuring up the amount of copper piping of
varying bores needed (the loco was lubricated purely by sight-feed and
oil-cup methods, no Wakefield or other pressure system). However, as a
side task, we tracked down KR's boiler inspector to 'book' his time for
an initial boiler inspection. After all if the boiler's no use, there's
little point in going further (there are five remaining 24 class boilers
in Kisumu and Mombasa, but they will be sold for scrap later this
month, and realistically it is most unlikely we will reboiler 2409).
The inspector duly turned up and said he could either make a visual
inspection of the boiler tomorrow at 0730, or we'd have to wait for
about a month. Oh, and could we please remove the steam dome, so he
could get a clear view inside? Joe Kamau was reluctant. I pushed him to
'go for it'... I soon found out why he'd hesitated!
I was vaguely aware that there must be something substantial underneath
the dome cover... after spending the afternoon helping the fitters
remove 34 three-quarter-inch bolts by hand, and then lift off the dome
forging using a block and tackle from the rafters of shop 006, I now
have a rather more intimate knowledge! Still, we finished the job
fifteen minutes after knocking-off time which wasn't too bad.
The main large missing item - the manifold turret which distributes
steam from the boiler to various ancillary uses for firing, lubrication
and braking - was resolved by recovering two suitable turrets (along
with several other useful fittings such as clack boxes, washout plugs
and gauge glass test cocks) from the Kisumu boilers when I visited a
couple of weeks ago. (More hard work in the sun with hand tools. I have
come to the conclusion that Vulcan Ltd. didn't want anyone to take their
locos to bits easily).
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| A 24 class main manifold (this one on 2401 in the Museum) |
Once we have the boiler inspector's opinion, I'll pass it on to the
group. Meanwhile, anyone visiting Nairobi is very welcome to bring a
boiler-suit!
Thursday 5th May 2005
Boiler Inspector Bushishi turned up as scheduled this morning and has
given quite an encouraging report from his visual inspection. He noted
the following:
Mountings:
Service both safety valves, service pressure gauges (and calibrate steam
pressure gauge), clean both water column gauge glasses, service clack
box, fit fusible plugs, fit main steam manifold
Firebox:
Repair brickwork, clean all tubes (flue and smoke), clean all plates
(crown, side, tube and backplates), caulk crownplate stays where showing
signs of leakage, service burner
Smokebox: thoroughly clean to remove carbon deposits and light carbon scale from tubes, tube plates and superheater header
Internally:
Heavily scaled internally. Thoroughly wash out and descale, if possible using chemical cleaner.
Bwana Bushishi also wants us to refit a standard-style EAR boiler
identification plate... I will try to get an authentic one cast in the
foundry using another plate as a pattern.
He'll reinspect the boiler in three weeks and follow up with a hydraulic
test. So we have, quote, a lot to do... Geoff, your boilersuit should
definitely be top of your packing list!
Friday 13th May 2005
This week's progress on 2409 (4-8-0 tender loco, Vulcan Foundry 3581 of
1923) is mainly about preparation. We have located almost all the
missing parts we need, including sufficient copper piping of various
sizes. The manifold turrets and clack boxes recovered from Kisumu have
arrrived and are being reconditioned. We had hoped to find a complete
small manifold unit with all the associated cocks and pipework (burner,
blowback, blower, etc) but have only been able to find the manifold
itself, so the pipework and cocks will be built up on this. A burner
control and stand have been found. A few small items are missing - some
control wheels for the rods which operate cocks on the manifold turret,
but these can be cast from scratch if necessary; and fusible plugs, but
these can be manufactured in shop 027, or failing that, purchased from
Timwood, the local boiler specialists, who have showed me round their
extensive stores. They seem to have most things! Apart from that, it is
still not certain whether we can get a large block of hardwood for the
front buffer beam from workshops stock, or whether one will have to be
purchased.
I have spent a couple of mornings this week getting truly filthy
cleaning the soot and light scale deposits in the smokebox and removing
old cementing. We'll clean the tubes on Monday and prepare the firebox
for the mason to repair the firebricks. A new boiler rating plate is
being cast in the foundry using an old plate (from 2406) as pattern, and
replica makers' plates are being machined after being very nicely cast
from a pattern made in the workshops using a rubbing of an original
plate (from another 1923-series 24 class) kindly sent by retired
EAR&H shedmaster Don Owens.
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| The replica boiler plates we cast in the foundry - the original plate we copied is on the right |
This is all very good news since it cuts down the cash required (since
Kenya Railways has none, funds will be raised from well-wishers, so
economy is important!). However, the workshops have no descaling
chemicals, and 2409's boiler is fairly heavily scaled. Given the time
wasted on 3020 with poor steaming, it seems sensible to make an effort
to give 2409 the best chance of steaming well from the start. However,
the boiler holds about 3500 litres when completely full, and local costs
for descaling chemicals are quite high - we will need $400 to $550,
depending on supplier, to treat the boiler. Can anyone with experience
offer advice here? Are there shortcuts or cheaper options, or is the
only way to bite the bullet and buy the descaling chemicals? Do we have
to use these at manufacturer's dilution recommendation (1:10) or can we
use a lower dilution for a longer period?
Next week should see more visible progress since the monthly 3020 trip
will be out of the way and more resources should be available for 2409.
The plan is to get lubrication and air brakes sorted out first, with
work preparing the boiler for testing going on in parallel.
Sunday 15th May 2005
From Roy Nelson:
In response to your request for suggestions for boiler de-scaling, I have a copy of Wheels & Paddles in the Sudan.
In it the author, Mr C.R.Williams writing of his time in the 1920's as
Assistant Mechanical Engineer in the Sudan Railways workshops in Atbara,
states that when he had problems with badly scaled boilers he tried out
a method recommended by the CME of the Malay States Railways.
Thus :- 'Obtain a quantity of eucalyptus leaves, macerate them well,
place in a large container and boil slowly for not less than four hours.
Strain off the liquid and add 1-1/2 pints to the boiler water of the
engine. Keep the dome cover off. Light up and maintain fire for 24 hrs.
Cool off and wash out thoroughly. Repeat if necessary.'
He performed the 'maceration' in Atbara by arranging two old 8" cog
wheels with a 4" face so that they were turned by hand and the leaves
fed through them from a hopper above. The method was found to be
successful so S.R. created a special plantation of eucalyptus and made a
habit of adding ½pt of the brew each time a boiler was filled.
Might this be a possibility for you ?
Sunday 15th May 2005
What a fascinating idea... and very suited to Kenya given the amount of
eucalyptus (blue gum) here, introduced from Australia to provide a
quick-growing source of wood fuel for the Uganda Railway.
The one snag is that we don't have a facility to keep water hot in the
boiler; there is currently no oil tank nor oil firing control gear on
2409 and we don't plan to fit them until after the boiler's viability is
proven. We can get hot water from one of the other locos though, and
the dome cover is off 2409 already (not a job I would want to do
regularly mind you!)
Maybe we can find a way. I suppose we could burn kuni (firewood) after
initially filling with hot water and washing out once to heat the
boiler. I'll discuss with the team tomorrow.... it's preferable to
spending $400, as long as it really does the job!
1.5 litres of macerated liquid doesn't sound very much (boiler capacity is 3500 litres)... did I get this correctly?
I'll keep you posted!
Thursday 19th May 2005
From Roy Nelson:
In response to your comment about the quantity, maybe it needs to be
borne in mind [a.] that the book is memoirs rather than a technical book
and that it was written in the mid 1980's describing life 60 years
earlier so maybe technical details would not have been recorded 100%
precisely.
Also [b.] that the author was describing re-habilitating loco that had
been put to one side even then so presumably they would not be new, and
thus may not have been as large as your loco. I'll also send a scan from
a NBL diagram book showing a typical SR loco that would fit into that
period and you can compare with what you have.
On the other hand if SR went to the bother of creating a special
plantation of trees then it must have worked for them to their
satisfaction.
Wednesday 8th June, 2005
Work on 2409 has been rather intermittent due to illness incapacitating
several of the old men of the steam team, and pressure of other work
keeping the central workshops' millwrights otherwise occupied. If you
are coming to Nairobi, bring a boiler suit, as Geoff Warren did last
week! Thanks Geoff for your help!
We have achieve the following to date:
Boiler:
Dome and main manifold removed, boiler tubes and flues blown
out, accessible scale mechanically chipped off, smokebox cementing
removed and metalwork descaled and cleaned, firebox scale removed and
cleaned. Still to be done: retube about six missing or faulty tubes;
re-cement smokebox; take down and rebuild firebox brickwork; caulk
leaking stays; re-fit washout and inspection plugs with new lead
washers, replace dome, blank off other orifices, and hydraulic
pressure-test the boiler to 215psi. (The boiler was last overhauled in
1971). If the pressure test is successful, we will chemically descale
the boiler and overhaul and replace fittings such as clack boxes,
manifold turret, safety valves, whistles, main steam slide valve, blower
and pump exhaust rings, and burner). We also need to service the
injectors and replace the stolen piping from injectors to clack boxes.
Lubrication:
Research has confirmed that we definitely need to refit pressurised
lubrication from the sight-feed lubricator to the cylinder check valves.
The Eureka lubricator has been removed for servicing or replacement,
and the cylinder wrappers and running plate sections removed to expose
the oil chokes and nipples. Still to do: refit lubrication piping to the
cylinders and the air pump, clean out and service all oil boxes; clean
out and service all oil sumps and keeps for wheel lubrication; fit new
flexible oil pipes for leading bogie journals to replace the present
rather inaccessible oil cups.
Tender:
Plans made to recover the oil tank from its current position in Voi.
Still to do: Some frame corrosion at the front may need attention. Water
tank to be opened, cleaned, and checked for leaks and displaced baffle
plates. Brakes to be serviced.
Cab:
New mounting made and fitted for burner pressure. Replacement small
manifold located. Old manifold locating studs cut away, new studs to be
fitted. Steam and air gauges serviced or replaced ready for fitting.
Still to do: service and fit small manifold and associated piping cocks
and firing control, find and fit oil heater, service gauge glasses and
test and drain cocks, fit steam generator and steam sanding piping and
cocks, fit gauges, service and fit air and steam brake controls and
piping.
Cylinders, motion, frames:
Not started. Lots to do!
Wheels and bearings:
Broken spring leaf on bogie noted for replacement. Lots to do, but the
main issue is whether the main bearings are in good order or whether the
metalling requires to be repaired on completely replaced.
Brakes:
Triple valve and equalisation tank removed for cleaning and servicing.
New brake blocks ordered. Still to do: service Westinghouse pump and
governor, brake rigging and blocks on loco and tender, service air brake
piping.
Electrical:
Not started. Generator requires overhaul, wiring system serviced, and a
leading marker light fitted. Electrical is an area of concern since the
workshops electricians have no knowledge of steam generator maintenance,
and we lost the steam team member (Mr Izini) who did the work
previously.
Cosmetic:
New maker's plates patterned and cast, and new numberplates and tender
lettering ordered. Still to do: fit these castings, clean and repair
previously primed surfaces, clean scrape and prime all frames (a task I
do not look forward to), apply undercoat and two top coats of paint.
Monday 20th June, 2005
Progress this week has been hampered by lack of materials but a rather rambling summary is below.
Boiler:
Firebox brickwork mostly taken down and a large quantity of rock-hard
carbonised sand removed. Another morning's work should see this
finished. Boiler inspector Buchichi confirmed firebox riveting and
plating is sound after hammer inspection. My previous report that we
need to replace six faulty tubes was mistaken, the holes in the smokebox
tubeplate for "missing" tubes are in fact threaded to take inspection
plugs, and all we need to do is find new plugs (said to be in the Museum
store) and replace them. Replacement water piping from injectors to
clack boxes has been located and annealed ready for fitting.
Boiler descaling:
Following eGroup member Roy Nelson's suggestion, I made up a small batch
of eucalyptus-leaf descaling liquid, as used on Sudan Railways in the
1920s. I will test this on lumps of scale from 2409's boiler to see if
it shows signs of softening it (the idea is to loosen the scale and then
wash it off, not to dissolve it). If it looks promising we will make up
a larger batch; if not, we will have to buy commercial descaling acid.
Still to do (boiler): rebuild firebox brickwork. Service damper
mechanism. Re-cement smokebox. Re-fit washout and inspection plugs with
new lead washers, fill boiler and identify leaking firebox stays, and
caulk them. Refit dome, make a pressure test fitting, blank off other
orifices, and hydraulic pressure-test the boiler to 215psi. Fix any
revealed problems, then chemically descale boiler and make a second
hydraulic test to check weak spots in descaled tubes. Overhaul and
replace fittings such as clack boxes, manifold turret, safety valves,
whistles, main steam slide valve, blower and air pump exhaust rings in
smokebox, and burner. Stamp and fit boiler inspection plate. Find and
fit new injectors, and water delivery piping to clack boxes.
Lubrication:
Some oil boxes removed for servicing. Copper piping for sightfeed
lubrication delivered and annealed ready for fitting. Awaiting acetylene
gas. Still to do: refit lubrication piping to the cylinders and the air
pump. Clean out and service remaining oil boxes and piping. Clean out
and service oil sumps and keeps for wheel lubrication. Fit new flexible
oil pipes for leading bogie journals.
Tender:
No progress. Still to do: Recover oil tank from Voi. Repair frame
corrosion. Water tank to be opened, cleaned, and checked for leaks and
displaced baffle plates. Brakes to be serviced.
Cab:
Old small manifold locating studs cut away, new studs fitted, small
manifold fitted. Steam, air and burner gauges received ready for
fitting. Still to do: acquire and fit piping cocks from small manifold
and firing control. Find and fit oil heater (a suitable scrap or spare
heater cannot be found, so we either have to adapt a different type or
remove the heater from 2401 in the Museum). Service gauge glass columns,
test and drain cocks. Re-fit steam pipes to small manifold and
lubricator. Fit steam generator and steam sanding piping and cocks. Fit
gauges, service and fit air and steam brake
controls and piping. Fit new cab seats.
Cylinders, motion, frames:
A start made in scraping and cleaning frames. Still to do: remove all
motion, check and where necessary replace bushes. Check wear on liners,
pistons and valves, packings, and cylinder bore.
Wheels and bearings:
No progress. Still to do: replace broken bogie spring leaf. Inspect
lubrication keeps for signs of melted whitemetal bearings and where
necessary drop wheels and repair or replace damaged metalling.
Brakes:
Equalising tank steamed out. Triple valve unserviceable, require to
locate alternative (perhaps swap with the unit on 2401). New brake
blocks ordered. Still to do: refit tank, triple valve and piping.
Service Westinghouse pump and governor. Service three air reservoirs.
Service brake rigging and blocks on loco and tender.
Electrical:
No progress. Still to do: overhaul generator and fit steam piping. Service all wiring and lights. Fit leading marker light.
Finish:
No progress. Still to do: fit replica maker's plates. Cast and fit new
numberplates and tender lettering. Clean and repair previously primed
surfaces, apply undercoat and two top coats of paint.
Tuesday 5th July 2005
Yet again, problems with getting gas for welding has prevented progress
on 2409's lubrication pipework. In addition, work on 5918 (replacing
broken firebricks, and overhauling the jammed steam brake on the front
engine) and 3020 (replacing brake blocks, and boiler washout) has taken
priority.
Anyway, back to 2409. I have now gained limited access to all the
original works drawings for 24 class locos (about 250 of them) and the
Sanctions for Alterations which document the minor changes made through
their sixty-year active life. The S for As however don't seem to cover
the major changes such as upgrading and moving the Westinghouse pump
from the right-hand side on the firebox to the left-hand side on the
smokebox in 1949, nor of altering the bulk of the class from coal fuel
to oil fuel in the early 1950s. Perhaps there is another class of
records I have not yet discovered. The original drawings are very
complete indeed, right down to the tools supplied with the original
locomotives. (I wish we still had these!) The drawings and S for As
solve some of the questions we had but not all.
Regarding the loco itself, I can report the following:
Boiler:
Firebox cleaned out, firebricks removed. Inspection plugs and mud doors
replaced with new lead rings. Two fusible plugs temporarily refitted to
make the firebox crownplate watertight. Boiler filled with water to
check for leaking stays; none were evident. There were signs of two
slightly leaking rivets in the front tubeplate, but this is not serious
to fix. Of course this is not a pressure test; we will descale the
boiler before getting to that stage. We need to heat the water in the
boiler when descaling and will need to build new firebricks in the
firebox first. We then have the choice of a wood fire, or retrieving the
tender oil fuel tank from Voi and refitting it along with a heater
(which will have to be cobbled up from one meant for a different class
of locomotive) and the associated pipework for the burner and lightup
cock. Since we will have to re- fit the oil tank at some stage anyway,
we will probably take the second route, if we can get the oil tank back
soon. Anti-vacuum (snifting) valve removed and cleaned; the valve
sticks, but we have a spare one removed from a 24 class boiler in
Kisumu, and will probably fit that instead. Still to be done: rebuild
firebox brickwork. Service damper mechanism. Re-cement smokebox. Descale
boiler using proprietary solution heated to 80 degrees centigrade for
at least 24 hours. Refit dome, make a pressure test fitting, blank off
other orifices, and hydraulic pressure-test the boiler to 215psi. Fix
any revealed problems. Overhaul and replace fittings such as clack
boxes, manifold turret, safety valves, whistles, main steam slide valve,
anti-vacuum valve, blower and air pump exhaust rings in smokebox, and
burner. Stamp and fit boiler inspection plate. Find and fit new
injectors, and water delivery piping to clack boxes.
Lubrication:
No progress. Still to do: refit lubrication piping to the cylinders and
the air pump. Clean out and service remaining oil boxes and piping.
Clean out and service oil sumps and keeps for wheel lubrication. Fit new
flexible oil pipes for leading bogie journals.
Tender:
No progress. Still to do: Recover oil tank from Voi. Repair frame
corrosion. Water tank to be opened, cleaned, and checked for leaks and
displaced baffle plates. Brakes to be serviced.
Cab:
Steam valves (6x 0.5", 2x 0.75", 2x 1") associated with small manifold
acquired. Still to do: acquire and fit piping cocks from small manifold
and firing control. Find and fit oil heater (a suitable scrap or spare
heater cannot be found, so we either have to adapt a different type or
remove the heater from 2401 in the Museum). Service gauge glass columns,
test and drain cocks. Re-fit steam pipes to small manifold and
lubricator. Fit steam generator and steam sanding piping and cocks. Fit
gauges, service and fit air and steam brake controls and piping. Fit new
cab seats.
Cylinders, motion, frames:
No progress. Still to do: Check and where necessary replace bushes of
motion. (We now intend to check for wear of each bush using a crowbar as
a lever, rather than removing all the motion; if we had more effort
available we would take all the motion down). Check wear on liners,
pistons and valves, packings, and cylinder bore.
Wheels and bearings:
No progress. Still to do: replace broken bogie spring leaf. Inspect
lubrication keeps for signs of melted whitemetal bearings and where
necessary drop wheels and repair or replace damaged metalling. We intend
to drop one axle only initially, then take a view whether we need to do
the other three based on the condition of its cannon-boxes and whether
we find evidence of damaged metalling in the keeps of the undropped
axles.
Brakes:
Equalising tank steamed out again, properly this time! Damaged flange of
triple valve built up by welding then turned to correct size. Valve itself
needs dismantled and cleaned, and we need to find a new gasket. New brake
blocks ordered, but it turns out the ones on 2409 are actually from a 60
class. Those on 2401 in the Museum are the correct type and we will remove
one so that the pattern shop can find the identical type in the pattern store
to cast from. Still to do: refit tank, triple valve and piping. Service
Westinghouse pump and governor. Service three air reservoirs. Service brake
rigging and blocks on loco and tender.
Electrical:
Generator removed and sent to electrical shop for servicing. Still to
do: fit generator steam piping and replace generator. Service all wiring
and lights. Fit leading marker light.
Finish:
No progress. Still to do: fit replica maker's plates.
Cast and fit new numberplates and tender lettering. Clean and repair
previously primed surfaces, apply undercoat and two top coats of paint.
Other:
Electrical welding set acquired and moved from shop 004 to steam repair area. Toolset acquired and locked up on footplate.
We need to find a way of increasing the work rate on 2409. The obvious
way is to get a few weekend work squads organised so that the
millwrights who are busy keeping the workshops running during the week
can concentrate on 2409. This will of course have a financial aspect,
and Kenya Railways is unlikely to make funds available. We will explore
other options after I return from a week's travel away from Kenya.
Tuesday 26th July, 2005
Progress has been difficult over the last few months due to competing
priorities during the working week for the millwrights' staff who
provide extra resource backing up the experience and skills of the small
team of retired fitters working on the three locomotives 5918, 3020 and
2409.
Help is at hand however! As you will have seen, several well-wishers
recently made generous contributions to 2409's revival, in response to
the appeal by Trevor Heath and Graham Kelsey. I am immensely grateful
for these since it allows us to run a program of Saturday work-ins, with
the millwrights and the retired men working together exclusively on
2409. The men receive a small honorarium from the revival fund and we
make significant progress on the project. We can also fund purchase of
consumables and spares not available within the workshops - KR is in a
cash crisis and cannot help with funding, and in any case procurement
takes months.
The first of these work-ins was on 23rd July and the following was achieved:
Water delivery pipes (two-inch copper pipes on each side of the loco,
from the injectors under the footplate along under the running board and
up to the clack box behind the chimney) cut, fitted and brazed in
place. Gaskets still to be fitted.
Copper piping from air pump governor to main air reservoir fitted
Piping from main air reservoir to cab control cock and then forward to front sand boxes fitted
Two new oil boxes fitted behind the front sandboxes, with syphon
trimmings and piping to direct oil to the piston rods. (Originally the
pistons are lubricated by hanks of oily worsted material secured so they
rest on the rods, and the oil boxes will supplement these).
Steam pressure gauge (an original EAR unit, recalibrated in the
workshops and with the correct working pressure of 165psi marked in red)
fitted in the cab.
Auxiliary steam manifold (small manifold in the cab which feeds a number
of auxiliary functions) prepared for cocks to be fitted. Lack of
suitable elbow joints (discovered at the last moment to be galvanized,
and unsuitable) prevented full progress.
Blower pipe prepared for fitting, needs to be annealed in the forge which will be done this week
In the preceding week, a start was made on renovating the electrical
wiring. The front headlamp now has a working bulb for the first time in
several decades! The Stones generator is being reconditioned in the
electricians' shop.
The millwrights' mason is collecting firebricks and cement from stores,
and he expects to make a start on rebuilding the refractory bricks in
the firebox this week. After this is completed, the cementing in the
bottom of the smokebox which protects the metal from overheating will be
replaced.
Chemical descaling of the boiler is yet to start, we want to wait until
we have made arrangements for heating to 80 deg centigrade using the oil
burner, which depends on completing the firebox brickwork and on
fitting a temporary oil tank if we cannot get the original tender tank
back from Voi in time.
We will also need to complete work on the small
manifold so that we can use the factory air supply for lightup
(atomising the oil in the burner) and for the blower, to keep the fire
going.
A new set of brake-blocks for loco and tender in being cast in the foundry and will be fitted when available.
A manifold turret (main manifold on top of the boiler, which on a 24
class is integral with the safety-valve casting) recovered from another
boiler is being reconditioned by the millwrights and will be fitted when
available.
Lubrication copper piping from the "Eureka" sight-feed lubricator in the
cab to the cylinders and piston valves on each side is to be fitted
soon, progress on Saturday was not possible since connectors of the
correct type had not been found. These will need to be made in the
turning shop before the next session.
We have yet to decide when the next work-in will be. It probably makes
sense to leave a gap while other work to be done during the week catches
up. I am going to be away from Nairobi for ten days at the Coast: my
wife has agreed to break the journey at Voi where I hope to make
progress on recovering the missing tender oil tank (I told her this
after she agreed to stop there!). Six months of pressure on KR to divert
the breakdown crane to lift this onto a wagon has borne no fruit; not
from any lack of co-operation, but simply because the single remaining
crane in working order was so overworked it could not be spared. Two
more cranes have now been returned to working order after a crisis in
which it became necessary to hire a crane from Uganda Railway
Corporation for a particular recovery (costly!).
Hardly a week now goes by without a serious derailment ("capsizement" as
they call it here) of a goods train somewhere on the system, due to
insufficient investment in track and vehicle maintenance. To further
increase crane availability, serious consideration is now being given to
reviving the 1926-built Tanganyika Railway 35-ton Ransomes and Rapier
4-8-4 steam crane EAR 1104, most recently based at Voi, which has been
out of service for several years. If this happens this will be the only
steam breakdown crane working in Kenya (perhaps in Africa?) and one of
the few from that era active in working service anywhere in the world; I
believe there is another one active at Tolosa in Argentina. (Three
Grafton two-ton steam cranes are still in the central workshops in
Nairobi, and one is still in working order; it is used from time to time
for moving wheelsets between CXR and foundry, and is fired with kuni
[wood] fuel).
Monday 1st August, 2005
I visited Voi last week and found to my relief that the tender oil tank
for 2409 is still intact, though marked for scrapping. There is a
promise that it will be loaded on a flat wagon this week when the
breakdown crane is passing by, but that promise has been made several
times before! More importantly, it is in good external and internal
condition and has been stored carefully (of course, since Joe Kamau was
the one who took it off 2409 in the first place).
Voi used to have three boilers sunk into the earth, from a 13, 24 and 60
class. The 60 class (6013) was moved to Nairobi last year and has been
renovated for use in the smith's shop of the central workshops. The 13
and 24 boilers are on the scrap list and have been dug up and put on
flat wagons preparatory to moving elsewhere.
Voi has a four-road running shed, still open but sadly more or less idle
now since the Taveta branch was mothballed about six months ago due to
lack of motive power for the twice-weekly passenger train. (The
preferred power was a 71 or 72, but only one of the these, 7105, is
still working and is currently working at Kilindini docks). A 62 class
is not a very satisfactory substitute since the branch has a ruling
gradient of 2.5% and a 62 has to work on full power for four unbroken
hours, which is not very good for it. Even on the heavily-graded Nanyuki
branch the grades are more balanced. Anyway, Voi's previous allocation
of a 72 and 62 has been withdrawn and the
shed staff are more or less without work.
This was to my advantage, since the two senior staff there had both
worked for Joe Kamau in the past and were pleased to hear of the plans
for 2409. They became very helpful. A rummage around the moribund stores
racks produced a few surviving steam spares - including two fusible
plugs for boilers which are like hen's teeth in Nairobi, as well as a
number of useful control valves and pipe elbows. The exhumed boilers
also had their fusible plugs still in position, so these were extracted
as well. The 24 boiler had its small manifold intact - another precious
item - which was easily removed as well. A little later, the whole lot
was in a cardboard box in my car (unbelievably given the usual
bureaucracy-mad KR setup) and I was watching a vast herd of elephants in
Tsavo East national park. Quite a successful morning!
The hope now is that the oil tank is loaded as promised and makes it to
Nairobi without further incident. This will be a major step towards
getting 2409 back to life.
Thursday 11th August, 2005
2409's new brake blocks have now been cast in the foundry. Two masons
will rebuild the firebox brickwork this weekend; the firebricks and
cement have been delivered to the steam shop. With any luck we will get
some of the lubrication piping completed next week.
Thursday 11th August, 2005
Regular readers may recall we need to descale 2409's boiler using
commercial descaling acid solution. We need to get on with this now.
Can anyone suggest how critical it is that we heat the boiler while
using the descaling liquid? The data sheet says the solution works
better when heated to 80 centigrade, but doesn't rule out lower
temperatures. I am wondering if we could achieve the same descaling
result with the solution at 15-20 centigrade for two or three weeks,
thereby avoiding the need to make the oil firing functional at this
stage and the cost of oil fuel (and nuisance of the smoke in the shed).
Anyone any thoughts, or even better, experience?
Friday 12th August 2005
From Trevor Heath:
My best advice is try it. Heating the solution will accelerate the
process. I'm not sure if not heating it will work but the chemicals will
be in the boiler and if the desired result is not forthcoming the
chemicals will be in there in any case for plan "B". I'm still not
convinced that a wood fire would cause damage to the firebricks, we are
not rolling down the track here. The wood could be placed carefully on
some temporary fire bars. As for smoke, push the nose of the loco
outside.
Saturday 13th August, 2005
From Johan van Veenendaal:
You can assume that any chemical reaction relies on four principles:
1. Reactivity of the chemical reagents;
2. Mechanical action, e.g. stirring of reaction solution;
3. Time;
4. Temperature.
To some greater or lesser extent, any one or more of these factors could
compensate for a lack of any one or more of them, within reason. As a
rough guesstimate, I'd say that you could get the 80degC results at
20degC in about 8-times the 80degC time. Probably would help if you
could shake the boiler around a bit in the process.
Let us know what happens. I assume you are now using the commercial
preparation, not the eucalyptus leaves?
Saturday 13th August, 2005
Yes, eucalyptus solution didn't seem likely to shift the scale after a
small test, so we will buy commercial chemicals. In fact the boiler is
not that heavily scaled, and we will probably get a fair bit out simply
by washing out now that it's been soaking for a few weeks.
Monday 15th August, 2005
Two masons worked on 2409's firebox brickwork over the weekend and
finished it last night. They did a very neat job. This is another
example of work that would not have been possible without the funds so
generously donated by eGroup members recently. Little by little, we'll
get 2409 back in steam!
The next priority is to finish the cylinder and valve lubrication
piping. If we cannot get the right people available during the week, I
will press to do this next weekend.
Sunday 21st August, 2005
This weekend's working party concentrated on the saturated steam elements of
the locomotive.
The main saturated steam manifold (manifold turret) of the loco is integral
with the safety-valve casting. We have a choice of five such castings: two
recovered from boilers in Kisumu, two from scrap dumps in Nairobi, and one
from 2409 as she came from the Museum. None was in perfect condition, but by
combining parts and some welding, a serviceable main manifold has been
produced with the traditional cocks-comb relieving lever for the safety
valves.
The main manifold is now in place above 2409's firebox, with the large steam
pipes to the injectors running down each side of the boiler, and the large
pipe running to the small steam manifold (auxiliary manifold) casting in the
cab on the fireman's side. The blower pipe from the small manifold along the
boiler to the smokebox is in place. The light-up cock connection has also
been completed. Only the pipes for the oil heater, oil tank blowback, and
burner atomiser from the small manifold needs to be done now, and these
await lagging and cladding of the oil heater (hopefully this week) and
arrival of the missing oil tank from Voi.
The main manifold casting weighs about 120kg by the way. No fancy cranes to
get it onto the firebox top; just a rope round the casting with a man up top
and two men heaving from below. Up it went!
The steam pipe from the main manifold to the sight-feed (Eureka) lubricator
is also in place. The condenser for the lubricator and the associated piping
has yet to be fitted, and the oil feed pipes from the sight-feed lubricator
to the cylinders, pistons, and Westinghouse air pump are next on the weekend
work list (as is the Westinghouse pump itself).
A whistle valve and whistle have been found and will be fitted to the main
manifold. Finally, the steam pipe for the Stones dynamo and for the boiler
pressure gauge will hopefully be added during the week.
The team this time was smaller: two fitters and a welder, plus myself on
Saturday only. This was more effective than a large party and will be the
preferred style in future.
Monday 29th August, 2005
There was no work party for 2409 last weekend, but the electrical fitter has
now completed refurbishment of all the wiring, switches, and Stones steam
generator. All have been tested and are satisfactory. With luck we will make
progress on the boiler this week, emtying it of water, refitting new fusible
plugs, then refilling and descaling. The oil tank still languishes at Voi,
so I went to see the CME about it today, and with luck he will get things
moving to bring it back to Nairobi.
Monday 6th September, 2005
A three-man work party last weekend made steady progress on 2409's
lubrication piping. The sight-feed lubricator now has pipes connecting it to
cylinder and piston valves (two pipes each side) and a fifth pipe to the
Westinghouse pump. The steam pipe for the latter is now fitted between the
manifold turret and the pump governor. The generator steam pipe and the
associated drain pipe is fitted. The air pipe for sanding has been relocated
to its correct position half-way up the boiler. The reversing control gear
and graduated brass plate (which had been damaged during an attempt to steal
it) was serviced and repaired.
The next work party will concentrate on reconditioning the Westinghouse
pump, fitting the check valves to the oil piping, and finishing a few other
tasks where connectors or elbows were not available.
Another task remaining is the oil heater (which requires lagged and cladded,
and fitted with associated pipework, some of which is missing and needs to
be found or fabricated). The oil tank is still in Voi.
Descalant for the boiler has been purchased and delivered and will,
hopefully, be used tomorrow after new fusible plugs have been fitted and the
mudhole door put back in place. I aim to soak the boiler with the descalant
solution for two weeks (cold), inspecting a test piece of scaled tube to
monitor progress. If boiler inspector Bushishi is also satisfied, we will
put the dome back on and hydraulically test in the last week of September.
If descaling is not completely successful we will add more descalant or heat
the boiler. (The commercial solution is designed for fast use - 24 hours -
in a working boiler, but it seems reasonable that it will also work more
slowly at lower than recommended dilution and temperature. It's a lot
cheaper and we're not in such a rush! We will see.)
Monday, 12th September, 2005
A three-man work party was busy on 2409 on Saturday. Pipe clips and
boiler mounting studs were made and fitted for all lubrication pipework, the
piston valve and cylinder covers were freed for removal on both sides, the
Westinghouse pump was partially dismantled for servicing, the steam pressure
gauge was fitted, and the lightup cock support bracket was fabricated.
Also last week the boiler descalant was added to a boilerful of water after
refitting the mud door and the two fusible plugs. We will see how things
look after a couple of weeks.
Next weekend we hope to progress further with 2409 : finish the Westinghouse
pump, start on the oil pipework, withdraw the pistons and piston valves for
inspection. We have found some oil heaters and oil control valves; we have a
burner regulator and, I think, a floor bracket for it. We have the swivel
joint which goes in the oil pipe between tender and locomotive. We are
missing the other steel piping parts and the reach rod from the burner
regulator to the control valve, but these can be fabricated. If we can find
check valve ball- bearings and springs we will finish the lubrication piping;
if we can find a test cock for the gauge glasses we will fit and finish the
associated drain pipes. The front and rear market lights need stands
fabricated. And that's before touching the brakes, motion, and wheel
bearings. Plenty still to do!
Friday, 16th September, 2005
Due to pressure of work from the freight train derailment and from steam
charter preparations, there will be no work party on 2409 this weekend.
However, one piece of very good news:: the tender oil tank, which I have
been trying to get moved from Voi to Nairobi for the last six months, has
almost miraculously turned up at the central workshops loaded on a flat
wagon. This removes one of the major uncertainties in the whole restoration
effort. We can now make progress with the oil delivery piping, heater, and
firing control, and if we need to light up the loco to help descale the
boiler, it will be feasible.
 |
| The tender tank - one morning it just turned up on a flat wagon. |
Sunday 30th October 2005
With the excitement of the RTC steam safaris behind us, work resumed
this weekend on 2409. The boiler inspector pronounced himself satisfied
last week with our descaling efforts, so a squad of four men spent
Saturday and Sunday preparing the boiler for hydraulic test, hopefully
in the coming week.
Preparation consisted of washing out the boiler thoroughly and re-
making the seals for the mud doors, and making and fitting blanking
plates for the main mainfold, clack box, main regulator valve, gauge
glases, and generator cock. We still have to remove an old weld on top
of the dome forging so that the threaded rod there can be removed;
normally this rod retains the dome cover, but for the pressure test is
removed to leave a hole which receives the adaptor for the pressure
gauge.
The hydraulic test consists of filling the boiler full of water until
it squirts out of the highest point (on top of the steam dome forging),
ensuring there is no air in the boiler. The calibrated pressure gauge
is then fitted to this point and pressure is introduced elsewhere - in
the case of this boiler, via a blanked pipe on the side of the firebox
wrapper which I think was formerly used for a superheater pyrometer.
Pressure is built up via a manual pump (manufactured in Kilmarnock,
Scotland); a squad of four is used with a long handle on the pump, turn
about, until the required test pressure (215 psi for a working steam
pressure of 165 psi) is reached without any leaks being apparent.
The squad who prepared the boiler will make their own test and remedy
any leaks before handing the boiler over to the inspector; they are
keen that it passes the test first time.
There are only four working days next week (Friday is a public holiday
for Eid al-Fitr, marking the close of Ramadan) so it is not certain
that we'll be able to finish the test, but we will try.
We also continued to overhaul the Westinghouse air pump, completely
disassembling the steam and air sides of the pump. The cylinders and
rings show little wear, and the inlet valve springs are in good
condition (important, since we have no spares) but the valves
themselves are corroded and will need to be replaced. The gasket for
the air cylinder lower cover is also broken. We can probably find these
parts in the steam stores, but there are also about fifteen scrap
Westinghouse pumps still lying near the works foundry, as a source of
last resort.
 |
| Servicing the Westinghouse pump. |
Thursday 24th November 2005
After a couple of weeks away, I paid a visit to Nairobi central
workshops yesterday to check on progress on 2409's boiler, which was
to be prepared for hydraulic test.
The normal procedure is for the boiler team to make their own
pressure test ahead of calling in the boiler inspector, to ensure
that everything is as it should be. The boiler is completely filled
with water, so that no air space remains, then pressure is applied by
a team of four men using a hand pump. Weak spots are soon exposed by
water leaks.
In fact, it took two weekends to get 2409's boiler satisfactorily
ready for its official test. The first weekend was spent checking and
remaking gaskets for the various blanked-off orifices which leaked
first time round when even slight pressure was applied. With this
done, pressure was taken up to 80psi, but the test plugs in the front
and rear tubeplates then leaked and had to be tightened. After that,
the pressure was taken above 80psi, but problems were encountered
with leaks from the large inspection door beneath the boiler. We had
not previously disturbed this door (about the same size as the dome
orifice; not to be confused with the small mud doors used for
washouts). Work was held over until the following weekend.
The inspection door cover is secured by nuts to a large number of
threaded studs in the boiler, like the dome forging. Removing these
took most of the weekend, they were rusted solid, and the large
air receiver on the running plate had to be removed to allow easier
access. The nuts were heated with a gas torch and eventually freed;
three studs were broken in the process and had to be replaced.
Once the door was off, it was possible to remove a large quantity of
scale and rust from the bottom of the boiler; the door's copper
gasket was removed for annealing and re-shaping, and a rubber gasket
fitted for the test. This time, there were no leaks; full test
pressure of 210psi was maintained. After two days this had reduced to
80psi. The boiler was declared ready for testing when the inspector
returns to Nairobi at the end of November.
The team decided to release remaining water pressure via the dome
forging where the test gauge was mounted. Muriuki was the man who
cautiously loosened the union, forgetting that the smoke cowl in the
shed roof was directly above him. The high-pressure water jet bounced
downwards from the cowl, dislodging years of oily soot in the
process, and Muriuki was drenched head to toe in cold wet filth. I
guess he will get someone else to do the job next time!
In between work on the boiler, the team also managed to complete
reconditioning the air pump, and lagged the oil heater ready for
cladding and fitting. The Eureka sight-feed lubricator in the cab has
been replaced with a new unit from stores. The connecting rods have
been dropped from the crossheads, to allow the pistons and piston
valves to be withdrawn once a special gudgeon pin with square threads
is made to help in the process.
Last weekend, attention was turned to the tender water tank. A large
hole was flame-cut in the tank top to allow a full internal
inspection. The external plates and internal baffles turned out to be
largely in good condition, with only light rusting (the baffle plates
have been renewed at some point in the tender's life). Several water
leaks were repaired, and the drain cock at the back, and twin feed
pipes to the injectors cleaned and serviced. (The latter revealed
that the control valve on one side was missing and the pipe blanked
off; presumably 2409's final duties on engineering trains at Voi took
place using a single injector. We will have to find and fit a new
valve).
The water tank is now ready for internal painting with bituminous
paint before new plates are welded on to the cut section. After that,
we will fit the oil fuel tank waiting in shop 010.
I hope that a new wooden front buffer-beam will be fitted next week,
as well as louvred cab side window shutters. If we have a work party
this weekend it will probably concentrate on the oil fuel feed and
the air brake reservoirs.
Monday 28th November 2005
Work continued this weekend fitting the fuel oil supply piping from
the tender to the locomotive, which was originally coal or wood
fired. The oil fuel system was installed in the late 1940s and was
supplied by Alco of the U.S. as part of the fleet-wide conversion to
oil firing of most EAR steam locomotives at that time. (Some 24s
based at Kilindini port were built as oil-fired locos, but not 2409).
A 2-inch steel pipe leads from the tender tank through a control cock
down to the tender frames and under the fallplate. Rigid pipes, not
flexible hoses, are used to bridge the gap from tender to locomotive,
with three flexible right-angle ball joints allowing flexibility to
negotiate curves.
Once on the locomotive, the pipe leads under the cab's left side and
up onto the running plate, into the oil heater (a steam jacket of
about six feet fed from the small manifold). The pipe then leads to a
blowback union (steam feed from the small manifold), and the firing
control valve (with a reach rod for control from the cab). The pipe,
now reduced in size to 1.5 inches, drops between running plate and
boiler to the burner at the front of the firebox, where steam from
the small manifold is fed to atomise the oil and blow it into the
firebox as a fine spray. Dampers at the front and back of the firebox
provide primary air for combustion and are controlled from the cab by
rods.
Everything is missing on 2409 apart from the burner itself and the
dampers. I am sure the Alco 24 class oil fuel system drawings must be
in the CME's drawing store somewhere, but we could not find them
where the index says they should be. Instead, the fitters made a
careful study of 2401 in the Museum, which has its oil firing system
complete.
A search of the steam stores provided an oil heater, the three ball-
joints, and the firing control valve. Steel piping of appropriate
size was also obtained with help from the head of the millwrights'
shop. A team of two fitters, a welder and a turner worked to
fabricate this into the shapes required, not helped by the lack of
pipe-bending equipment. By the end of the weekend, the job was only
about 50% complete, but at least it was the difficult 50% !
To finish the job we need to locate a blowback union, finish lagging
and jacketing the heater and fabricate new fixing clamps, fabricate
the run of 1.5-inch piping, fabricate the reach rod for oil control,
mount the firing control and its stand in the cab, and fit steam
piping from small manifold in the cab to the blowback union.
I am a little unclear on the precise functionality of the blowback
union. The idea of course is to allow steam to be blown back into the
tender oil tank to warm it or clear pipe blockages. In operation, the
firing valve is closed, tender control cock opened, then the control
valve at the small manifold opened so that saturated steam pushes the
oil back into the tank.
What I am naming the "blowback union" is a simple T-shaped union,
and it's not obvious on 2401 whether this has a nonreturn ball valve built
in to prevent hot fuel oil entering the steam pipe to the small manifold
control valve, or whether this is unnecessary. Probably one of the older
fitters will remember, or at worst we could take 2401 to bits to find out,
but perhaps one of the group members can advise what's typical practice
elsewhere?
Sunday 4th December 2005
A three-man work party spent the weekend completing the oil feed
arrangements for 2409.
The blowback union on 2401 in the Museum was dismantled during the
week and proved not to incorporate a non-return valve, which meant
there was no problem in sourcing a suitable part. The swivel pipe
link between tender and loco was also dismantled to check the exact
method of ball joint packing. Suitable packings were obtained from
stores.
The steam piping for blowback and burner atomiser has been connected,
as well as the oil bunker sludge drain piping. (The piping for the
latter was removed from a scrapped 87 class diesel, which is in a way
appropriate since the 87 concerned was manufactured by English
Electric at Vulcan Foundry, the birthplace of 2409). The furnace
control quadrant and stand, and the reach rod to the control valve
itself, were also completed. Still to complete at lunchtime today was
the assembly of these, repacking the swivel links for the oil piping
from tender to loco and adjusting to increase clearance above rail
level, and completing the lagging of pipework and the sheet metal
cladding of the heater.
The next job will be to manufacture a preheater for the oil bunker,
using a design sent by Ian McKay in New Zealand where they have been
fitted to several of their preserved locos. A hole will be cut in the
oil bunker allowing the preheater assembly to be fitted as a complete
unit (and removed easily for servicing, should it ever be necessary).
Once this is complete and the oil bunker is steamed out and checked
for leaks, we will be ready to fit the bunker to the tender. Before
that we will have to paint the inside of the water tank with
bituminous black paint and weld in new top plates where they were cut
away for access.
The boiler then needs to pass its official hydraulic test. After
that, blanking plates and rubber gaskets will be replaced by the
appropriate permanent fittings and newly-annealed copper gaskets.
Various steam pipe unions and details such as the condenser for the
sightfeed lubricator need finished off, and choke valves for the
sightfeed lubricator pipes need to be fitted. The injectors need to
be serviced and water feed piping fitted. The clack boxes and the
anti-vacuum valve need serviced. The smokebox cementing needs to be
replaced by the mason, the smokebox door sealing rope replaced, and
the pistons and piston valves need to be drawn from the cylinders and
inspected for wear, and most likely have their packings replaced.
At that stage we should be able to steam the loco for the first time,
although there is much finishing off work to do before it can move
more than a few feet. The blower ring needs to be removed, annealed and
replaced. The blast cap casting is broken inside the smokebox and
needs replacing if we can find a spare in the stores, or welded if
not. A broken spring leaf on the bogie needs to be replaced. The brake
rigging needs to be serviced and adjusted on loco and tender, and the
air brake receivers steamed out and replaced. The air brake regulator
needs to be fitted and the triple valve serviced. Lubrication oil cups and
piping need cleaning, and wicks and trimmings made and refitted.
Axlebox keeps need to be repacked with worsted material and filled with oil.
If the loco then shows it can start and stop itself reliably within
the confines of the workshop yard and no obvious mechanical problem
arises, we will aim to make a short test run to evaluate the
condition of the axlebox bearings, hornblocks and cheeks, motion
bushes, and valve settings. This will determine how much servicing
these components require.
In short, the more we do, the more there seems to be left to do! It
seems unlikely we will steam the loco this year, but it is reasonable
to hope we might do so in early January.
Monday 12th December 2005
Today was a public holiday in Kenya, Jamhuri Day, commemorating self-rule.
We took full advantage of this for three uninterrupted days of work on 2409.
We wanted to pass the boiler hydraulic test on Saturday, and
accordingly the
test gauge was mounted on the steam dome and the hand pump coupled up.
The
team of millwrights rather enthusiastically pressed the boiler to
250psi
before I arrived (210psi is the ordained test pressure, and 165psi the
working pressure). The pressure shown on the gauge fell back relatively
quickly however. There were no signs of leaking stays or tubes, so we
started to hunt for other problems. Two mudhole plugs were weeping
slightly,
and the inspection door below the boiler (or mud collector as the
fitters
call it) was also dripping. Not enough to really explain the pressure
problems though. Then, following up a tell-tale stream of drips, we
realised we'd completely forgotten to blank off the blowdown valve,
hidden
away under the boiler. Out of sight, out of mind!
The valve turned out to be tricky to remove: even after heating with a gas
torch, one stud out of the four securing it to the boiler was broken in the
process. Nothing daunted, the millwrights, well-used to broken studs on
recalcitrant old iron machines, welded on an extension to the stub of the
stud, heated the whole lot again with the torch, and succeeded in removing
it. It turned out to be just as well we took the valve out - it was badly in
need of servicing, and will now be much more reliable.
Once the blowdown valve was removed, a blanking plate and gasket was fitted
and the boiler brought up to hydraulic test pressure again. This time we
were successful and the test, holding full pressure for ten minutes and then
observing the rate of drop-off for the ensuing 24 hours, was passed.
Two machinists were meanwhile working away in shop 004 making the special
tool required to help free the piston rods from the crossheads. These are
secured by cotter pins, but the great force from the pistons ensures that
after a period of service, there is an immovable (and inaccessible)
interference fit between rod and crosshead which hammering will not budge.
The special tool operates on the same principle as a car jack. The gudgeon
pin, which links the small end of the connecting-rod to the crosshead, is
removed, the connecting-rod dropped, and the Walschaerts gear combination
lever separated from the union link so that the crosshead is not linked to
the piston valve spindle. It can then move stiffly with the piston rod given
a firm tug. A modified gudgeon pin is fitted, with a threaded hole bored
through it in the axis of the piston rod. A matching spindle is then screwed
in until it meets the end of the piston rod jammed into the crosshead.
Turning the spindle further presses the piston rod away from the crosshead,
breaking the interference fit. After this the piston slides smoothly in the
cylinder with hand pressure.
Square threads are required on spindle and pin to ensure the required force
(which is considerable - four men straining on long tommy bars) is
transferred properly. It took a day and a half to machine the tool from EN24
steel (the hardest we could get from stores), and a few anxious moments of
bent tommy bars and hopeful spraying of penetrating oil onto joints, but
eventually rod and crosshead parted and we were able to withdraw the piston
from the cylinder. The piston rings were removed from the piston and placed
back in the cylinder on their own. The end of the rings did not quite mate,
indicating they require replacement. However the piston itself and the
cylinder appear to be in good condition.
The piston valves, which we also dismantled, require new rings as well,
carbonisation from soot and oil sucked into the wrong places in the valve
would have made that clear even if the mating test had not, but again the
piston valves themselves look in good condition. We are hopeful of finding
the right size of new rings from the considerable range still in the
workshop steam stores.
In the meantime we also completed lagging and cladding the oil heater, and
serviced both injectors (the cones of which turned out to be in good
condition), and the water delivery cocks from the tender. The flexible
reinforced rubber water pipes linking tender and loco turned out to be
perished and will be replaced from stores. The anti- vacuum valve on top of
the superheater header was overhauled. The asbestos-rope packing between
valve casting and smokebox has dropped away resulting in a gap which will
destroy the smokebox vacuum. It will be replaced. Inside the smokebox, the
blower ring and brake pump exhaust ring were removed for cleaning and
heating to remove rust and scale. The blower ring had a large hole,
invisible before removal, which will be repaired with a welded patch.
We removed the steam dome cover (another four-man lift) and checked the main
steam valve's fit and operation from the regulator handle in the cab. The
old fitters pay great attention to adjustment of this valve: "the heart
of the engine" as they put it. Having seen 3020 hold a stalled train on
a 1-in-50 gradient by steam pressure on the pistons alone, when there was
too little boiler pressure to work the air pump for the train brakes, I can
begin to appreciate why one needs to have full confidence in this valve!
Finally, the inspection door / mud collector underneath the boiler was
removed so that the fitters could repeat their extraction magic on the three
studs broken when its gasket was replaced for the hydraulic test. This took
several hours of very awkward work, but was eventually successful.
The next work session will focus on servicing and re-fitting the various
boiler mountings with new gaskets and completing servicing of the cylinders
and pistons. The lubrication piping will be completed. The tender water tank
will be painted inside and left to dry until after Christmas, when we will
replace the top panels previously cut away for access. The preheater for the
oil bunker will have its design finalised and drawn, then will be
manufactured and fitted.
It's just over a year since Trevor Heath, acting on impulse, convinced Kenya
Railways' MD to move 2409 from the Museum to the workshops, and over six
months since I started the weekend work sessions after finally realising
that nothing would happen during the working week. In spite of progress
since then being in fits and starts, today was the first time I thought
seriously about ordering EAR maroon undercoat and topcoat paint for 2409. We
may just need it !
Sunday 8th January 2006
Happy New Year to those still reading these reports! Thanks for your
patience !
Saturday 17th December saw no activity since it was the day set aside for
the steam team's "Christmas Party". This year we widened the
invitations to include many of those who have helped in one way or another
but who don't actually work on the locomotive. We shifted a whole goat, a
fair quantity of beef, side dishes, and a not inconsiderable amount of beer,
sodas and for the diehards, local firewaters. (In case anyone is worried
their restoration donations are ending up as bottles of warm Tusker, I
should explain that Trevor and I funded the party, an annual tradition he
started three years ago).
For the record the Steam Team is:
- Ngahu (assistant supervisor, millwrights' shop)
- Ananda (millwright)
- Radero (turning shop supervisor)
- Ochieng (senior production engineer, locomotives)
- Osogo (foundry supervisor)
- Kamau (steam team leader and former senior technical inspector - retired)
- Nandwa (carpenter's shop)
- Odera (supervisor, painter's shop)
- Omondi (stabling fireman - retired)
- Ogutu (fitter - retired)
- Muriuki (millwright).
- Anyasi (supervisor, millwrights' shop)
- Mathuva (fireman)
- Mwoki (driver)
- Nyamae (fitter - retired)
- Ali (painter)
- Mekenye (mason)
- Warare (millwright)
- Buoro (locomotive inspector, retired)
- Wagura (senior production engineer - C&W)
- Thiga (foreman patternmaker)
- Gulale (turner)
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| The "steam team". Joe Kamau Gakunga in jacket, centre of rear row. |
Sunday 18th saw most of the steam team disperse for the Christmas break, but
a three-man team worked on removing the right-hand piston and piston valve
for servicing.
During the Christmas period, the inside of the tender water space was
sprayed with bituminous black paint. A search in the stores for new piston
rings and piston valve rings proved successful for the former, but oddly we
could not find any rings for the 24 class piston valves. (There are
literally hundreds of spare rings of other sizes). Instead, a suitable block
of cast iron will be cast in the foundry from which new rings of the correct
size will be machined. Another casting job will be to make a new blast cap -
the existing one is fractured in several places, and has been tack-welded so
that a pattern can be made from it for casting. A new mahogany buffer beam
was ordered from a timber merchant. Unfortunately it was substandard when
delivered, and has been returned. Once the correct item is available the
carpenters will prepare it for fitting to the locomotive. Other carpentry
jobs include new support blocks for the air reservoir between the frames,
cab floor repairs, cab window side screens, and rubbing strips between
tender water and oil tanks.
Work recommenced on Saturday 7th January. The new piston rings and pistons
were introduced to the cylinders and the cylinder covers replaced. The
cylinder cocks and pressure release valves were serviced and replaced. The
boiler was once again given interior proddings to remove remaining pieces of
scale and thoroughly washed out. The clack box was removed for servicing. On
Sunday, the dome cover was replaced with a new copper gasket and bolted
down; the mud collector door was replaced under the boiler, we modified a
copper gasket to fit, and the water delivery hoses from the tender to the
injectors were replaced. There was no time to replace the blower and air
pump exhaust rings in the smokebox. Both have been serviced, and the blower
ring sports a large patch welded over a rusty hole.
I hope we will steam out the tender oil tank in the coming week. A
replacement unit has been found in stores for the left-hand bogie spring
which has a broken leaf. This considerably simplifies the task since we can
simply put the spare spring in after jacking, and get the broken leaf
repaired at leisure. The blowdown valve has to be re-fitted, the sightfeed
lubricator condenser fitted, safety- valve/main manifold and clack-box
castings refitted, and a large number of small piping and rodding jobs
completed. The right-hand- side crosshead slipper needs remetalled on one
face, and we will probably find plenty other bearings and bushes requiring
attention. Overhauling the brake system is one of the bigger jobs still to
do. No doubt the list will get longer before it gets shorter.
Sunday 15th January 2006
The oil tank received a coat of red oxide primer during last week. It has
not yet been steamed out but with luck this will take place shortly. A
pattern for the cast-iron block for piston valve rings has been finished and
a pattern for casting a new blast cap was started. The wood for the new
buffer beam ahould be delivered on Monday 16th, and will be drilled and
prepared before being sent for creosoting at the sleeper works. (Although
most sleepers/ties used in Kenya are made of steel, wooden timbers are used
for points/turnouts/switches).
There will unfortunately be a delay in getting any further castings made,
since the foundry has run out of coal and the Supplies people have not yet
got the necessary three quotations before they can place an order. Not being
a coal-producing country, coal merchants are not exactly thick on the ground
here. The domestic cement industry uses some, as do (presumably) some
commercial foundries, but they may not be willing to sell some to Kenya
Railways. At worst, we may need to get the castings done commercially, which
will be expensive and will pose quality problems. The commercial foundries
typically do not analyse the metal composition of each casting run, since
most of them do not have laboratories. The railway's foundry sends samples
to the workshops lab as a matter of course. Some commercially-supplied wagon
brakeblocks recently turned out to be harder than the wheel tyres, so that
the tyres, rather than the blocks, were worn down in service. This is
precisely what we do NOT want to happen inside 2409's cylinders!
This weekend, the plate we cut out of the top of the tender water tank to
allow inspection and repair was welded back in. The blower and air pump
exhaust rings were repositioned in the smokebox. The front of the loco was
jacked up so the broken front bogie spring could be removed, unfortunately
the spare spring from stores was found to be second-hand, and to have damage
to its bolt holes, so the loco will remain on jacks until both springs can
be repaired.
Both crosshead slippers were removed. The whitemetalling on both is worn,
one badly, and will need to be renewed. The blowdown valve was re-fitted
below the boiler. The choke valves, three from stores, one from 2401 in
the Museum - were brazed onto the cylinder end of the lubrication pipes.
The main steam manifold was replaced on the boiler after a recalcitrant stud
was loosened by heating with a gas torch, and replaced. The various cocks
and unions leading from this manifold were removed and serviced, as was the
clack box. The anti- vacuum valve was re-fitted above the smokebox.
The coupled wheel brake blocks were removed, ready for the new blocks to be
fitted, the castings are nothing great and need quite a lot of fettling
before they fit the hangers neatly. A start was made on servicing the brake
rigging on the locomotive.
For some weeks, the brass numberplate and worksplate castings have also been
ready for finishing, but the machine shop has failed to find time for us.
The patternmakers, frustated at not seeing their work completed, finally did
the work themselves on their milling machine, after we built up metal over a
few minor casting flaws by brazing . They have made a very nice job of both
plates and finishing, and I am very happy with the result. It has to be said
that the Foundry team is a pleasure to work with, always supportive and
willing to help wherever they reasonably can given their "day jobs".
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| Crosshead slipper, and numberplates, cast in the foundry and machined by the patternmakers. |
It is now looking rather tight to steam 2409 this month, since we only
have two more weekends and we don't have any piston valve rings, but if we
get the oil tank steamed out and fitted back on the tender, we will not be
far off reaching that milestone.
Sunday 22nd January 2006
The tender oil bunker was steamed out to remove old oil during the week.
Fears of a coke shortage in Kenya proved groundless and the foundry is back
in operation. A hollow grey iron cylinder has been cast, from which piston
valve rings will be turned next week. A new blast cap has also been cast.
New crosshead guides were also cast in gunmetal, and machined. The
right-hand side crosshead turns out to have distorted jaws, presumably from
an impact at some time. We aim to bend it back into the correct alignment.
The new buffer beam has been delivered, drilled, and fitted to the
locomotive. It will now be removed again and sent to the sleeper works to be
treated with wood preservative.
The air pump was stripped again and inspected by an experienced man,
pronounced to be in good order, and reassembled. The piston valve spindles,
which for some reason were both badly "mushroomed" at the
combination lever end, were ground back to shape. Presumably they had been
"adjusted" with a sledge hammer at some point in the past. The
cocks and valves of the main manifold were repacked and refitted, and all
pipework connected. On top of the boiler, the clack box seating remains to
be tackled.
A start was made on freeing the cylinder cock rocker shaft. The reach rod
linking the firing control in the cab to the main oil valve was manufactured
and fitted. We have realised we have to remove both injectors in order to
service the water cocks, but had no time this week. We completed fitting new
brake blocks to the coupled wheels.
The coupling and connecting rods were removed from both sides of the loco.
The bushes are in good order on both sides, but the large securing nuts on
the left side are loose and need to be repaired or replaced. The
right-hand-side combination lever needs all three steel bushes renewed, as
does the associated radius rod bush.
The keeps under the coupled wheels' journals were withdrawn for inspection.
Unfortunately the news is not very good. Both the driving and trailing axles
show signs of damaged bearings so these two axles will have to be removed so
that the bearings can be withdrawn for repair. To do this we will have to
move the loco to the former steam loco erecting shop (010), where a
wheeldrop is still in working order (it is used for breakdown crane
repairs). This shop is intensively used for diesel-electric repairs so we
may not get immediate access. One of the underhung springs on the driving
axle is displaced and will probably need to be removed and serviced. More
bad news awaited us at the bogie: the side-control spring is broken and will
need to be replaced (a spare spring is thought to be available in stores), and the
spring above the bogie pivot is either jammed or broken. We will remove the
bogie while the loco is in shop 010. All in all this is quite a lot more
work than was anticipated and we cannot move the locomotive to 010 until the
leaf spring from the bogie is returned after repair.
We have still to complete overhaul of the brake system: steam out the air
receivers, check the triple valve and the steam and air brake application
cylinders before adjusting the brake rigging so everything operated
smoothly. No date set yet for first steaming.
Sunday 29th January 2006
Work continued on both Saturday and Sunday. The air damper at the rear of the
firebox was freed and its control rodding serviced. The cylinder drain cock
rocking shaft, which was jammed, was freed. The reversing mechanism was
partly serviced, the task cannot be completed until the valve gear is
reassembled after fitting new piston valve rings and rebushing of the
right-hand-side combination lever.
Pipework from the sightfeed lubricator to the air pump was completed, and the
lubricator condenser was fitted next the generator and associated pipework
completed. An attempt to remove the clack box seating by heating and
hammering was unsuccessful. Instead, we will remove the stands which secure
the clack box and grind the seating surface flat in situ. If the joint turns
out to be imperfect we will resort to making a puller tool.
The burner atomiser steam pipe was connected. A start was made on removing
and servicing all oil cups and associated lubrication piping - most are
blocked by years of dirt. Mr Mekenye, the mason, spent a day renewing the
cementing in the smokebox. Both injectors were removed and the water cocks
serviced. On inspection the injector steam cocks turned out to have no
functional parts inside their casings so these will require to be found and
fitted. The gauge glasses were prepared for refitting.
The grey iron casting for the piston valve rings was found to be too hard on
lab testing and it was realised a mistake had been made in material
preparation. A new casting was made on Sunday which will be sent for
machining into rings this week.
A blowhole in the blast cap casting, not thought serious enough to condemn
the part, was remedied by welding, and the casting was machined to take its
four teeth set in the blast. The teeth themselves were also machined.
A plan has been made to allow renewal of coupled wheel bearings at weekends
using the wheeldrop in shop 010, two axles per weekend. Due to pressure of
other work the locomotive will require to be towed in and out of shop 010
before and after each working session. The plan will be presented to workshop
management this week for their approval. (Shop 010 has seen activity seven
days a week for the last month-and-a-half, repairing the accident-damaged
9308 and 9315. Both had buckled main frames requiring major surgery. 9308 was
finally re- bogied early on Sunday morning and is now moving under its own
power. Work continues on 9315. We will have to ensure our use of the
wheeldrop and the overhead crane does not conflict with other activity).
With all other identified tasks included in the plan, and making the rather
large assumption that no delays occur due to dependencies on other workshops
activity, we will aspire to a first trial steaming of 2409 on 26 February. In
all likelihood this date will slip, but with luck only by a week or two.
Apart from refitting the oil bunker, remetalling the coupled wheel bearings
and servicing the bogie, servicing the brake system is the other major
outstanding task.
Sunday 5th February 2006
Two ten-hour work sessions on both Saturday and Sunday took place. My normal
team was busy on urgent maintenance elsewhere in the works, including a
weekend session aiming to get 3020 ready for trial on Tuesday. Instead, I
arranged for three of the breakdown crane gang to work on 2409. The crane
gang are part of the millwrights' shop, and crucially they are the last
regular users of the wheel drop in shop 010, the former steam erecting shop.
(The 75 ton Ransomes and Rapier crane, converted to diesel power from steam,
has a Stokes' Patent relieving bogie which needs the drop. It is the only
vehicle still to do so). The team was strengthened on both days by Fred
Anyasi, the foreman millwright, who has been very supportive throughout
2409's revival.
The wheel drop is a pit about five feet wide with a hydraulic jack (dating
from 1954) in it running on a short transverse track. The axle concerned is
positioned above the jack, which is then pumped up (oil hydraulics) to lift
the axle off its springs. The rail sections bridging the pit then have their
fishplates unbolted and are slid out of the way. The wheelset can then be
lowered and run sideways on the jack's transverse track for pickup by the
60-ton overhead crane.
On Friday afternoon I removed the brake pull rods under the coupled axles so
that there would be no impediment to dropping them. We left the coupling rods
in place for the shunt, since it is easier to adjust the position of the
wheels when replacing the rods at the wheel drop, using the overhead crane
rather than hand-pumped jacks.
On Saturday 2409 was shunted onto the large ("B") traverser at the
works and then to shop 010. We had expected this to be a short shunt to the
"A" traverser along a straight track, then final positioning into
shop 010 by winch. But the shunter had other ideas, and set off at a merry
pace with a string of wagons as well as 2409, to the other end of the works
sidings, from where we were propelled into the other end of shop 010. This
exposed some oversights in preparing the loco for movement. First of all the
equalising cylinder for the air brake, mounted under the right-hand-side
foot framing near the cab, started to work loose (it had been temporarily
repositioned after steaming out several months ago). The coupling rod started
to thump into the air cylinder at the top of each revolution. Eventually we
had to stop the shunt, quickly remove the cylinder, and throw it in the cab.
While we were stopped I noticed that the coupling rod retaining nuts had
almost fallen off, we'd removed the cotter pins to inspect the bearings, and
forgotten to put them back. Now the rods were catching the back of the nuts
as we ground round the curves. I put the cotter pins back in as best I could
and spent the rest of the shunt trying to spot loose nuts where they'd fallen
out again!
Once safely in shop 010, the coupling rods were quickly removed, and a start
made on dropping the driving wheels. The first task was to pump out the oily
sludge which had collected in the pit.
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| Removing the coupling rods. |
The 24 class has underslung springs and it took a little head- scratching and
false starts before we settled on the best way to proceed. Eventually we
realised we had to remove the split pins and loosen the nuts of spring
hangers and horn stays before relieving the weight on the axle slightly so
that the large pins linking spring buckles with axleboxes could have their
locking pins driven out and then be removed.
Removing all these pins (most of which were rusted in) took a long time, but
finally we were able to drop the springs using the jack to support them. With
these out of the way, the axle was jacked up, the rails removed, the axle
dropped, the rails replaced and the horn stays bolted back in position. It
was by then 6 pm on Saturday, but we had dropped the driving axle
successfully and taken it to the other end of the shops ready for
remetalling.
I believe this is the first time a coupled wheel axle has been removed in the
central workshops since the early 1980s. We moved and raised the loco when
necessary using the 60 ton overhead crane.
 |
| Removing the springs |
 |
| Jack supporting the axle, pit rail sections removed |
 |
| Dropping the driving axle |
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| Jack traversed to the side, allowing axle to be lifted away |
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| The driving and trailing axles |
On Sunday, we removed 2409's trailing axle by lunchtime, leaving only the
leading and intermediate wheels in place. We then proceeded to remove the
bogie. We had intended to do this using the wheel drop, but found out the
hard way the bogie was too long for it. You're right - a tape measure would
have saved the red faces.
Some further discussion ensued. Eventually, we removed the bogie pivot pin
nut over the wheel drop pit, then raised and packed the back of the
locomotive (so that the brake gear would not ground later on), before lifting
the locomotive at the front so that all coupled wheels were off the rails.
The bogie was left on the track.
It was then rolled forward out of the way, and the loco returned to a normal
angle, resting on a large packing block instead of the bogie. We had to
remove the damper control rods at the rear, and the headlight at the front,
to make space for the crane cables.
 |
| Removing the bogie. 60T overhead crane supports the loco. |
 |
| The bogie |
The plan is to remetal the bearings and then return the driving and trailing
wheels next weekend, before removing the leading and intermediate wheels in
their turn for servicing. We will also have to service the bogie, in all
probability including its bearings, since the oil cups look to be in poor
condition. Removing the coupled wheels has exposed many broken parts (spring
hangers, rocking washers, and so on) which would not have come to light
otherwise, so the exercise has to be worthwhile.
Sunday 12th February 2006
This weekend the new wooden buffer beam was fitted in place, sandwiched
between the two steel buffer plates on the front of the locomotive. The large
air receiver was replaced on the foot framing, and the copper piping was
removed and stored under lock and key (the loco is in a rather exposed part
of the workshops, and certain people find copper piping very useful for
making distilling equipment for chang'aa, or moonshine!). New mahogany
footboards were fitted in the cab. Meanwhile I worked away servicing the oil
cups and associated piping.
On Sunday, the oil bunker was fitted on the tender using the overhead crane.
This took a little time since a plate at the rear had to be removed, and then
the bunker offered up to the mounting brackets while suspended from the
crane. A new bracket had to be fabricated at the front, and tack-welded on.
The bunker was then removed and a proper welding job done. Finally, the
bunker was placed back on the tender to keep it out of the way during the
planned tour of the works by the new transport minister tomorrow. (These
tours are usually cancelled at the last moment, but at least it means the
workshops are tidied up from time to time).
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| Replacing the tender oil tank |
Earlier in the week the bearings from the driving and trailing coupled wheels
were examined more closely. They are quite badly damaged: two of the brass
shells have large fragments broken away from the edges, and one of the brass
horn cheeks is broken in two pieces. Since we don't know the condition of the
other two axles' bearings yet (they're still under the loco), it seems
prudent to manufacture new bearing shells and horn cheeks for all four axles
and replace the whole lot, given that they must all be fairly worn.
The pattern shop is up for the challenge, and I aim to find the drawings for
these parts next week so they can commence work. There will be a fair bit of
machining needed to finish the parts, always a bottleneck - but we will find
a way. One advantage of doing this is that it should be possible to service
the remaining two axles in a single weekend, since the new parts can be put
straight on. Meanwhile, the bogie is being thoroughly serviced in shop 005.
Monday 20th February 2006
Finding the drawings for 2409's coupled wheel axleboxes took some time. The
CME's drawing office store is a dusty, dark room with no electric lights,
full of broken furniture and abandoned files, in a neglected part of the
headquarters building. Older drawings, such as those for the 24 class
(delivered as the Uganda Railway "GD" class in 1923) are stored in
loosely-tied rolls, stuffed into shelves and prone to tearing and crushing.
Newer drawings (such as those for the 59 class) are at least kept in plan
cabinets.
The bundles of two hundred or so Crown Agents drawings for the 24 class were
easily found, but on extracting and examining the axlebox drawings it became
apparent something wasn't quite right. The axleboxes on the locomotive did
not match the drawings. So I had to go through the Sanctions for Alterations
files, where I pieced together the sequence of events. It seems the axleboxes
were redesigned around 1930 to simplify and no doubt improve lubrication.
After that the design was fiddled with every few years, a whole sequence of
alterations, until, I conjecture, post-war deliveries of new Tribal and
Governor class locomotives relegated the 24s largely to slow goods, shunting
and engineering trains. The design staff seem to have then lost interest in
marginal improvements in 24 class axleboxes!
Unfortunately, the Sanctions for Alterations referred to drawing numbers
which didn't seem to exist. They made no sense to the chief draughtsman. It
seemed we would have to make patterns for new castings by copying the worn,
old parts, not at all desirable.
Back in the workshops, I discussed the problem with the patternmakers.
They
turned out to have a card index of old patterns for steam loco parts,
which
some far-sighted individual saved (along with the patterns) when
disposal was
suggested after the end of steam in Kenya. Searching through this using
the
"missing" drawing numbers, I found the card for the axlebox patterns one
of which referred to "old" and "new" drawing numbers. This was the
missing link. Back at the drawing store, we were able to find the "new"
drawing number, and in the same roll, all the other missing drawings.
Even better, the patternmakers spent a morning searching their store from top
to bottom, and succeeded in finding the original patterns for the axleboxes,
keeps, bearings, and side and front slides. These were made for sizeable
production runs using shell casting technology, producing a casting needing
relatively little machining to finish, a great advantage to us. So now we
have drawings and patterns matching the worn axlebox parts, and we can see
that three sizes of bearings were used, depending on the amount of journal
wear in the axle.
We also know the exact alloy composition used for the castings (from the
index cards), and, incidentally, the last time the patterns were used, in
1971. We discovered that there should be leather gaskets for the steel dust
covers on the keeps. We will need a large number of castings: eight bearings,
sixteen side slides, and eight face slides for the coupled wheels, and four
bearings, eight side slides, and four face slides for the bogie. The patterns
have now been overhauled in readiness for casting. The electric elements in
the furnace for shell casting are broken, but we hope to get this repaired,
then cast and machine the new parts. Setting up the axleboxes will require
careful measurement of the horn faces in the main frames, to ensure
everything is square, but the retired fitters' experience will guide us
through
We also received the first few piston valve rings from the machine shop.
These are fitted to the piston valve by bouncing the ring on the ground so
that it splits; a half-round file is then used to shape the broken ends so
they fit the locating pin in the groove in the valve heads. Each head has
four rings, so sixteen will be needed in all, plus spares. Once the rings are
coaxed into position on the valve heads, the valve spindle can be slid into
the valve chest, using a sheet of paper to align the rings so they don't jam.
That's the theory, anyway! We hope to get the rest of the rings delivered in
the coming week, and fit the piston valves to the locomotive thereafter.
The bogie spent the week in a bosh tank, removing old oil and dirt using a
heated caustic solution. Now that it is clean, we can see that the side
control spring is not broken, it is in fact too short, and has obviously
been pressed into service using a couple of spacers and nuts to pad out to
the correct size. This it seems did not work well, since one of the side
control pins is broken, and the axlebox face slides are very worn. If we
cannot find the correct spare part in stores we will have to consider finding
the drawing and making a new spring in the smiths' shop.
During the week, the oil bunker was also given two coats of black enamel
paint. Work this weekend consisted of fitting wooden support pads for the oil
bunker, and completing the fuel delivery piping. We also started to
manufacture the oil preheater and its steam supply from the small manifold in
the cab, using a flexible Neoprene steam pipe to cross from locomotive to
tender. The limitations of my back- of-an-envelope/scrap material approach to
designing the preheater became apparent when we ran into some dimensional
problems, but we hope to overcome these and complete the preheater by next
weekend. We also completed the new blast cap, and I spent time trying to dig
nine inches depth of solid oily muck out of the enclosed area above the bogie
so the oil pipes can be serviced. Due to restricted access and poor lighting
and working position, this job is truly infuriating. I am sorely tempted to
ask someone else to have a go at it next weekend!
Further progress will now depend on delivery of the axlebox castings and
resolution of the bogie spring issue. We will then have to service the two
remaining coupled axles, put the copper pipwork back in place, and service
the brake system. It is unlikely we will steam the loco until well into
March.
Sunday 5th March 2006
The obstacle in the way of casting the brass parts for bearings and axlebox
slides turned out to be the heating elements in the oven for baking the shell
moulds not the non-ferrous furnace itself. The shell moulds are made by
packing a mixture of resin and fine silica sand between two mating patterns,
which are then baked in the oven before the mould is ejected from the
patterns using compressed air. The non-ferrous foundry has oil-fired and
electric (induction) furnaces, but only the oil furnace is in working
condition.
Finding suitable replacement heating elements for the oven at reasonable cost
took some time, but one oven was finally put in working condition. The shell
moulds can only be used once, so two men spent this weekend producing the 36
moulds for the side and face slides for coupled and bogie wheels. The
bearings themselves use conventional patterns in sand moulding boxes so no
shell moulds are involved. Hopefully the casting will take place early in the
coming week, followed by machining and whitemetalling. It is unlikely we
will be able to finish this before the weekend of 18/19 March.
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| The shell mould ovens. I found new heating elements at a domestic oven repair shop. |
Twenty piston valve rings have been turned, but cannot be ground to size
until the surface grinding machine is repaired. Meanwhile, other
miscellaneous jobs have been tackled. The clack box seating has been ground
flat and the securing stands replaced. Injector water and steam valves and
spindles/handles have been fitted. The preheater has been manufactured and
installed in the oil bunker, which has itself been installed in the tender on
wood packing. The pipework from the bunker has been completed. Both rear
sandboxes have been serviced. The six lubrication pipes for the front bogie
have been removed for servicing.
One unresolved problem is the bogie side control spring and side cheek. I was
unable to find suitable spares in the stores so we may have to locate the
drawing and manufacture new parts for these. This will be a priority next
week, starting by locating the relevant drawing.
Monday 13th March 2006
A start was made on casting the side and face slides for the coupled wheel
and bogie axleboxes during the week. Problems with power for the shell mould
oven meant the full number of slides, and the axlebox brasses, were not cast
until today (Monday).
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| Axleboxes showing liners and, behind, the shell moulds. |
Enough successful slide castings were completed last week to allow two men to
spend a full weekend machining the parts. They started by marking out the
castings according to the drawings and proceeded to remove the excess metal
using milling and boring machines. Problems soon became apparent. The
castings had much more metal to be machined away than is normal for shell
mould technology. Worse, it became apparent the slides could not be machined
to the correct dimensions without milling away holes cast into the part.
Something was seriously wrong.
I set up a long meeting to discuss this with the pattern-makers, casters, and
machinists, with the new cast parts, the originals from the locomotive, and
all the drawings available. Eventually, by removing the worn slides from the
bogie axleboxes, we became convinced that several detail modifications have
not been recorded in drawings or in the Sanctions for Alterations which are
meant to cover every design change. Either the system broke down almost
fifteen years before the end of steam - which seems unlikely - or there was a
practice of using older axleboxes modified to suit on individual locomotives,
without recording the details in records which applied to the whole class.
This detailed knowledge is presumably now lost, these patterns were last used
in the late 1960s.
Either way, we cannot machine the parts accurately using drawings alone
(apart from the face slides, which will need more machining than usual to
finish but should be usable). The side slides will have to be made to fit the
axleboxes, using a combination of measurements from the guides on the frames
and the axleboxes themselves to ensure a good fit. It remains to be seen
whether the axlebox brasses will also need modification. This is all very
disappointing and has been an expensive lesson. I am fortunate that the
foremen of the various shops concerned are keen not to be beaten by the
setbacks and are giving me their support rather than finding excuses to do
something else.
In some ways, it might be better not to disturb the side slides of the
axleboxes. After measuring the play between guides and side slides we will
review whether they are beyond scrapping limits or can be left for now. We
really have no choice with the face slides, which are very badly worn.
Fortunately they are the simplest to repair with new parts.
We still do not have an explanation for why the shell mould patterns
leave quite so much excess metal as a "machining allowance", well
over a centimetre rather than the customary few millimetres. The foundry
supervisor recalls that two decades ago, the practice was to use much larger
allowances, something he had to work hard to change. No wonder so many staff
were employed in the workshops formerly!
The surface grinding machine is still out of action. This is partly due to
electrical problems caused by the leaking workshop roof (the civil engineers
are meant to be fixing the roof, but at the moment work stops when it rains
due to the danger of electrocuting the machinists as water pours onto the
lathes, milling machines and grinder). However, the grinding stones are also
worn out and will be expensive to replace, several hundred UK pounds. New
parts were requisitioned several months ago but have not yet appeared. I will
try to get the head of the supplies department to help, but until then we
cannot grind the rings to repair the piston valves.
All in all, a very frustrating week, not helped by traffic jams that made my
usual thirty-minute trip to the workshops three times as long. The only
mildly positive development was the discovery (from the maker's drawings)
that the bogie side control spring should actually be two coil springs
face-to-face. This means I may have overlooked suitable parts in the stores,
I have been looking for a spring twice the correct length. Moreover, even if
we have to resort to manufacturing new springs, we now have complete and
detailed dimensions and test loads. Finally, Trevor Heath has reminded me of
the option of removing the springs from sister loco 2401 in the Museum, and
this may well be the best way to proceed; we would replace them with the
incorrect spring from 2409 so that 2401 could still be shunted if necessary.
I have checked 2401's bogie springs and they look good, although removing
them with the bogie in place will be hard.
Monday 20th March 2006
Last week, we measured the horn guides on the bogie and locomotive frames,
and soon came to the conclusion that there is variable wear on all of them.
We also realised that removing the worn liners from the axleboxes, and
machining and attaching new ones to fit, would take a long time.
We therefore decided on a new approach: we will repair the old liners in situ
on the axleboxes, building them up by brazing and facing off on the milling
machine to the original liner dimensions. We will then reassemble the
axleboxes and test clearances before finally machining the liners to suit the
worn guides. In one or two cases we will need to fit new liners, but it's
less work than replacing the whole lot.
The bogie axleboxes will have to be completed first since we cannot move the
loco back over the drop pit until the bogie is replaced. The bogie face
slides were therefore brazed up and faced this weekend; test assembly and
measurements from a datum will take place this week.
 |
| Brazing the face slides |
The axlebox brasses (half-shell bearings above the journals) have been sent
to shop 047 for whitemetalling. There is no coke for the furnace (again!) but
we hope to find a way round this shortly. Once the bogie brasses are
remetalled, scraped, and fitted, the liners machined, and the check spring
replaced, we can replace the bogie under the lcoomotive and start work on the
coupled axleboxes.
No progress on grinding the piston valve rings. More grinding will be needed
when we make new mild steel hub liners of the bogie and coupled wheels.
Monday 27th March 2006
Work progressed through last week and this weekend on the bogie axleboxes,
building up worn areas by brazing and machining to fit the axleboxes. The
axlebox brasses were cleaned of whitemetal and damaged areas repaired by
brazing. 2409's bogie side control spring was exchanged with the correct part
on 2401 in the Museum, an awkward job which took two men a whole day to
complete.
We need to decide whether to replace the hub liners (mild steel discs fitted
to protect the wheel hubs from wearing against the axlebox face liners). Some
of the hub liners are very worn, down to 2mm or 3mm from the original 9.5mm.
We have the choice of fitting new liners or building up the existing ones by
welding, but either way we will need to machine the surface true on a wheel
lathe. Neither of the two suitable wheel lathes in Shop 005 are operable. We
may be able to use one in the wagon shop; failing that we will not be able to
replace the hub liners.
2409 has been sitting in shop 010 blocking access to the wheel drop for
several weeks now. Inevitably, the one vehicle which still uses the drop (the
Ransomes and Rapier 75T crane) required attention after derailing last week.
2409 had to be moved about a locomotive length. Since the bogie and two of
the four coupled axles are missing, this was accomplished using two 60-ton
overhead cranes to relieve most of the weight of the loco so the packing
could be removed. The loco was then towed to its new position using the two
cranes in unison (alarmingly fast!) and the packing replaced.
Still no progress on grinding the new piston valve rings. We are
investigating whether this can be done commercially, but it seems few firms
in Nairobi have large enough surface grinders.
Monday 10th April 2006
Work on 2409 progressed slowly. Reconditioning of the side and face liners of
the bogie axleboxes is now almost complete. Some of the brasses were
remetalled, then the whitemetal shop ran out of coke. I was quoted 200
shillings per kg to purchase a couple of sacks from a local foundry. Foundry
coke costs about 10 shillings a kg free-on-board China. We needed at least
50kg. Fortunately the railway's shipment of coke was suddenly cleared through
Mombasa port, so I hope to avoid that particular expense. It seems that KR's
management had been comfortably assuming Rift Valley Railways would be
customers for brake blocks from the automatic casting line in the foundry,
which is not being concessioned. RVR, not impressed with KR's excuses for why
the foundry was not currently producing blocks, let it be known they were
pricing up procuring them from South Africa. Suddenly the coke shipment's
release was expedited ! We hope to have coke by the end of the week.
Last weekend we spent a day trying to coax the old wheel lathe back to life.
Although there are five or six other large lathes in the workshops, none have
toolposts able to do the work we want (trueing hub liners). After a lot of
oiling and fiddling, we had all motions of the lathe working under electric
power, and a bogie wheel mounted in the centres. Unfortunately when we tried
to actually do some turning, the multi-link flat drive belts proved to be too
slack to start a load from rest. There is no tensioning arrangement, and the
tool to remove links from the belt went missing when the lathe's operators
were retrenched a few years back. Apparently the workaround is to help the
lathe build up momentum by pushing the workpiece round by hand as speed
builds up. Sounds a good way to lose an arm. Unfortunately, unless we get the
lathe working, we will not be able to renew the hub liners and thus get the
correct side play in the wheels. Further study needed!
 |
| Building up a worn face liner by welding |
The search for a large surface grinder continues. The problem is that
commercial engineering companies do not have magnetic workpiece holders large
enough for the 9.5" diameter piston valve rings. However, the KR
procurement machine is churning slowly on, and we may yet get new grinding
segments for the KR surface grinder. Quotations for the parts (cost about $500) were to be opened this week.
We replaced the front buffer on 2409 this weekend as well, which will make it
easier to move once we have the wheels ready to go back under the engine. We
also replaced the coupled wheel axleboxes, with their reconditioned face
liners, in the frames temporarily so I could measure the face-to-face
distance. There is meant to be 0.250" total side play on each coupled
axle; unless we can replace the hub liners, we will not be able to reach
this, but it will be a great deal better than it was before servicing.
Sunday 17th April 2006
Minimal progress to report this week. We still await arrival of the coke
shipment from Mombasa, so no further work was possible on remetalling the
bearings. We were not able to get the wheel lathe to rotate by pushing the
wheelset to help it build up momentum; we have not finally given up, but I am
coming to the conclusion we will have to live with worn hub liners and
journals. No progress, either, on grinding the piston valve rings, but we did
prepare the valve heads, replacing a missing locating dowel. We did some
further work to repair side liners on the bogie axleboxes and adjusted the
fit of the right side driving wheel axlebox in the slides. Finally we removed
some of the right side valve gear for rebushing.
Monday 24th April 2006
Work this weekend consisted of replacing the lubrication cups and pipes for
the bogie and two trailing axles. The bogie axleboxes' fitting was completed
and a start made on rebushing the right side Walschaerts combination lever. A
few other odd jobs were dealt with. The reason for the breakage of
axlebox-to-spring pins on the coupled wheels is now apparent; the castings
which link the pin and the spring are worn unevenly so that the nine-inch pin
is not supported evenly over its whole length. The pin therefore cracks or
breaks in the middle. We will probably have to bore out the castings to
ensure a uniform fit and machine new pins to suit.
We await remetalling and scraping of the bearings, grinding of the piston
valve rings, servicing of the wheel lathe drive belts, and recovery of bogie
spring beams from the bosh tank, the same hold-ups which have applied for
almost a month now.
Tuesday 2nd May 2006
The cylinder and piston valve lubrication pipes were cleaned and annealed
this weekend, the fastenings for the cylinder wrappers serviced, and the foot
framing plates put back in position. The bogie spring side beams were
retrieved from the bosh tank and cleaned. Work proceeded in the machine shop
on making threads on new crankpin nuts for the coupled wheels, and on
rebushing the right side Walshaerts gear.
The wheel lathe was finally coaxed to work reliably by manufacturing a tool
to allow removal of two links from the flat drive belting. I had hoped to use
the lathe to true up the axle journals, which have coning of about 10 thou
and some pitting in places. The wheel shop staff advised however that axle
journals should be ground, not turned. To do this we would need to press the
wheels off the axles, which I think is too risky, since we have no new wheels
if the castings are damaged. Instead we used the lathe to polish the
journals with emery paper and to remove worn hub liners.
Unfortunately, when
we came to fit new liners and attempted to true them up using the lathe, it
became apparent that it cannot make any size of cut without the toolpost
moving, which of course makes it useless for accurate work. The solution is
to reduce the liners to size before fitting and take a light final cut with
the wheel lathe to true the liners. This is not ideal but should at least
result in the correct sideplay in bogie and coupled wheels. Two days were
spent dangling wheelsets from the overhead crane and getting used to the
lathe, fun, but also frustrating, and I am a bit disappointed we did not
achieve more with it. The automatic feed is faulty, seemingly due to a broken
gearwheel, which translates into scores and ridges when turning. It would
require quite a lot of servicing to be put back in good order.
 |
| Struggling with the wheel lathe |
 |
| Attempting to machine the hub liners |
I bit the bullet and purchased some foundry coke from an (expensive) outside
source. As a result the wheel brasses have been remetalled and will now be
machined and scraped to fit individual journals. I also finally found an
engineering works with a machine big enough to grind the new piston valve
rings and hope that this work will be done this week. I have been quoted some
truly frightening prices for doing the job, but I hope the firm concerned
will take a helpful view. Fingers crossed!
Overall progress has therefore been rather gradual, but I hope that the main
blockages have now been overcome and we will get the project moving forward
again. This week's puzzle is to find a brass union for the top of the
Westinghouse pump, none in stores and none in the local commercial boiler
suppliers.
From Stephen Gifford:
I remember reading an account of restoration progress on a UK preserved
railway (SVR?) in which the group wanted to true up worn and pitted
crankpins, but not being able to remove them, or having equipment to grind
them in situ, they made a two-part wooden frame with two handles, that
clamped over emery paper, wrapped around the crankpin. By rocking the frame
to and fro, they eventually achieved a suitable finish --- presumably after a
lot of effort, and with frequent pauses to dismantle and measure
roundness/parallelism.
That's basically what we did for 2409's journals, but of course rotating the
axle as we clamped the emery paper on, and wetting the emery with light
lubricating oil. The clamp - exactly as you describe, two handles joined by
a strip of canvas with a recess in each handle to take the axle - is used in
Nairobi to polish journals for diesels on more modern lathes. We found an
old one and adapted it for the steam loco axles. The result was quite good,
taking most of the corrosion pitting off the surface. Some deeper pits and
cavities are still evident and I suppose we will have to get the axles
tested by the lab for flaws. However, as long as we mark the pitted journals
and warn operating staff to check them rigorously for heating, I don't think
it will be a huge problem - there are no flats or seriously damaged areas.
The wheelshop staff say one way to deal with the pits is to smooth the edges
using a round-edged grinding stone, to reduce the tendency of dirt or grit
to catch in the hole rather than be washed out of the bearing.
We are lucky in that our crankpins are all in excellent order, so we don't
have to try polishing them - it sounds like it would take quite a while.
Monday 8th May 2006
A total of eleven men (plus myself) were working on 2409 this weekend and we
made good progress. (The eleven were three machinists, a crane driver, a
welder, four fitters, and two retired men to give us practical advice at the
sticky bits).
After a bit of practice the machine shop team became better at working round
the wheel lathe's limitations, and in fact succeeded in slimming the hub
liners to size wholly on the lathe with acceptable finish. We should now have
the correct sideplay of 1/8" each side of the wheelset.
The piston valve rings were duly surface-ground commercially for £4.00
each; we needed a total of twenty. I had hoped to get the work done for free,
but it is still a lot more reasonable than some quotations I was given. The
job was well done and held within the correct tolerance of plus zero, minus
two thousandths of an inch. The rings are then bounced on the ground to split
them, then a segment is removed so that they will just fit in the valve chest
liner, and a recess is filed to take the locating dowel in the valve head.
Each of the two heads in the piston valve is then fitted with four rings. So
that they can be inserted into the valve chest without jamming in the steam
and exhaust ports, it is necessary to wedge the rings hard into the valve
head slots using strips of paper. This simple-sounding operation turned out
to be very trying in practice, and we broke a couple of rings before we
really understood what we were doing. Since we have very few spares this was
bad news! Eventually we realised we must shorten a couple of the rings very
slightly to get them to sit flush with the valve head. By then it was almost
dark, so we stopped work on the valves and will start again next weekend. I
feel confident we will succeed however.
Rebushing of the Walschaerts gear was completed, and a start made on
machining the white-metalling of the bearing brasses. The latter will take
some time and will be followed by scraping so they fit the journals
precisely. Then we will be able to reassemble the axleboxes and put the
wheels back under the loco. The copper lubrication piping, which we had
removed and stored for security, is now half refitted (and rather more
carefully than before) after annealling. We also started to overhaul the
brake system under the direction of a retired fitter; the driver's brake
valve, triple valve, governor and Westinghouse pump top head were all
examined and serviced, and a suitable part found for the missing brass union
from the top head. The actuating cylinders on loco and tender will now
require to be dismantled and serviced.
A couple of weeks more work is probably needed before we can get the bogie
coupled wheels back under the loco, and then we will have to service the two
remaining coupled axles (leading and intermediate). After completing the
lubrication piping we will need to refit the crosshead slippers with their
new liners and refit the piston valves, valve gear and side rods. In
principle we can then steam the loco.
Sunday 14th May 2006
Due to 3020's Saturday excursion (which incidentally attracted a
creditable 82 passengers), the millwrights who do most of the work on
2409 were busy that day. However, work continued on machining journal
brasses for eventual refitting to the axleboxes. I hope this will be
possible in the next two weekends.
Today (Sunday) the remainder of the pipework on the locomotive was fitted
complete with gaskets and seals. Only the clack box and large manifold now
require gaskets. One of the steam cocks for the injectors was dropped and
will require replacement. An extra tool locker for the locomotive was also
welded up from steel sheet offcuts, courtesy of the rebuild of
diesel-electric 9315 damaged last year in a head-on collision. There are
already four lockers on 2409's tender but my view is that you can't have too
many!
After seven hours of struggling we finally got one of the piston valves back
into the valve chest in one piece. So much for my confidence last week that
we knew how to do it ! The lessons learned were that ring size is critical,
and alignment of the valve heads to prevent ring ends dropping into the
steam ports and breaking, similarly so. However, we took these lessons to
heart, and succeeded in getting the other piston valve back in on the first
try after only three hours, finishing by torchlight at 1900. We broke all
but one of our eight spare piston valve rings as part of our learning curve,
and we cannot easily manufacture more, so I was on tenterhooks by then.
Next jobs are to machine and replace the slidebar brass liners and
remetalled slipper blocks, re-erect the valve gear, replace the bogie and
two coupled axles, drop the other two coupled axles for inspection and
possible repair, and finish overhaul of the brake system (service the brake
actuating cylinders on loco and tender, and finally replace the dismantled
brake rigging under the loco).
Monday 22nd May 2006
On Saturday we re-erected 2409's bogie. I had expected this would only take a
morning, in fact it took all day, mainly due to the need to use an angle
grinder to grind the sides of the keeps so they would fit in the axleboxes.
Building up the face liners by brazing must have distorted the axleboxes
slightly.
On Sunday we put the bogie back under the locomotive and started to
reassemble the exleboxes on the driving and trailing axles in readiness to be
put back into the frames. Further work took place on gaskets for boiler
mountings and on fitting the gauge glass cocks and columns. Since there are
no suitable (Klinger AB18) sleeve packings for the gauge cocks in stores I
was forced to buy some locally, about £13 each, and we needed eleven of
them (five for each column and one for the whistle). If anyone has a
significantly cheaper source abroad I would be interested to know, but as far
as I can see from the Internet they would cost at least £8-£9
over the counter in the UK. Those I could find here were imported from UK but
are not good quality.
I suppose anyone used to steam preservation elsewhere in the world will find
this a trivial amount of money, but each sleeve packing costs more than a
ten-hour day of skilled labour, so it's quite a hole in the budget.
The numberplates went to the buffing shop during the week, surfaces are
prepared using rotary tools, first a wire brush, then lustre polish on a
cloth mop. The resulting high shine is very satisfactory.
A new problem emerged concerning the coupled wheel springs: the smithy
finally got round to reconditioning the four springs we removed, and found so
many broken leaves that they ran out of material of the correct thickness and
width to make replacements, with one spring still to repair. A long search of
the workshops and the running shed finally yielded three suitable long leaves
which we hope can be cut down to make the five we need. However, the four
springs still under the locomotive will very probably also have some broken
leaves, and we will have no suitable spring steel. Fingers crossed!
Tuesday 30th May 2006
Some time was spent last week inspecting the air brake pistons on the
locomotive and tender. Some minor rust should not be an obstacle to
operation, but the rubber seals are slightly damaged on one of the pistons
and it seems there are no spares. Can anyone advise whether there are modern
compounds around which can repair slight cracks in rubber seals?
We collected the various coupled axlebox components together in readiness for
assembly. Only then did we remember that one of the keeps had a broken
corner, which we had not repaired. Closer inspection showed that it was also
cracked, and so incapable of doing its job as an oil reservoir. Fortunately
the foundry had cast a spare keep for me in brass some time back, so it was
relatively easy to machine this casting as a substitute. If brass turns out
to be unsuitable in service, we will make another casting in iron.
On Saturday we prepared the axleboxes and springs on the driving and
trailing coupled axles, and on Sunday we put the driving axle back under the
loco and removed the leading axle, using the wheel drop pit. Some welding
work was necessary to repair worn rocking plates on the frame brackets for
the spring hangers. The seals on the hydraulic jack in the pit are failing,
which means it has a tendency to sink under load; in fact we had to relieve
the weight on the axle using the overhead crane before the jack would pump
the last couple of centimetres. It was a relief to find that the machining of
face and hub liners we had done, based on measurements, seems to have
resulted in the correct side play of the axleboxes in the horns. It would
have been very embarrassing if they had not fitted.
We prepared the trailing axle for replacement, and prepared the intermediate
axle for removal from the loco, but ran out of time with the wheel drop on
Sunday evening (lighting in shop 010 is very poor, and when the sun sets at
1830 it's time to find all the tools and lock them away before it's too dark
to see). I hope we will complete this work during the coming week. We also
continued to fit and erect the valve gear, including the remetalled crosshead
slipper blocks with their new brass liners. We had miscalculated the latter's
thickness, fortunately leaving them oversize, so more machining was
necessary. The air brake actuator cylinders were serviced and new
floorboards fitted in the cab, making it a much safer place to work. New
wooden packings were fitted to support the main air reservoir under the
boiler before the driving axle was replaced.
Checking the condition of the leading and intermediate wheel bearings and
side, face and hub liners is the next important task. If we are lucky there
will be little damage and they can go straight back under the locomotive; if
not we will have to renovate them, but we have now the experience from the
last few months' work to draw on. We then have to re-erect the connecting and
coupling rods, finish work on the brakes (including re-erecting and adjusting
the pull rods under the loco), and give everything a final check (and no
doubt complete many small details not quite finished). Then we can fill the
oil bunker and boiler, light up, and see if we can raise steam pressure.
Thursday 1st June 2006
On Tuesday afternoon we attempted to replace the trailing axle under the
locomotive. After several hours we were forced to admit defeat; no matter
how carefully we tried to align the axleboxes in the horns, one or other
jammed as we jacked the axle upwards in the wheel drop. Darkness made us
call a halt.
On Wednesday morning I went over the axleboxes and horn guides with a tape
measure. The most likely reason for jamming was that we had left too little
side play between the horn guides and the axlebox side slides, but the
dimensions seemed correct. Eventually I realised that one of the axleboxes
was not sitting snugly against the wheel hub liner. A quick check showed
that the face liner of the axlebox had not been machined correctly, it was
several millimetres thicker on side than the other, meaning that the
axlebox, if forced against the hub liner, was bound to jam in the slides.
The box was taken back to the machine shop and worked on for several hours
after the end of the normal shift
 |
| Reassembling axleboxes. Once bolted up, they are very top-heavy, and hand upside-down on the axle. To get them back in the horn slides underneath the loco in the restricted space of the wheel drop, two men guide while a third pumps the ram of the jack. The team swaps places every five minutes and sweats freely. Water laps around your boots. The axleboxes jammed again and again and again.. |
Thursday (today) is a public holiday, which allowed another attempt at
fitting the trailing axle with the newly-modified axlebox. This time we
succeeded, although much hammering and shaking was still necessary to
convince the axleboxes to go up the slides smoothly. The side play now looks
to be just about correct. We also dropped the intermediate (i.e. third from
the front, between driving and trailing) coupled axle and dismantled the
axleboxes. In the process we had to lift the loco from the tender end to
relieve the weight on the axle. This caused the front of the loco to dip and
the main frame smashed the oil cups mounted above the bogie wheels (there is
only about a half inch of clearance with the springs slack, which none of
us remembered). Replacement will be simple, but it was rather chastening to
make this mistake.
The state of the leading and intermediate axle bearings is not perfect, but
not as bad as the driving and trailing axles. The hub liners, though worn,
are acceptable. The face liners of the leading axleboxes are only lightly
worn and are acceptable; those of the intermediate axle are worn and loose,
and will need to be built up by brazing then machined. Three of the four
brass bearings have damaged whitemetalling (cracks rather than melts) and
will need to be re-metalled and machined. Three of the pins connecting
axleboxes to springs are broken and replacements will have to be
manufactured. The springs themselves seem to be sound. We will start on
these remedial works tomorrow, but will probably not be able to have
everything ready for the coming weekend. Fortunately, the workshops recently
had a delivery of foundry coke, so re-metalling should be less problematic
than before. Which reminds me, I must ask them to cast some more iron cores
for piston valve rings while the coke lasts!
We finished the day by moving the locomotive (using the overhead crane) so
that the tender is over the drop pit, to facilitate inspection and repair of
the triple valve and the brake rigging. Several tender spring hanger pins
are loose or broken and will need to be replaced. We will also inspect the
keeps carefully for any sign of damage to the bearings and if necessary will
drop the axles to check. Finally, we removed the bogie from the locomotive
again so that it can be painted and have the keeps filled with new worsted
material soaked in oil.
Thanks, Trevor and Ian, for your suggestions on the rubber seals for the air
brake actuating cylinders. In my ignorance I had not realised they were
standardised. If we cannot find spares in the stores tomorrow (this time we
will check for complete cylinder assemblies as well as individual seals), I
will investigate further.
Tuesday 6th June 2006
The leading and intermediate wheel brasses had their whitemetalling renewed
on Friday 2nd June. Now that there's plenty coke to heat the crucible, there
seem to be fewer blowholes evident in the result. The metalling shop (047)
has a fancy jig for remetalling bearings, so I asked if ours would be done on
it. "Oh no", they said, "that's for wagon brasses. Yours are
too large". After some further prodding, I was shown a large pile of mud
as an important part of the process. The bearings are simply placed on the
floor of the shop and the molten whitemetal poured in from a ladle, with mud
piled at each end to stop the metal flowing out, and presumably a core to
give the correct profile. Crude but effective; the result is very neat.
Due to family demands I was not able to be around much during the weekend,
but the valve gear was worked on further, the Westinghouse brake actuator
cylinders renovated, the tender triple valve removed and serviced, and the
tender wheel bearings checked for signs of having running hot (none were
discovered). Thanks to Trevor and Ian's suggestions, we consulted staff in
the wagon shop (021) and found that they could give us all the Westinghouse
cylinder rubber seals we needed. The tender right side cylinder is too badly
corroded to be easily serviced, so we aim to fit a complete new assembly;
which we think we have found in store.
The intermediate axleboxes were machined over the weekend. The same mistake
was made as before, side liners not orthogonal to face liners, rather to my
annoyance. They are now being corrected, and the axle bearings are being
machined.
Painting also commenced at the weekend. Red undercoat replaced the grey of
the originally-planned KUR graphite livery. I am sorry to see it go, since I
like the locos in graphite, but am forced to admit the EAR maroon will be
more cheerful. The bogie and loco frames were painted black, and preparations
made to paint the insides of the frames red.
On Tuesday we managed a three-hour work session after hours. The bogie had
its keeps filled with soaked worsted packing, and the horn stays fitted. The
recalcitrant taper pin securing the right hand union link in the Walschaerts
valve gear, which had refused to budge, was eventually removed after careful
heating with a gas torch. The union link was taken to shop 004 for rebushing.
A loose cab footstep was removed and readied for more secure refitting.
Friday 9th June 2006
More work sessions after 4pm allowed some further progress this week. On
Wednesday I planned to put the freshly-repainted bogie back under the loco.
Four oilboxes.were recovered from laid-aside English Electric 87 and 71 class
diesel-electric locos, serviced, and fitted to the bogie. Around 5 p.m., we
lifted the front of the loco with one overhead crane while supporting the
back of the frames with a second crane through the cab roof. The bogie was
rolled under and the pivot pin centered; the loco was then lowered until the
oil boxes almost touched the frame.
It then took over an hour to convince the spring cross-shaft to go back in
place. The next stage was to tension the underhung bogie springs, raising it
so that there would be more clearance for the oil boxes. The nuts on the
spring hangers cannot simply be tightened with a spanner against the spring's
tension, since a retaining washer above the nut has wings designed to stop
the nut turning. Instead the spring has to be jacked up to take the tension
off the nut, so the retaining washer can be lifted and the nut turned. We did
this by successively lifting, packing the springs, then lowering and
tightening the nuts.
By the time we finished it was 8 p.m, long since dark and the two overhead
crane drivers marooned in the gloomy heights of the shop showed considerable
patience. Even then, we were not able to complete tightening the springs and
had to leave the front end of the loco packed up before the cranes could
release the load.
On Thursday we completed the spring tightening and removed the packing. The
inside framing of the tender was also painted red, in spite of the pit being
full of water and the pump breaking down; the painter simply rigged up a
plank over the water and got busy with his brush.
I also realised one of the axleboxes from the leading wheels had a loose face
liner, which I had previously overlooked since the liner was not badly worn.
We replaced the worn liner screws with new ones then brazed up the surface of
the liner so it becam secure. The axlebox was then sent to have the face
liner machined back to size.
Geoff Warren made a welcome appearance back in Kenya. It is sobering to
realise he last visited a year ago, when I was just starting to dig the muck
out of the smokebox. As usual Geoff was keen to get involved and not fussy
about whichever task was available. He did a nice job cleaning the brass cab
window surrounds and getting a good shine on them, as well as helping with
the bogie spring packing escapade.
One of the team had mentioned that the workshops lab had an ultrasonic axle
tester, so we thought it would be a good idea to get 2409's axles checked
out. This was duly carried out this morning (Friday). My worst fears were
realised when a serious flaw was detected in the driving axle; we had seen
visual evidence of a damaged area but hoped, vainly, it was superficial.
Within ten minutes we had found several suitable spare axles (from the same
1950s batch as 2409's driving axle) in the stores compound, and I began to
feel happier. The wheel shop staff sounded confident when I discussed the
prospect of pressing out the old axle and installing a new one. One of the
wheel shop fitters, with twenty- eight years'service, started out in steam
days and has fitted new steam axles before. The horizontal hydraulic press
seems to be capable of taking the wheelset complete with crankpins, although
it will be some time since it has dealt with such large diameters. The staff
are also used to setting the quartering of axles since the 47 class diesel
shunters,which are rod-coupled, require it.
An afternoon in the CME's drawing office store produced the correct
dimensions for machining the axle. Although it is quite a setback, it
doesn't seem to be the insuperable obstacle I had initially feared.
Interestingly, it turns out neither 5918 nor 3020 has had its axles tested
since revival, although it is standard practice for all diesel classes and
passenger and freight stock. I understand that the lab team will give them
some attention in the coming days.
After discussion, we plan to complete 2409's revival, steam it, and run some
light tests before replacing the flawed axle. If I run out of time and have
to leave Kenya before the job is finished, it is a lot better to hand over a
working loco with an axle flaw which can be fixed with a week's effort,
rather than an unfinished project with a sound driving axle !
We finished up tonight by building up the axleboxes on the intermediate axle
ready for rewheeling tomorrow. The spring hanger nuts have been freed, and
the buckle eyes eased out by hammering, after heating to red heat with a gas
torch. The bearings are ready, and only one spring pin and one trailing
axlebox require machining. We hope therefore to make good progess this
weekend.
Sunday 11th June 2006
Progress this weekend was steady rather than dramatic. On Saturday, the
intermediate wheelset had its axleboxes and springs built up, and was then
taken to the wheeldrop and jacked (after several hours of persuasion) into
place. On Sunday, the same sequence of events was repeated for the leading
wheelset. In addition, the safety-valve was overhauled and assembled, the
whistle connected, the air brake system combination tank and triple valve
refitted below the foot framing next the driver's side of the cab, the dome
cover fitted neatly to the boiler, and the union links refitted to the
Walschaerts' valve gear. A new rope seal was fitted to the smokebox door.
The rusted tender brake cylinder was removed, although the replacement unit
had unfortunately not arrived from stores. The connecting and eccentric
rods were overhauled preparatory to fitting.
The locomotive looks a good deal more cheerful with all wheels present and
clean red undercoat paint. We tidied up all the junk which had accumulated
on the foot framing and front bufferbeam. The next stage is to fit the
coupling rods to the wheels, then the connecting and eccentric rods.
Tuesday 13th June 2006
We have continued working three hours per weekday evening in an effort to
advance the project. On Monday we successfully put the coupling, connecting
and side rods on the loco. The procedure was to move the loco so that the
left hand driving wheel's crank pin was at its closest to the ground. We then
lifted the loco slightly first at the front to adjust the leading wheel's
crank pin, then the rear to adjust the intermediate and trailing wheel crank
pins. Next we moved the coupling rods alongside the wheels, already bolted
together via the knuckle joints, and used crowbars to hang the rods on the
driving wheel crank pin. Further small adjustments to the wheel positions
were made by lifting and levering until all the bushes were progressively
slipped onto the edge of their crank pins, then we tapped the whole string of
rods fully home and screwed on the crank pin nuts. Next we placed the
connecting rod big end on the driving crank pin, and pulled the crosshead
into place before securing it to the small end of the rod with the gudgeon
pin and castellated nut. Finally the eccentric (return crank) rod was added
to the driving crankpin and pinned to the expansion link.
The whole procedure was then repeated on the right hand side of the loco.
Some small final adjustments to wheel positions were necessary to get the
rods onto the crank pins smoothly. We then shifted the loco back over the pit
using the crane; everything moved smoothly .The crank pin nuts were renewed
and so needed to be set up tightly then marked and drilled for the taper pins
which ensure they do not spin off in use.
Yesterday Geoff Warren and I spent some time cleaning old paint and grease
off the inner frames so that they could be painted red. Meanwhile the brass
"E A R" letters for the tender had arrived from the foundry, still
warm from casting, and we cleaned up the rough edges with files and an angle
grinder. The burner and atomiser were removed from the front of the firebox
and cleaned. The gap was set correctly and the assembly returned into
position and connected up. The lubrication cups and pipes for the crossheads
were then fitted. The cowcatcher was also put back in place.
It transpired that the blowdown pipe (which allows boiler sediment to be
exhausted from near the lower front of the outer firebox and blown between
the wheels) has gone missing since the weekend. It was only a steel pipe and
therefore probably accidentally tidied up as scrap. We will have to make a
new one, which is annoying.
The next stage is to move the loco back to the larger pit in shop 006, next
5918 and 3020, and replace the brake pull rods under the coupled axles. Many
small jobs of fitting and tidying up require to be done. The missing tender
brake actuator (held up by stores bureaucracy) has to be fitted and the whole
brake system checked. The sightfeed lubricator also needs to be checked, and
the tender sides needs to be marked and drilled to take the "E A R"
letters which will be rivetted in place. I hope we will complete most of
these tasks today and tomorrow evenings so that we can steam the loco over
the weekend, leaving it warm for two days to see how the joints react to
pressure. If all this goes well, we will check all the nuts, cotters, taper
and split pins again, check the oil cup trimmings and axleboxes, and
cautiously try to move up and down the workshop yard.
Saturday 17th June 2006
My hopes of moving 2409 from the erecting shop (010) to the long pit in shop
006 on Wednesday were dashed by delays in providing a shunting engine, and
electrical problems with one of the traversers. To cut a long story short,
the loco was not moved until Friday evening.
We made some progress with other tasks in the meantime. The water delivery
pipe on the left hand side, which fitted badly, was coaxed into the correct
place behind the foot framing with repeated use of a large hammer. The brake
pull rods were re-erected below the coupled wheels. A new blowdown exhaust
pipe was made and fitted. The Westinghouse pump's suction valves were fitted,
as was the tallow lubricator for its air head.
The sightfeed lubricator in the cab was dismantled, examined, filled with
water to test for leaks, then filled with oil so operation can be checked
with the loco in steam. New cab seats were fitted, and the regulator handle
was secured properly.
I finally found a local source of thick (0.25 inch) leather, sold by the
kilogramme for boot sole repairs. The upholstery shop used this to cut eight
new gaskets for the tender oilboxes. The alternative would have been to use
neoprene rubber sheet, but apart from costing twice as much I was not
convinced that the neoprene had the necessary "give" to make a good
seal on the rough castings.
An electrician started to fit the front and rear market lights. The rear
light was originally an oil lamp, later updated with an electrical fitment,
and this will be retained. The front lamp was missing when we got the loco so
a more modern (but still steam-era) lamp will be fitted instead.
The air brake actuator on the tender right hand side was finally replaced,
with some difficulty due to poor access to bolt heads. We had connected the
factory compressed air supply to the brake system and were starting to find
and fix leaks in joints when the shunting engine finally arrived and we moved
2409 to shop 006 at dusk on Friday. Everything went smoothly and no strange
noises came from the loco, more than could be said for 5918, whose cylinders
protested horribly when shunted a short distance. They must be dry as a bone.
Today (Saturday) a small team worked to fill the fuel bunker with oil and the
boiler and tender with water. The oil delivery piping is all newly-fitted so
we opened one cock at a time along the pipe route, expecting to find some
leaks. In fact only one union turned out to have a problem, but fixing it was
not simple, and a replacement union was eventually required. Fitting this
took most of the afternoon. Filling the boiler revealed some minor leaks from
the mud collector (inspection door) beneath the boiler as well as from the
blowdown valve. These will be fixed tomorrow morning, then we hope to light
up the burner using factory air pressure connected to the atomiser, and
raise steam.
We are far from finished however; I have a list of over 50 small items which
need resolved, not to mention the need for a new driving axle and any other
problems we uncover after steaming.
Sunday 18th June 2006
We started to prepare 2409 for steaming this morning. Resolving water leaks
from the boiler took longer than expected and ultimately required the removal
of the large air receiver on the running board to give spanner access to the
mud collector (inspection door) below the boiler. Shop 006 has no overhead
crane so this took some time.
We had also discovered yesterday that the bogie was riding far too low, in
fact the pivot pin of the bogie is bearing on the brake hanger cross-shaft
directly below it, instead of having two inches clearance as it should do
(and did before we dismantled it!). We spent quite a lot of time today
jacking the loco up at one end or the other using manual screw jacks and
plenty of muscle power, in order to tighten spring hangers nuts. For a while,
it seemed we had fixed the problem, when we tightened the spring nuts on the
driving, intermediate and trailing wheels. When we did the same on the
leading wheels and the bogie springs, however, it reverted to its previous
position. At the end of the process, however, we seemed to be no nearer
getting the bogie to behave properly. Some reflection is called for, since
none of us can work out what we are doing wrong. Suggestions are welcome!
Around two p.m. we connected the factory air supply to the light-up cock,
turned on the blower to create a draught and the atomiser to spray the fuel
oil from the burner into the firebox, and lit the fire by throwing in pieces
of flaming cotton waste. After a couple of hours, the boiler was warm, but no
steam pressure was shown on the gauge. We found and fixed a number of blowing
joints in the atomiser, blower and elsewhere, much easier with compressed air
than with steam, since you can feel for the exact source of the leak with
your fingers. This improved the draught from the blower, but two hours later
the pressure gauge was still obstinately at zero. We experimented with
different fuel, atomiser and blower settings, and eventually got a more
business-like fire going.
Still nothing on the gauge though; then I saw a curl of steam coming from, of
all places, the anti-vacuum valve behind the chimney. This could only mean
that (a) the regulator was not properly closed and (b) we had assembled the
anti-vacuum valve wrongly, since it is meant to open to prevent a vacuum in
the steam chest, not to vent perfectly good steam before it gets to the
cylinders!. Sure enough, the regulator was open a crack. (The tender
handbrake was on, the loco in mid-gear, the cylinder cocks open, and the
traverser in place in front of the loco, before you ask!)
Around 7 p.m., the pressure gauge was still perversely at zero. However steam
was clearly being produced. Opening the steam cock to the left side injector
resulted in a jet of steam; and when someone pulled the whistle cord, the
loco gave voice for the first time in maybe 25 years; not a watery gurgle,
but a strong sharp blast.
We were forced to conclude that the pressure gauge, which had supposedly been
tested in the lab, was faulty. I think we probably had about 50 or 60 psi
pressure when we shut the fuel supply off. The Westinghouse pump began to
thump, and steam began to issue from all the right places, as well as many of
the wrong ones!
Since it was now well after dark, and the team had been working for over
twelve hours, it was too late to do much about fixing the many small blows,
but I made a thorough survey by torchlight and listed the defects. Yet more
stuff to do! All of it looks achievable though. One disappointment was that
the firebricks in the firebox have bulged or even collapsed, even though the
loco did not move an inch. I can only assume the mason used the wrong cement,
but will try to find out more tomorrow. We are a long way from having a
reliable and useful loco to add to the Kenya steam fleet, but I feel we made
an important step forward today.
Friday 23rd June 2006
We worked on 2409 every evening this week from 4pm to 8pm, repacking pipe
joints, adjusting the burner and its control apparatus, removing (with some
difficulty) and replacing taper pins in the motion which had been incorrectly
fitted due to inexperience, and adjusting and finishing off the loco's brake
rigging. The damaged firebox brickwork was replaced; the trouble was traced
to firebricks from a substandard batch which had been mixed with good ones
when the job was first done. Some nights we had ten men working on the loco.
By 8pm last night we were all set for a steam test today. We had pressed and
refitted the regulator lever so that it fitted tightly on its spindle, and I
wanted to make sure it had been set so that the main valve was firmly closed
before the lever met its stop in the "shut" position. I gave it a
good rattling open and shut. There was a clanking in the boiler in response,
and then the lever jammed half open ! No amount of persuasion could restore
its full range of travel.
It seems probable a pin has dropped put of the control linkage to the main
valve. On the 24 class, unfortunately, this is entirely within the boiler, so
we will have to remove the steam dome forging to find out what has happened
and fix it. This is a four-man, four hour job, so we cannot steam the engine
today as planned. Planned maintenance of the mains power supply in the
workshops will also mean we have no air pressure to light up during the
weekend, so it may be Monday before we can try again. This is frustrating,
but it is better to have found a problem with controlling the main valve
before going on a line test rather than during it ....
Sunday 25th June 2006
We removed 2409's steam dome on Friday afternoon and discovered that two pins
in the main valve control linkage had not been fixed with split pins; as a
result they had simply fallen out when the regulator was operated. I did not
personally supervise the fitting of the main steam valve some months back,
but two of the senior retired steam men did, and it should have been picked
up then.
We also noticed that the pins were a loose fit, and decided to machine new
ones to replace them. This took the rest of Friday evening and we went home
late.
On Saturday, it was disappointing to find that fitting the new pins resulted
in the small and big valves binding so that they operated together, instead
of the small valve opening first. On the 24 class, simple slide valves in the
dome do the job, a small slide operating directly in sympathy with the
control rodding and the big slide following it via a slotted linkage. Now we
had a problem - we had lit up at 0630 aiming to get the pins fitted and the
dome back on while the water was warming up and still have time to raise
steam using factory air pressure before the mains electricity supply was
turned off for maintenance at 0900.
There we were sitting on top of the boiler wrestling with the tight pins in
water which was growing appreciably warm. We had no machinist on Saturday and
tried hastily and in vain to file and grind the pins so they'd let the two
valves operate smoothly. The water got warmer. Eventually, the penny dropped:
the people who fitted the loose pins knew what they were doing and had found
the best way to make the worn linkages work reliably. We put the old pins
back and satisfied ourselves that the regulator operated the valves smoothly.
All was well and we got the dome cover back on and started to bolt it down
around 0830.
With the boiler already warm, it seemed feasible to raise steam if we could
just get a little more time with factory air pressure. I set off to see the
head electrician and negotiated a one-hour extension. Back at the loco I told
the team and watched them continue bolting down the dome. I vaguely heard
someone complain about the black smoke pouring out of the chimney a few feet
from where they were working, and busied myself with something else.
Around 0945 I went back to the cab and found the fireman had swept and
cleaned the cab floor beautifully and was fiddling with a blowing steam joint
on a minor pipe. But the boiler pressure was still low and the fire seemed
timid. When I pointed out he had fifteen minutes left before the air went
off, he jumped as if shot and it turned out he'd eased back the burner in
response to the complaint about smoke. It seemed he'd lost concentration and
forgotten we had limited time. He opened up the fuel and burner cocks again
but failure was now inevitable and sure enough, the power went off on the
stroke of ten, before we had enough steam to become independent of the air
supply. My frustration is better imagined than described, since we had the
whole team there ready to work all day. Nothing for it but to go home and
take the kids swimming.
On Sunday, with electric power assured all day and the dome firmly in place,
we started to raise steam again at 0700. By 1030 we had about 60 pounds
pressure and were able to do without factory air. Our pressure gauge, in
spite of being calibrated during the week, still did not work. The trouble
was finally traced to a blocked copper pipe and remedied. Most of the steam
blows previously identified had been fixed, but the blowdown valve under the
boiler was still leaking, and as pressure rose above 100psi a gasket
partially failed and the steam and water leaks became significant.
Since we could not fix the leak until the boiler was cold, we continued to
raise steam. I wanted to ensure that the safety valves blew off at 165psi as
the top priority, and to test the Westinghouse pump and air brakes. We had
also found hat the reversing gear was very stiff indeed. Partly this was due
to interference with pipework on the right side of the loco, but even after
this was fixed it was hard to move the gear from full forward to full
reverse. We spent some time taking down the valve gear and reassembling it,
checking fits of pins and slides, but did not get the problem solved
satisfactorily. It may well be a worn scroll nut on the screw reversing
control in the cab, but we did not have time to go into it further.
Meanwhile, the sight feed lubricator had been tested an adjusted, and some
issues with pipework resolved. The generator was tested successfully,
although the electrician still has some work to do on wiring and switches
before I will be satisfied.
Another problem presented itself. We were using water and steam faster
than
normal due to the leaking blowdown valve, as well as various other
blows, and
it turned out the right side injector was inoperable, faulty cone
suspected, and the left side, though capable of lifting water, leaked
steam. We had
fitted a new steam cock but had not appreciated that new or not, it
requires
to be ground to fit the valve seating before it is properly steam tight.
We
could not build steam pressure above 120 psi; since every time we got to
that
level the losses from leaks were such that we had to turn on the
injector and
watch the pressure fall as cold water came into the boiler.
It became obvious by 1600 we would not reach 165psi, so we concentrated on
ensuring the Westinghouse was in good shape, which it seems to be. We
adjusted the brake pull rods under the loco as best we could given the amount
of steam and hot water pouring out. In spite of the pump thumping away, air
reservoir pressure stubbornly refused to rise above 20psi. Eventually we
found and fixed a blowing union in the air piping in the cab, but by now it
was 1730, the water was falling again, we had about 90psi on the gauge and
everyone was tired.
Omondi, a regular KR driver and usually the stabling fireman for 5918 and
3020, had been tending 2409's fire. He was very reluctant to risk moving 2409
without brakes (the tender hand brake functions but is an unknown quantity at
this point, and we did not have enough steam for the pump to raise working
air brake pressure). Behind us were 5918 and 3020. In front was the
traverser, with the wheel shop building on the other side without any kind of
buffer or stop-block. Still, I was damned if we had come this far without
trying to move the engine.
Omondi wound the loco into full back gear, whistled, and tugged the
regulator open. Steam gushed through the open cylinder cocks on the left
side, but not on the right side. Nothing else happened. Eventually we
realised that the piston was at the limit of forward travel on the right side
and that the lack of steam through the cocks was nothing to worry about.
Another tug on the regulator, then another. This time there was a very slight
jolt. Twice more, and 2409 rolled gently backwards under its own power for
the first time in two decades, until checked as the tender centre coupling
met that of 5918. We coupled on and wound into forward gear. 2409 responded,
but was not able to move 5918 from a dead start (and in retrospect it was not
a good idea to add momentum with 250 tons of Garratt if we had got her
moving!). Set back again, lift the chopper coupling, back into forward gear
(each reversal a big effort due to the stiff mechanism), then we moved 2409
gently forward a few feet, staying under cover of the roof in Shop 006 and
not going as far as the traverser.
So the engine can move itself forwards and backwards. I was delighted, and
the team was amused and pleased for me. We have a lot of work to do in the
coming week, fixing blows and faulty injectors, before we can steam again,
test the safety valves, and check the brakes. At that point we should be able
to get the boiler inspected and certified, move up and down the workshops
yard, and then concentrate on solving the issues of stiff reversing gear,
bogie spring settings, and pressing in a new driving axle.
Thursday 29th June 2006
Monday, Tuesday and Wednesday evenings this week were spent repairing the
defects noted on Sunday, mostly steam pipe blows, but also removing,
servicing and replacing the right side injector, resetting the burner so the
fire is evenly spread in the firebox, and repacking the cylinder stuffing
boxes on both sides. We also attached the new brass numberplates, which I
think look very nice.
Today I planned to steam the engine, but only one of the two Central
Workshops air compressors was working today. This meant that some of the air
system had to be closed down in order to ensure the wagon shop had enough
pressure for rivetting and the paint shop for spraying. In fact, we did not
get air pressure until 1430, and then the fire was badly adjusted until 1600.
As a result it was 2000 before we had enough steam to disconnect the factory
air supply from the light-up cock. After that, however, we raised steam
rapidly. A few faults are still in evidence: in particular, the left side
injector is still blowing steam badly. Otherwise, however, only minor
problems arose.
We continued to raise pressure above 120 psi, and were able to test that the
air brake operated satisfactorily. Pressure continued to rise until the red
mark on the gauge was reached at 165 psi then the needle kept going without
the safety valves lifting! It turned out the springs we have used are for a
higher boiler pressure and the holes for a securing split pin above the
safety-valve nuts are therefore in the wrong place. We will modify the bolts
tomorrow.
In the meantime, we closed the burner at 170 psi, refilled the boiler,
bringing the pressure down to about 110 psi, and then moved backwards and
forwards a few times onto the traverser, using the air brake to stop. I
couldn't resist asking to take the regulator for one of these moves. The only
previous occasion I've driven a locomotive was aged nine, at a colliery in
Scotland, with an 0-4-0T "pug", which, come to think of it, was only ten years older than 2409. We finished off at 2200.
If we are able to repair the injector and set the safety valve tomorrow, we
will steam the loco again over the weekend.
Sunday 2nd July 2006
On Friday we machined new seats for the quick-acting steam valves on the
injectors, but the valves were not reassembled in time for Saturday morning,
so it was not possible to steam the locomotive that day. Unusually, overtime
had been approved for the millwrights to work on 3020 and 5918 over the
weekend, so I had to work largely on my own on Saturday, removing pipework
with pinholes so it could be brazed. This was done late in the evening and
the pipework teased back into place ready for steaming the loco today
(Sunday).
The workshops compressor was out of action until late this morning so it was
1600 before we had steam raised. Frustratingly, we still have problems with
injector steam valves and other steam blows, but one injector works
satisfactorily, meaning that we could refill the boiler.
My intention was to set and test the safety-valves, but by good fortune
foreman millwright Fred Anyasi had convinced the boiler inspector to come
into the workshops to follow progress with 3020 (having three new tubes put
in this weekend) and 5918 (which has had its lubricators serviced and will
now have its boiler chemically descaled). The inspector was able to witness
the setting of 2409's safety valves, which were duly adjusted to lift at
165psi and 170 psi respectively. To my great delight he confirmed he would
now issue a full boiler certificate.
 |
| Certified! 2409 on No 2 traverser outside shop 006. We are all very pleased with ourselves. |
We had moved the loco out of shop 006 onto the traverser to avoid the steam
from the safety-valves dislodging soot from the smoke hoods in the shop.
Since we had a full head of steam and an hour of daylight left, I asked
fireman Omondi to take the loco to the other end of the workshop yard. The
workshops shunting engine (4721, a Hunslet- designed 0-8-0 diesel-hydraulic
built at Swindon works in 1979 by British Rail Engineering) was parked in the
way, so we coupled up to it and propelled it in front of us. This was the
first time 2409 has been on curved track since having its wheels out, and I
held my breath in case we'd got the axlebox sideplay wrong, but all was well
and the loco negotiated the points, curves and poor track of the workshops
yard quite happily.
I was keen for Omondi to carry on out of the workshops towards the running
shed, but he was unhappy about it. Eventually he explained that he'd never
passed as a driver when he was a steam fireman, and was therefore technically
not permitted to drive the loco onto the working railway. This gave me an
idea, however, and after a quick phone call I established that regular steam
driver Ben Mwoki had just booked off after driving a diesel-electric to
Nairobi from Mtito Andei. He was quickly on the scene, very keen to see how
2409 would handle. With darkness now falling, Mwoki drove the loco out
towards the running shed before returning to shop 006, still hauling the
shunting engine. 2409 performed well, although a tendency to slip easily
suggests that we have not got the springs correctly set.
I had planned to go for a line test before dropping the driving wheel set in
order to change its flawed axle, but on reflection we cannot really risk a
trip with dodgy injectors and badly set springs. Since I now have less than a
month before leaving Kenya, the aim is now to get the loco over the wheel pit
as soon as possible next week, remove the axle so that the wheel shop can
deal with it, and while that is under way, fix the injectors and other
faults. With a lot of luck we will get the loco back in working order and
have time for a line test before the end of the month.
Sunday 16th July 2006
The first week of July was a busy one for 2409. Injector steam cocks were
removed for lapping to eliminate steam blows, then replaced. The
Westinghouse pump was removed from the smokebox using the overhead crane, so
that the leaking copper gasket on the steam head could be replaced. The pump
exhaust ring in the smokebox also had to be removed, which revealed some
leaks due to poor quality welding at an earlier stage of the project. A new
repair was made by brazing.
I decided to take the bull by the horns regarding the flawed driving axle.
The side rods were lifted off, the brake pull rods dismantled, and the
driving wheels removed using the drop pit. The axle was pressed out of the
wheels in the wheel shop (005) using their Berry press with a pressure of 100
tons. A new axle (or rather, a 53-year- old spare axle from the stack in the
stores yard) was machined to the same wheel seat and journal dimensions as
the old one. First, the ends were centre-drilled to form recesses for the
lathe and grinder centres. The old axle, in spite of being flawed, had had
little journal wear, so preparing the new axle only required removal of
about ten to twenty thous from the diameters, which was achieved by
grinding.
The 24 class wheels are keyed to the axles to ensure alignment with
crankpins, so the next stage was to put the new axle on the marking table and
mark out the keyways, taking great care to ensure the 90- degree right hand
crank lead was accurate. A boring machine was used to mill out the keyways
(since the slotting machine was broken). Finally the axle ends were chamfered
on a lathe to guide them into the wheels. The axle was returned to the wheel
shop and the wheels pressed on. The first wheel went on very smoothly, but we
did not take enough care to check keyway alignment when pressing the second
wheel on and we got it a few degrees out. Fortunately this was noticed well
before the wheel was pressed fully home, and a force of only 20 tons had been
applied. The wheel was pressed off again, correctly aligned, and pressed on
fully, a process which sounds simple enough but took two hours of work to
effect, and was complicated by darkness falling and inadequate lighting. One
of the most important pieces of project equipment of late has been my torch!
 |
| Driving wheels pressed off; new axle in place on the Berry press. |
The brake pull rod on the 24 class is a two-inch steel rod centred under the
axles, with threaded portions where nuts secure the brake hanger crossbeams.
The nuts are tightened up as the brake blocks wear down with use. One of
these threaded portions had become worn out over the years and the nuts could
no longer be tightened. Since we had removed the pull rod to drop the driving
wheels, we took the opportunity to repair it. The worn area was built up by
welding, then new threads cut on a lathe.
While the wheels were out, we also corrected a mistake made earlier when we
had welded rocking washers for the driving wheel spring hangers at the wrong
angle. The washers were cut off and new ones welded in correctly.
I spent the second week of July away from Kenya, but arranged for painting
work to continue. The loco was given a second undercoat of dark red paint,
topped by two coats of EAR maroon. The numberplates and buffer beams were
painted vermilion. This weekend, black edging and yellow lining were applied
to the cab and tender.
 |
| William Buoro. A retired locomotive inspector, William was the main source of knowledge about what needed done to the loco for it to be fit for main-line service. A gentle, patient and friendly guy without whom the project would not have happened. |
I returned on Saturday morning and mechanical work recommenced.The driving
wheels were prepared (a new hub liner welded on, then axleboxes and springs
built up) and lifted back into the frames. The brake rods and side rods were
put back, and the headlamp replaced in front of the chimney. The bogie
springs were reset correctly, and a second set of new crankpin nuts and taper
pins prepared; the first set had been very hard to remove due to jammed
taper pins. We had not appreciated the importance of ensuring the taper of
the hole through the crankpin nut, the taper pin itself, and the holes for it
in the rim of the crankpin nut all matched, and as a result the old taper
pins had bent and jammed in the crankpins. Getting this right has been
time-consuming and frustrating but will pay dividends in future.
We still have to re-erect the left hand connecting and eccentric rods, but
after that will move the loco back to shop 006 for steaming, and if no
further problems emerge, will plan a line test later this week.
Wednesday 19th July 2006
We finished the few remaining tasks with the side rods on Monday morning but
missed the chance to get the shunting engine to move from shop 010 to 006. In
addition, the workshops labour force staged a sit- down strike in protest at
not being told their severance terms, only two weeks away from Rift Valley
Railways' takeover of the system. "Sit-down" is a literal term in
this case. The machine shop staff usually have their morning tea at 0900
sitting on the edge of the large traverser between shop 004 and shop 006.
This gives them the chance for a group discussion or kamukunji. The tea-time
kamukunji was therefore extended to last the whole day with most of the
workshops staff.
This was inconvenient in several ways. We could not continue with repairs
very openly since those working on 2409 would be seen by their colleagues as
lacking soldidarity, with appropriate physical consequences quite likely.
Instead I decided to raise steam in shop 010 after staff had gone home. This
being a cold time of year or Nairobi (night-time temperatures around 13-14
centigrade), the heavy fuel oil is thick as tar and flows very reluctantly.
We raised steam for six hours without getting any useful pressure in the
boiler. At ten p.m. we gave up. On Tuesday we moved the locomotive in the
morning to shop 006 but by the time we reached the large traverser, the
kamukunji had already begun. I was about to ask for co-operation to let us
use the traverser, which I'm reasonably sure would have been agreed, when
prayers started, and things inevitably grew more passionate and heated as the
orations continued. Discretion was definitely the better part of valour in
this case, not least since we would have been blowing thick smoke at the
kamukunji for the rest of the day. We retreated to the other end of shop 006
and raised steam inconspicuously. The fact that we were blocking an access
line did not matter, since no production was taking place in any case.
We started to raise steam around ten a.m. Even though the boiler was still
warm, it was growing dark before we had full working pressure. Then two minor
defects arose, which nonetheless were disastrous for my plans to go on a
test run. The whistle, which had had a steam valve and had been
over-tightened, turned out to have sheared its threads an literally blew off
the boiler when operated. Fortunately it didn't hit anyone when it came back
to earth. In addition, we could not make the generator work. Ben the driver
shook his head; he was willing at a pinch to run on the main line with no
whistle, but not without a headlight. So we simply ran down to the running
shed and back a couple of times, then returned to the workshops to try again
the next day.
Several other small defects had to be rectified, notably a cracked air pipe
near the triple valve which meant only the tender brakes were effective. It
was midday before we could start to raise steam again. The sit-down had ended
(a circular from the managing director instructing staff to resume work and
wait until August 1st to learn their fates, or leave now and forfeit all
benefits) so work could continue openly.
Raising steam was again a long slow
process, but by six p.m. we were ready. The generator agreed to work this
time, so we had lights. The oil was still thick and the fire hard to manage,
and the fireman was nervous of running far, so we ran up and down the yard to
the West Junction and came home again. The loco performed smoothly, with a
good ride and no blows at all from the cylinders or valves. We had to creep
around carefully; the yard and loco shed are busy places these days and
several other locomotives were also in motion. Very impressive quantities of
black smoke were produced (impressive, that is, unless you are a housewife in
the adjacent Land Mawe area) as the fireman got to grips with the firing
valve. We stabled the loco overnight so that we do not have to raise steam
again.
Today (Thursday) 3020 is to be put in steam for a line test prior to
Saturday's Naivasha excursion. She will be lit up using steam from 2409
instead of air pressure, which should speed things up. We hope to test both
locomotives in daylight, and may try to run in tandem if two drivers are
available.
The firing technique for 2409 seems to be slightly different from 5918 and
3020, and not because they are Giesl-ejector-fitted and 2409 is not. There is
a tendency for the thick oil to block the burner lip before being ejected by
the atomiser steam, resulting in a very small fire. The fireman, Omondi, has
learned to overcome this using an occasional pulse of steam down the oil pipe
from the blowback valve. This blows the clot of oil into the firebox with a
loud "pop" and a burst of flame. Before the clot is blown out, the
firing control valve has little effect, which was the reason for Omondi's
nervousness; he was only able to control the fire using the main supply cock
on the tender with a spanner. It could be that we have the burner gap set to
be too narrow, or that we are using oil far thicker than was intended by
Alco, who supplied the equipment to convert most EAR locomotives to burn oil
in 1948. Perhaps both factors play a part. No doubt more experience will
help.
As Trevor suggested in a posting a couple of days back, I am hoping 2409
might also make an appearance on Saturday for the Naivasha excursion, but
there are many issues to resolve before that can be said with any certainty.
Still, uncertainty is what makes East Arica interesting!
Thursday 20th July 2006
Today we took 2409 on a short line test to Kibera, the next station out of
Nairobi travelling west. The loco performed strongly (travelling as light
engine), although we had to pause twice to blow back the oil. The trip took
half an hour. Unfortunately we were then held at Kibera since the following
train's loco developed a fault. As a result we did not get back to Nairobi
West Junction until 1500, by which time it was too late for a proposed
double-headed line test. Several trains were backed up, awaiting a clear
line.
At Kibera, our air pump had also failed due to lack of lubrication. After a
brief but futile struggle with the pump's reversing rod, and with a waiting
down freight hooting for the road alongside us, Ben Mwoki told us to get in
the cab and cautiously descended the 1.5% gradient back to Nairobi using the
reverser as a brake. We did not want to be caught at Kibera for hours without
water, and the tender was already one-third empty. I had called Control and
warned them we needed priority, so we had been given the Line Clear, but that
was before we knew the pump was acting up!
 |
| 2409's first line test - at Kibera, before we discovered the brake pump had failed. |
 |
| 2409 and 3020, both in steam, when we came back from our line test to Kibera. 3020 was being tested prior to a charter excursion a couple of days later. |
Because of the air pump fault, and one or two others issues, we will not now
try to double-head the Naivasha excursion on Saturday. There is not time to
make and test the necessary repairs, and 3020 also requires preparation time.
Wednesday 2nd August 2006
On Monday 24 July we started on a number of repairs to 2409. The
safety-valve casing had a crack in the lip, which was brazed up. The air pump
was fitted with a local oil reservoir or "ball valve" for
lubrication, replacing the pipe from the sight-feed lubricator. New brake
blocks from the foundry were collected, machined, and fitted to the tender.
Various pinholes and blows in piping were remedied, including a sizeable hole
rubbed in the burner (atomiser) pipe where it contacted the main frame under
the cab. This hole was likely the reason for the slow raising of steam
experienced to date; half the atomiser pressure was simply never reaching the
burner.
The burner itself was adjusted to have a gap of 15 thous, and the burner
control valve altered to give more positive open and closed positions. After
the Kibera trip, the valve stops had become loose, leaving the fireman a
difficult job to close the oil supply positively. As a result we had more
than once inadvertently dumped oil into a cool firebox with the burner air
off, resulting in huge clouds of black smoke drifting across Nairobi yard
towards the station, HQ building, and central business district of the town;
not the best way to make friends!
During Sunday we had added the brass "E A R" lettering to the
tender, drilling holes for brass rivets which were cold-hammered into place
by a man inside with two of us outside holding a metal block as an anvil. The
rivets were caulked inside afterwards using bituminous sealant intended for
roofing. Unsure whether the rivets would leak with the flexing of the tender
side during a journey, we lettered the left side of the tender only, until
the line test showed if the method worked.
The repairs were completed by Tuesday night and on Wednesday we steamed the
engine again, hoping to make a test run. Brazing the safety-valve had
affected the valve seating however, and the front valve no longer closed
properly, blowing copious amounts of steam at well below the boiler's working
pressure. There was nothing for it but to shut down and try again on Thursday
after repairs.
In spite of an early start, removing the safety valve before re- brazing the
casing and removing the excess metal, then lapping the valve with grinding
paste, took until early afternoon. The boiler was still warm, but steam was
not raised until late afternoon, and the rear headlight once again decided
not to work (the fault was later traced to the switch, rather than the wiring
or headlight itself). We had tried to reset the safety valves nuts accurately
to their previous position, but when we raised pressure, we found they were
still not blowing off at 173 psi, well over the 165psi working pressure. We
quickly slapped the injector on to bring the pressure down. To adjust the
valve springs, the loco would have to cool down. Grinding my teeth, I
postponed the test run by one more day. I didn't want to give up without
moving the engine a short way, so we ran to the triangle next the running
shed and turned the locomotive so that the smokebox faced Mombasa. I wanted
to blow down the boiler, but the blowdown valve was jammed and would not open
smoothly. Ben argued against hammering to open it in case it wouldn't close
again, in which case the entire contents of the boiler would be ejected in a
few minutes, probably damaging the firebox crown. This seemed sensible
advice. We left the blowdown for another day and returned to the workshops
Before shutting down the loco, we backed onto the water bogie and first class
coach and carried out a brake test, which went smoothly. Omondi the fireman
shut down the fire, put the injector on to fill the boiler, and went home. I
stayed behind and, once the injector had knocked off as the pressure fell,
blew back the remaining steam into the oil bunker for about an hour to mix
and warm the oil ready for the following day.
On Friday morning Ben Mwoki the driver and Omondi came in at 6 a.m. instead
of the usual 8 o'clock start, knowing that I had little time left in Nairobi
and that Friday was liable to be the last chance for a decent test. The
weather was miserable, grey cloudy sky, overnight temperature about twelve
Celsius, and drizzling rain starting and stopping through the day. The boiler
was warm, however, and by ten- thirty a.m. we had raised steam. 2409 had to
wait a little while until two Class 87 diesel-electrics moved out of the way,
then backed down onto the rake of water tank bogie and first class bogie,
coupled up, and headed for the workshop gate
I had called the regional controller and asked him for a load for Thika,
forty kilometres from Nairobi up the Nanyuki branch line. The Thika line has
two commuter trains in the early morning, then two daily freights if traffic
warrants them, at nine and eleven a.m. The controller told me he had enough
traffic and would set up the load at the Up yard, at the west end of the
station. The fitters clambered aboard the first class bogie, and we set off
out of the workshops. We were joined by a cheerful guy named Joe, a U.S.
citizen working at the airport maintaining commercial jets. Joe had been on
the previous Saturday's trip with 3020 and was keen to see how 2409 would get
on.
Ben pulled up clear of the workshop gate and we went to look for sand at the
drying shed. There was hardly any left, the shed had been swept clean by
diesel drivers facing the climb to Kibera on greasy, wet rails in the
drizzle. We filled two cans of sand with difficulty and brought them to the
cab. Ben started to propel the rake westwards through a crossover. 2409
slipped madly most of the way, although the track was level and the load only
about 95 tons at this stage. Eventually Ben cleared the neck of the shed
access lines, then drew forwards on the exit line from the shed towards
Nairobi East yard ground frame, stopping at the warning board. We sat there
for half an hour while two 62 class shunters pulled wagons to and fro in
front of us. Both Ben and I departed in an attempt to find out what was
happening. No-one seemed to know what to do with us.
Two Dutch enthusiasts had turned up to visit the running shed, hoping no
doubt to catch an 87 diesel-electric in from that morning's Kisumu
passenger. Walking from the station, they rounded the rakes of sorted wagons
and were suddenly confronted by the sight of 2409 hissing away on the exit
road. You could almost literally see their jaws drop before they got busy
with their cameras. For good measure, an 87 pulled up behind our rake. They
only had half an hour before leaving to catch their flight and they used it
well.
Eventually Ben got hold of the running shift foreman at the shed, who
made a
few phone calls. The 62s paused sorting their wagons and let us through
so we
could propel our rake to the Up yard and find our load. Again, wheelslip
was
a problem. Ben's buddies outside the yardmaster's office were smirking,
and
eventually he lost his cool. "Who set the main valve on this
engine?", he roared. I was forced to admit that I had supervised setting
the regulator inside the steam dome so that the small valve opened
before the
big valve, although in fact William Buoro, the experienced retired
fitter,
had also been on top of the boiler watching. Ben had pinpointed the
problem:
whenever he opened the regulator, the small valve was pulling the big
valve
with it, allowing too much steam into the cylinders and thus too much
torque
to the coupled wheels, which slipped instead of gripping the rails. We
had
been at pains to adjust the valve spring so this did not happen, but
clearly
the valves behaved differently when full boiler pressure was being
applied to them, something only experience could have solved. I told Ben
this. He
grunted, still unhappy, but in fact from that point on the loco stopped
slipping when he was in charge. He modified his driving technique to use
smaller dabs on the regulator handle and was able to control the loco
without
problems. I later watched several other drivers learning how 2409
handled:
some of them never quite got it right, but others were able to avoid
slipping
more or less from the word go. If we had had more time, we could have
reset
the valve, but it would have needed an extra day to take off the dome,
adjust
the spring, and put the dome back in place, and there was no guarantee
we'd
get it right the first time.
The shunter indicated our load: three covered goods bogies loaded with green
wattle bark from Eldoret for the Kenya Tanning Company. Wattle bark was one
of the earliest products grown by settlers in Kenya and it seemed fitting
that, over ninety years after the Thika branch opened, we should be carrying
such a traditional cargo. Ben shunted the train so that the CGBs were between
the water bogie and the staff coach. Our train number was K3B: the load was
ten units, 203 tons in total. Guard Osodo performed a brake test as a light
drizzle was falling, then at 1328, Ben whistled and opened the regulator.
2409 headed eastwards through the yard parallel to Nairobi station, over a
series of crossovers until the main running line was reached beyond the
station east ground frame. We passed the east yard frame opposite the loco
shed with steam shut off due to the slight falling grade, and rounded the
curve towards Nairobi East Junction signalbox, with the old boiler park to
our right still with two or three Garratt boilers rusting in the grass. We
passed the gantry of lower-quadrant sempahore signals, collected the wicker
hoop with the single-line Tyer's token from the signalman, and coasted down
towards Makadara at about ten m.p.h, passing the many sidings of the
industrial area on our right. The small ends of the connecting rods clanked
rhythmically. The drizzle had cleared up.
Past Makadara we took the branch line, curving off to the left below the
Jogoo Road bridge. Ben rounded the curve cautiously, carried on below the
Outer Ring Road bridge, then opened the regulator as we neared Dandora
station. 2409 responded with a crisp beat. All seemed to be going well, and
we had plenty of steam. Ben looked like he was beginning to enjoy himself.
The Thika branch was built as an agricultural feeder line to create traffic
for the Uganda Railway. The UR had been funded by the British government at a
time when competition with the German and French empires for control of the
headwaters of the Nile had loomed large in British foreign policy. By the
time Lake Victoria was reached, three times over budget and several years
behind schedule, Imperial priorities had changed, and the railway's
strategic importance had vanished. The railway was handed over to the local
colonial administration with a large debt to the Treasury to service, and no
established source of traffic. From early times, therefore, the Governor was
preoccupied with developing agriculture and other businesses along the
railway. The Thika branch was conceived with this in mind, but the colonial
office, still smarting from the cost of the Uganda Railway, rejected the
Governor's proposal for the branch line outright. Only by reducing the cost
to the bare minimum, and cunningly relabelling the proposal as a Tramway (at
a time when tramways were rapidly extending into the suburbs of British
cities), was funding for the branch approved.
The upshot was that the Thika branch was constructed very cheaply, with
alignments which plunged down slopes to cross rivers with the smallest
possible bridge span before climbing up the other side of the valley, rather
than using expensive embankments and long steel spans to reduce gradients.
Although the worst of the grades have been smoothed out in the intervening
years, the line still swings wildly around, seeking to minimise earthworks.
This constant rising and falling to cross small rivers makes the Thika branch
exciting to travel on in a steam loco. Often it is not possible to build up
much speed on the downward part, as there is invariably a curve near the
bottom which has to be taken carefully. 2409 didn't hesitate, however,
climbing purposefully out of the dips past Githurai Halt and then on the long
climb to Kahawa, slowing to a walking pace but then settling into a
purposeful rhythm as Ben put the engine into full forward gear and the blast
leapt high into the sky.
We stopped for ten minutes at Kahawa, where we got a new token for the
section to Ruiru. A crowd of onlookers gathered, then we were off. Ruiru was
quickly reached, and after another short stop, we left for the final section
to Thika
Just before Kalimoni station, there is an awkward gradient. The line drops to
a river bridge, veering sharply left just beyond it, and then rises at
something between 1.5% and 2% (1 in 75 and 1 in 50) before veering right and
over the crest of the rise to Kalimoni. Ben eased the train down the hill,
over the bridge and around the curve, and opened up, but I could tell from
the start that we were not accelerating fast enough, and sure enough, we
ground to a halt about two-thirds of the way up the rise. Omondi blew up
steam and Ben tried to restart on the slope, but 2409 was having none of it,
slipping madly. He backed the train up the hill on the other side and tried
again, but with the same result, stalling half way up
I had dropped off the footplate to watch from the lineside nearer the top of
the hill. After sitting for ten minutes or so, and trying another standing
start, Ben reversed his train over the bridge again, but this time kept going
back until he was right at the top of the hill on the other side. Then he
whistled and kept the regulator open on the way down.
2409 belted down the hill, over the bridge, snapped round the corner, and Ben
wound into full gear and opened the regulator wide. Black smoke shot
heavenwards. No risk of stalling this time; the train roared past me and
round the corner out of sight. I followed slowly along the ballast. The train
was waiting for me at the level crossing just before Kalimoni station. As I
came level with the staff coach, Joe the American looked out at me.
"You're not going to get that grin off your face for a week", he
commented. I had to admit he was right.
After that, it seemed an easy run for the final hour or so to Thika. The
countryside becomes more open with fewer settlements and fields, and more
long, sun-bleached grass. At one point a Range Rover with a family inside
bumping slowly along a murram track paralleling the railway stopped in
disbelief, kids hanging out of the windows, at the sight of the maroon engine
with its short goods train puffing through the bush. We waved, and they waved
back, perhaps relieved to find they were not hallucinating.
Suddenly a new noise was apparent, a groaning squeak on the right hand side.
Ben was of the opinion it wasn't the cylinders, and wanted to press on. Since
we were on a rising grade and not doing much more than walking pace, I
dropped down to the ballast (easy to do on 2409, with its low footplate: much
harder on newer locos like 3020) and ran alongside the engine until I was
certain the noise was coming from the valve chest. We stopped. The cause
turned out to be a blowing union in the piping from the sightfeed lubricator.
I knew about this blow; previous attempts to repack and close up the union
had made it blow even more, and for fear of stripping the thread on the
nipple we had simply left it slack at a "sweet spot" where the blow
was insignificant. Now it was blowing the steam and lubricating oil out into
the atmosphere rather than into the piston valve. Omondi put on the right
hand injector, and the gasket on the clack box on top of the boiler chose
that moment to start leaking, showering me with warm water. We tightened up
the lubrication pipe union, fearing the worst, but to my great relief the
blow stopped completely. The motion from the journey and the heat must have
coaxed the nipple to fit the nut better. We set off again, and the squeaking
stopped.
Twisting and turning through the scrub, the years seemed to roll away, and it
took the sight of the Thika colour-light home signal, and the level crossing
busy with modern traffic, to jerk us back to the twenty-first century. We
reached Thika at 1746.
The shunting engine driver at Thika has steam experience and had shunted 3020
for us on a previous trip, subsequently being called on to drive during the
RTC safari in 2005. He was delighted to see 2409, since he had driven 24s
when based in Mombasa thirty years before. Ben happily handed over the loco
to him to shunt the rake and turn on the triangle. I was impressed to note
that, under his control, the loco did not slip once.
We had only used half a tenderful of water, but we topped up from the water
bogie and cleaned the fire, which was getting choked with carbon deposits in
the ashpan, before restarting at 1931, well after dark. Our load was now only
about 90 tons and Ben wanted to get home. With increasing confidence he
opened up on the grades. The headlight threw a small bright circle onto the
track ahead, enough to see the rails curving sharply from side to side into
the darkness. Seated high above the fireman on the left-hand tender toolbox,
I could see ahead through the cab window as well as watch Ben adjusting the
regulator and cut-off on the right side of the loco. There is little space on
a 24 class footplate, and the boiler backhead is old- fashioned, tall and
with few controls. The experience was remarkable; suddenly the early years of the Uganda Railway seemed very near.
Omondi called something over to Ben, and we drew up. "The firing
control's broken", he told me. "Maybe there's a pin come out."
Sure enough, when I got down to the trackbed to have a look, the pin holding
the control rod to the control valve operating crank had fallen out after
shearing its split pin. Fortunately it was still lying on the foot-framing. I
found a new split pin and reassembled the linkage by torchlight, and we set
off again. The fitters in the staff coach behind us did not stir.
We reached Ruiru at 2042, just in time to see the 25-coach commuter train
empties leaving in front of us for Nairobi. (This is the longest passenger
train currently running in Kenya; longer than the Nairobi-Mombasa trains).
This meant a half-hour wait for the section to be cleared. Eventually we got
line clear and set off again, reaching Kahawa a mere eighteen minutes later.
After being held for ten minutes we received line clear to Makadara and took
off into the darkness.
I remembered my last trip over this stretch, with 3020 steaming very
indifferently. There is a long rising grade before Dandora, and 3020 had
slogged up it at less than walking pace just before dusk, with large numbers
of homebound passers-by looking curiously, and ultimately sniggering at us as
the driver and fireman fought to keep the train moving. 3020 ultimately
stalled not far from Dandora due to lack of steam. Tonight, however, 2409,
with the same load, pounded up the Dandora bank at 25 mph, whistled for the
level crossing, and coasted through the station before opening up again as we
headed for Makadara. I think that was the single most satisfying moment for
me on the trip, vindicating the care we had taken descaling the boiler and
fitting the valve and piston rings tightly. It certainly spoke volumes for
the simple and effective design of the loco. I knew Ben was thinking the same
thing, for he had been the driver that day on 3020. We exchanged satisfied
looks.
At Makadara, the outer home signal was defective, which we had not been
warned about. After waiting fifteen minutes at the signal, and with clear
sight of the line ahead, Ben moved at walking speed into the station and
received line clear for Nairobi. We reached the East Junction at 2241.
Subtracting the signal check and the time waiting for line clears, we had
done the trip in a creditable two hours ten minutes.
Our route back to the workshops was blocked by shunting operations, so we
were held at the East yard ground frame for a while. One by one the fitters
slipped off into the darkness. It was well after midnight before we had the
loco back in shop 006. Omondi put the injectors on and left the loco to its
own devices. Tired but pleased with ourselves, we left the workshops for
home.
On Saturday 29th we had a rest day. Sunday 30th was the day fixed for my
farewell party, at the Afrosa Classique bar in the run-down Land Mawe area
near the workshops. Warare, Maina the welder and I spent the morning
rivetting the brass EAR letters onto the right-hand side of the tender; our
technique seemed good enough to have survived the Thika trip without
springing leaks. The celebrations were attended by about fifty staff from the
workshops; it was surprising how many people had been involved when I
started to draw up a list. The atmosphere was more muted than at previous
parties. The men were still uncertain of their futures, since Rift Valley
Railways had been unable to finish their financing arrangements in time and
had asked for, and been granted, a three-month delay in their commencement
date, which ordinarily would have been on August 1st. Former EAR driver
Charan Singh Kundi had very generously sent me a contribution to the costs,
and a goodly amount of alcohol as well as thirty kilos of goat and beef were
consumed.
As the party wore on, we hatched a plan to have one more trip with 2409
before I left, on Tuesday 1st. Taking account of previous experience we put
the loco in steam on Monday evening and stabled it overnight, to be ready on
Tuesday. There were a number of repairs to be done, water and fuel oil to be
taken on; all in all it was close to 1300 before we were ready to move. Ben
Mwoki had been sent away to Nakuru on duty, so our driver was the regular
3020 fireman James Mathuva, also a senior driver. We collected our water
tanker and staff coach and moved off to the yard. I had talked with the
regional controller that morning and been promised a load to Uplands, on the
line to Uganda. Our train number was to be B4A. I felt confident enough to
ask a few friends to come: Roger Tanner and Rowena Buxton of East African
Steam Safaris, and Bryan Harris, chairman of the Friends of Nairobi Railway
Museum. The sun was shining and everyone was in a good mood.
Mathuva had no problem in moving 2409 without undue slipping. We were facing
the right way for Uplands, so we propelled the rake out of the workshops and
did not go to the triangle. There was still no sand at the loco shed. Mathuva
waited until the crossover points had been reversed and moved forward towards
the West junction. The line curves slightly to the right at this point before
a number of sidings from the running shed trail in from the right side.
As we passed the first of these sidings, a bystander started to wave and
point at the front of the loco. A second later we felt a heavy thump on the
footplate. Mathuva took a couple of seconds to react, then applied the
Westinghouse brake while I jumped down to the trackbed. At first everything
seemed fine, then as I walked to the front of the loco, I saw that the front
bogie wheels were off the track.
Someone went to fetch the breakdown gang, while I glumly called the regional
controller and told him we would not be able to take the train to Uplands. A
cotter pin from the bogie spring cross beam was also missing, and I could not
find it despite searching the track back to the workshops. However, the beam
had not moved significantly and I concluded it had no bearing on the
derailment.
As we waited, Mathuva took a close look at the brake blocks on the loco, and
realised that only two of the eight brake blocks were doing any useful work.
Although we had set the rigging correctly before the Thika trip, it had
clearly "worked in" and required to be tightened up. Since the
brakes were hard on against the wheel tyres in the workshops, we had not
realised this. Again lack of running experience was slowing us down.
The breakdown gang arrived and had jacked the bogie back on the track
within about half an hour. I asked Mathuva to drive slowly up to the West
junction, which he did, as I walked alongside. Onlookers must have thought I
was affected by the sun, since I was running ahead of the loco, lying down in
the track, walking alongside a few inches from the bogie wheels, and so on,
all to try and get some inkling of why the bogie had come off. It seemed to
be riding fine, whether on straight or curved track, or on pointwork. We
reversed back to the loco shed. I had a close look at the point where I
thought the bogie had come off as the rake came over it. The rail joints are
staggered, as is normal practice in Kenya, and one joint on the outside of
the curve was pumping up and down by a good two inches as the bogies passed
over.
I stopped Mathuva and asked him to drive forwards again over this joint at
dead slow speed. He obliged as I watched the bogie from track level in front
of the engine. Sure enough, as it came to the joint, the bogie dipped, then
suddenly the front wheels sprung sideways about six inches and derailed
again. I remembered that 3020 had, in fact, derailed at exactly the same spot
some eighteen months before, on its way to work a Naivasha excursion one
Saturday morning.
The breakdown gang boss was a little incredulous when I told him we'd come
off again at the same spot, although another small injection of
"gasoline" (as the railwaymen call a tip) ensured they came out
promptly enough. I had to leave the proceedings at this point, but I gather
they got the front wheels of the bogie back on, only for the back wheels to
come off as soon as the loco moved. It was 8 p.m. before they were safely
back in the workshops.
It may seem strange to have deliberately brought the loco over suspect track
in this way, but perhaps I am influenced by early exposure to software
engineering and the need to identify the conditions which make faults
repeatable! Anyway, I was pleased to have proved in my own mind at least that
poor track was the reason for the derailment. The other possible causes,
inaccurate vertical spring or side control spring setting, had to be
eliminated before I was sure the loco was safe.
While I am not certain we have the vertical springs on the bogie set
correctly, we have done our best without access to a weighbridge. (The loco
weighbridge has not worked for years, and the wagon weighbridge in the
workshops is reached via some very dodgy track, over which the shunters
refused to allow us). Instead we used the split pin holes in the spring
hanger bolts, as well as comparison with 2401 in the Museum, to set the
spring tensioning nuts. As for the bogie side control spring (which is what
caused the wheels to leap six inches instead of gently climbing over the
rails) we set the tension according to instructions on the original works
drawing, using an original spring removed from loco 2401. If anyone has any
observations about this subject I would be very interested.
So my final view of 2409 was rather a sorry one, with the loco all dressed up
with nowhere to go and the front wheels on the ballast. I left Kenya the
following day to join my family in Switzerland. Fortunately I have the memory
of the Thika trip to compensate, and some video.
If I'd had another week or two, I'm sure we would have got 2409 to Nanyuki.
Friday 25th August 2006
2409 has had a new left hand injector steam valve fitted. The brake governor
and the driver's brake valve have been serviced, and the brake pull rods on
the loco adjusted to take up wear. The replica worksplates have not yet been
fitted to the front sandboxes.
I am very pleased to hear that a German film company has expressed interest
in using 2409 for a filming contract in October, as well as 3020. I had
feared that 2409 would end up unwanted and unloved at the back of the
workshops, where its copper piping would disappear in a matter of days. Let's
hope not! A quote has been submitted to the film company and a response is
awaited. 2409 may make a test run to Sagana on the Nanyuki branch next
Thursday (31 August). 3020 is also to be tested I believe.
Epilogue: I believe the film contract was carried out, I think for a German made-for-TV series, but I never saw the resulting footage. The film company wanted the loco in Uganda Railways grey, so Kenya Railways, eager for their fee, simply painted over my lovingly-applied maroon with plain grey paint, assuring the museum staff the red paint would be restored afterwards (and doubtless charging the film company accordingly). When I visited several years later, the loco was still in grey, and had not worked again, although it was still intact. I believe it was steamed once more for a steam tourism event but did not haul a train. Finally in 2017 came the news that the railway had got fed up paying for security guard costs and had moved the loco out of a secure area ... all the copper and brass piping disappeared in a few days. "TIA", as the old Kenya hands say. At least I had some fun! |
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