D6515 / 33012 - Restoration

Work completed on 33012 during Summer 2008 is detailed below

As threatened in the previous report, we did manage to finally finish refurbishing No.1 Cab. James replaced the rotten hardboard with oil- tempered hardboard and replaced the missing aluminium trim. Dave Gravell has completely re-painted the interior to a very high standard.

But we did not work flat out on the cab! We also changed the fuel injectors. We had a set of 8 sat on the shelf for years, still sealed in original packaging from 1992. These went off to Poole Diesel for checking. They were all gummed up where the original storage oil had gone off, and the main spring settings had settled some way off where they should have been. After cleaning and re-setting they came back and we changed all 8. There is now much less smoke on start up and cold, and the engine runs even smoother. Next are the fuel pumps, there is a set of 8 ready for fitting…

Not much other progress with 33012 apart from a B3 exam. We are spending time getting ready for 33012s time in Eastleigh Works next year. Dave Axton and James decided to use 33034s generator for 12. Then we can keep the ex 33012 as a good spare in decent storage. We had budgeted for a light overhaul of the generator, and our contractors; Knowlton & Newman in Southampton were happy to take 34s generator this autumn. So Dave Gravell, Dan Bennett & James Cox have disconnected the generator from 33034. All electrical connections, crankshaft coupling bolts and all side and top fixing bolts. The armature is left supported by one coupling bolt and the internal flanges. A section of inlet manifold has to be removed, as does a part of the exhaust system, 34 lost its turbo years ago. The final preparation was completed when the roof catches were all undone. The next stage is to arrange transport and the railway’s crane.

Work completed on 33012 during Spring 2008 is detailed below

33012 returned to ‘Crompton Acres’ at Norden during January 2008 for some winter maintenance work.
There had been evidence of top liner seals slightly leaking on 3 cylinders. In attempt to stop this, we re-tightened the head nuts back to the required torque. In order to access the head nuts on a Sulzer engine, a number of components have to be removed. Rocker cover, top coolant pipe, disconnect valve rockers from pushrods, disconnect rocker oil pipes, disconnect injector spill pipes, remove rockers. With all that lot out of the way, we slackened and then re-tightened each of the 64 head nuts back to the required 750 ft/lb. Using a 5x torque multiplier and torque wrench set to 150 ft/lb. Making sure that the correct sequence was used between studs. After tightening all the nuts, the rockers and pipe work were reassembled and the tappet clearance adjusted to 0.015” inlet and 0.025” exhaust.
The engine was run up with rocker covers off, to check for oil and fuel leaks, and to double check the tappet clearance. When everything was OK, the rocker covers were replaced. The engine appeared to run much smoother after the tappets were adjusted, which probably needed doing anyway!

Last summer, we cleaned inside the traction motors. This time it was the turn of the main and auxiliary generators. These have a much cleaner environment to live in than the traction motors, so we did not remove brush boxes. All that was necessary was loosening the fine dust with a dry brush while vacuuming. Then all insulators were wiped over with electrical cleaner. Upon rotating the main generator brush ring, it was pleasing to find that the brushes were free in the bottom brush box. Often these are stuck with oil and grease contamination.
Close inspection of the auxiliary generator found that some of the insulation on its internal cables was degraded and falling apart. Sections were disconnected from brush boxes and two layers of heat shrink tubing applied to replace the missing original insulation.

At the end of January 33012 returned to duties based at Swanage.

Ever since 33012 arrived at the Swanage Railway on 1999, we have been very gradually refurbishing the interior of the cabs. Which includes; replacement of mushy hardboard side panels with new oil-tempered hardboard, fitting of new aluminium trim where it had been missing for years. Preparation and repainting. The no.2 cab was started about 6 years ago. Since then we have overhauled the engine, completely overhauled the bodywork, reinstated ETH, cleaned traction motors, in fact; anything to avoid the cabs.
So it was about time we at least finished no. 2 cab! After completing no.2 cab, attention turned to no.1 cab. At least this did not have so many bits of aluminium trim missing… Still work in progress this summer.

Prior to the Swanage Railway Diesel Gala, we washed and polished the loco exterior, and steam cleaned the bogies. In order to improve its appearance among the visiting locomotives.


Work completed on 33012 during 2007 is detailed below

Feed Cut-off Valves

These valves protect main reservoir pressure from being lost via the train pipe, when an AWS or DSD brake application occurs. Full main res. pressure in the AWS and DSD systems opens a port, to allow main res. Air to be supplied to drivers FV3 brake valve. If AWS or DSD pressure is lost, the porting inside a FCV shuts off the main res. supply to the brake valve. Like all Davies & Metcalfe brake valves, the spindle seals can become worn and hardened. When this happens in a Feed Cut-off Valve, main res. can be lost by passing through the FCV and venting to atmosphere via the DSD.

Fortunately, the rubber seals for most D & M valves are still available – at a price. The valves on 33s are stripped and cleaned at every B exam, so we fully stripped down 4 spare FCVs , removed all of the old seals and fitted new ones. The valves were changed at the B1 exam. 33012 now maintains main res. pressure overnight, somewhat of an achievement for a first generation locomotives.

Traction Motor Cleaning

This was a major project, to remove the build up of carbon dust and grease from the commutator, V-ring, brush boxes, brush ring and cables of each of the 4 motors. This was done over a 3 week period during July/ August. It needed two dedicated people on each occasion, and it was only possible to do one motor per day.

The procedure was; get loco over pit. Remove bottom and side access panels. Disconnect fixed cables from brush boxes. Slacken clamp bolts, remove locking dowel, disconnect brush ring cables from bottom brush box. Remove bottom brush box. Rotate brush ring to access next brush box. Each brush box was first cleaned in the parts washer, then with electrical cleaner. Particular attention paid to insulators. When all of the brush boxes were out, spray all accessible internal places with electrical cleaner. Hand scrub commutator, V-ring and commutator riser. Clean ends of field coils. Wipe over all cables, spray with cleaner again to remove debris. Repeat this process. Reassemble brush boxes into motor, ensuring correct gap.

It was well worth carrying out this task, because one brush box had a broken spring, which was changed. More serious was a cable that was shorting to the motor frame. The insulation had chafed away, and the conductor was gradually wearing and arcing too.

Although there are 4 cables to and from each traction motor, only one carries a positive current, the other three are negative. A short circuit to frame from any negative cable will not trip Earth fault Relay, like this cable. As luck would have it, the defective cable was the only one of the three that had a fitting on each end, the motor end of it, bolting to a brush box. The other 3 are all soldered onto field coils!

A good cable was removed from one of our spare traction motors, and fitted this to 33012. A really filthy, dirty, tiring job.

Above : The chafed cable, no.3 Traction Motor

Engine room Gutters

A feature of BRCW locos are their internal rainwater gutters. Behind the curved cantrail mesh grilles are aluminium louvred panels, which drain into the infamous gutters. This allows a pleasing external appearance, but does mean that rainwater is directed into the engine room. It is essential that the internal gutters are leak free, to avoid a rain causing corrosion to the lower body sides and under floor trunking.

A local steel fabrication company folded 2mm steel sheet into the correct shape in 2.5m lengths. We contracted Graham Froud to do the welding and fabrication again. James Cox hacked out the old gutters, while Graham prepared the new folded sections and welded them in place, and manufactured some new down pipes Dave Gravell followed up with a comprehensive painting scheme.


Above : Gutters removed

Above : New gutters

Above : The Tricky area above the ETH overload relay cabinet

Low Power – Replacement of split Bellofram

For a few months, 33012 had gradually been losing power. This had been partially cured by increasing the regulating air from each of the cab accelerator valves. But after a while even this did not work. Testing with a hand-held tachometer proved that the engine was not producing full RPM, which should be 750 RPM under load, 820 RPM no-load. The regulating air pipe work was tested for leaks; with none apparent, attention turned to the governor. A shed air supply was coupled to the main res. and the control gear cut in, with the triple pump isolated. The governor top cover was removed and lift of the speed setting unit measured. Maximum lift at 45psi should be 22mm. It was only 16mm, and there was a definite air leak inside the governor. Sulzer Belloframs are still available from Railpart, we had bought a couple before testing the Governor.

The entire top set of levers, springs and slide valves must be removed, to gain access to the securing screws for the speed setting unit. When this was free, it was dismantled on a cab desk, plenty of natural light! The bellofram was released from its retaining ring, it was spilt around half its circumference. Amazing that it worked at all.

Above : Bellofram :- L – old R- new


The new Bellofram was fitted, followed by its retaining ring and screws, and locking wire.


Above : New bellofram in speed setting unit


The Governor was reassembled and lift measured. This time the full 22mm lift was achieved. Without the air leak, regulating air from the accelerator valves had to be reduced, to give 50 psi full, but no more than 6psi in “ON”. This took a bit of fiddling to get both ends the same.

Above : Speed setting unit back in Governor. Slide valves and levers yet to be fitted

The loco is now back to full power. Just in time for moving 500 tonne ballast and construction trains around the Swanage Railway.


Arrival of 47635 meant that there were now two locomotives on the Swanage Railway with ETH equipment. The SR are gradually reinstating ETH to some of their dual heat coaches. With the aim of being able to dual heat one 5 coach rake by February 2008.

The ‘spoons' “train heat ON lamp” rather concentrated James' mind to finishing 33012 ETH, a process started 3 years previously!

Crompton ETH has only one safety device, an overload relay. No earth fault protection! It is essential that all components and cables are in good condition. While megger testing the electronic voltage regulator must be disconnected.

All loco ETH cables megger tested – all OK, more than 1MOhm.

Control circuits tested, missing jumper cables replaced.

ETH earth cable disconnected from loco frame, control gear megger tested -OK

ETH Generator meggered, while this was within limits, all brushboxes were stripped out and cleaned. The Vee ring a commutator riser were cleaned. The commutator was extensively cleaned, including gently scraping between every single segment. All interior surfaces and field coils were cleaned. The brushboxes were fitted in the order they were removed, brushes fitted – the correct grade of brush for ETH were available. These have one normal segment, and one hard segment, to keep the commutator bright during summer months…

ETH voltage regulator tested for output while disconnected from generator field coils. OK HVR connected.

Then the moment of truth. Would it work, or would there be a bang and the engine shut down?

The earth cable was left disconnected for the first time ETH was turned on. The “TRAIN HEAT ON” button was pressed, the engine revved up, but there was no “TRAIN HEAT ON” indication in the cab.

Testing the ETH output with a decent voltmeter proved that the polarity was reversed, at some point the field connections had been reversed, lack of idents on the cables did not help.

“TRAIN HEAT OFF” Swap field cables, try again. This time the polarity was correct, still no ON indicator – because the earth cable was left disconnected. But when it was, the “TRAIN HEAT ON” indicator illuminated with a pleasant red glow.


Above : Says it all!


It has only been possible to test 33012 on one coach so far, but no problems were encountered.


January 2007

During the early part of the summer, it became apparent that the Carriage Shed at Swanage would be partly taken up with a PMV wagon which was being overhauled. The length of this vehicle would prevent any mark 1 coaches also going in the shed. But a 50' 9” long class 33 would fit! We had been trying to get some areas of rusty bodywork patched during 2005, but with not much success; the Swanage Railway General Manager, was receptive to 33012 going in the shed for bodywork repairs and full repaint. To be funded by 71A Locomotive Group.

There was not much time to think about this, because the Swanage Railway had appointed a part time welder/ fabricator/ painter as of 1 st September, and 33012 was to be his first project!

A contract was drawn up, whereby 71A Members would assist as much as possible with ancillary works.

This included; removal and needle-gunning of cantrail grille covers. Removal of radiator grilles, thread cleaning of radiator grille bolt holes. Drilling out and tapping snapped cantrail grille cover bolts. Removal of windscreens and windows. Needle-gunning, hoovering and priming aluminium cantrail grilles. Removal of handrails - ready for door pillar repairs.

The corrosion repairs were tackled a side at a time, then the two ends, allowing primer to be applied to repaired sections as soon as possible. The lower body side below both side engine room doors was cut away to expose corroded framing behind. This rust grew during the few years that the internal gutters were non-existent.




We did not try to replicate the original BRCW framing, but used angle and flat bar sections to fabricate a new structure, which new sheeting was then welded to.


After the handrails had been removed, it was clear from bulging of the sheeting, that all of the door pillars were rusty. All were stripped for examination and repair. Again, BRCW used carriage style top-hat sections. We used 1” box section. Somewhat heavier that original, but with the added bonus of providing strong fixing for the handrails, rather than adding plates to the top and bottom mounting positions.



New sheeting was then welded to the repaired pillars and into the existing sheeting.





The area above the speedometer wheel-wear adjuster had been bubbling for some years, again due to the lack of internal gutters as few years ago. The following pictures show work in progress to cut away the defective sheeting, what was left of the framing, fabricating new framing and fitting new sheeting. This was the most extensive repair and was carried out by Swanage Railway Apprentice fitter Graham Froud.









The corrosion in this area turned out to have spread to under the cab door opening. This was re-built from box-section, angle and plate. Hopefully the modern anti-corrosive primer will last for many year of protection!




During this repair, we endeavoured to use as little filler as possible, so are very pleased with the finish Graham achieved with the bare steel. BRCW built locos often have a characteristic ‘battleship' look where the outline of framing can be seen through the external sheeting, 33012 is no different. It is a locomotive, where the sides and roof do nothing more than protect the internal machinery. A mirror smooth finish would be difficult to achieve with the Warren-girder construction of the sides.


The 1950s style cab ends did give some challenging problems, a workshop set up for Mark 1 overhauls does not have much in the way of bodywork tooling like dollies and wheels.

To enable ace painter Jason to continue with preparation and painting of the other side and roof, Graham got the short straw to repair the lower section of no.2 cab.




Notice the use of intermittent welds, to avoid heat distortion of the sheeting.


With the welding finally out of the way, attention could really turn to paintwork. This was done following the T&R Williamson painting schedule to the letter. With primer, two undercoat then one gloss applied by foam roller, then lightly brushed to remove roller marks.






With the painting all but finished, 71A members could turn to re-fitting the cantrail grilles, handrails, windows, windscreens, radiator grilles. 33012 should emerge from the carriage shed by the end of January.

The general opinion of everyone who has seen 33012 during its bodywork overhaul, is that we caught it just in time. Had we waited until after another wet winter – it would have needed months of welding, rather than weeks this time.

More photos of the bodywork restoration can be seen here

September 2006

33012 has been taken out of traffic for bodywork repairs and these are to be undertaken by the Swanage Railway on a contract basis with any additional work being carried out by group members.

January 2006

During January we finshed the B7 exam and attended to a number of faults which did not prevent the operation of the loco, but were noticalbe during use. A fault had arisen where the Air train pipe was filling, with both FV3 brake valves in NEUTRAL. A variety of blanking plates and seals were used to isolate various sections of the brake system until the errant valve was identified. This was removed, cleaned and new O rings fitted. If anyone would like more information on this fairly common fault, please contact the 71A Locomotive Group.

After running nearly 10,000 miles since the last time they were painted, during 2002, the white lines on the tyres were alomost invisble. So all wheels and tyres were wire brushed and painted black. Followed by the equally spaced white lines.

Winter 2004/05

At the end of November it was the annual Swanage Railway Diesel day. We try and do something different to the appearance of our loco each year - so we know what year it was in photographs! This time it was fitting snowploughs... This involved acquiring a set of brackets for the centre ploughs, cleaning stud threads on buffer beam and transporting the ploughs from Norden to Swanage for fitting by cover of darkness the evening before the Diesel Day. 33012 was washed and polished by hand to improve appearance.

January is the annual Swanage Railway shutdown. Giving everyone a chance to catch up with maintenance with no train running. 33012 had a number of items attended to:-
Ever since we rebuilt the engine in 2002 we have planned to fit a class 47 style governor oil feed system. This has a separate feed pipe direct from the priming pump to the governor with a relief valve at the connection to the main oil pipe to ensure the governor gets sufficient pressure to operate without cranking the engine for ages. The parts and pipes were gradually accumulated during last year and were fitted during January, there were a few minor leaks to tighten but it was just a case of wait and see how the loco started in regular use. Particularly with the engine at operating temperature with the oil somewhat thinner than when cold.

A long standing messy oil leak was from the governor output shaft seals. These are a pair of rubber ‘O’ rings which harden and flatten with time and use. It is a fairly straightforward job to change them by taking off the top of the governor, removing the output lever and a taper pin, then sliding the whole shaft out of the governor. Allowing easy removal and replacement of the ‘O’ rings. Reassembly is the reverse process.
Other work carried out was; change oil filter elements, fit clips to the new governor oil pipes, hoover accumulated dust out generator.

With re-entry to service it was apparent all was not well with the governor or something associated with it. The engine would not start unless the rack lever was pulled manually. Not something to do too often with the risk of over speeding the engine. It took quite a bit of investigation to trace the fault to the engine run valve sticking. Caused by a build up of insulating material which had fallen off the solenoid. That was another governor top off job and clean out the top of the run valve with paraffin. As a precaution we changed the solenoid for a spare. The one from 33012 will be de-greased and re-coated. The engine now starts better than ever before.

33012 did the usual honours at the Swanage Railway Members Weekend in March, working turn about with steam locos on an intensive service. Routine maintenance continued during the spring with the usual Crompton problems of wipers and cab trim falling apart being attended to. April saw the start of the booked dining trains on Friday evenings and Sunday lunchtimes. We thought we would find out just what could be produced on a Crompton’s Stove – results are here Ahh, Chicken Madras. Try that on a spoon hotplate!

During May, it operated every day for a period of 9 days due to a combination of booked work and charter trains. Another special event was the 120th Anniversary of the opening of the Swanage Branch, an opportunity for all locos to be in action. 33108 arrived at Swanage during May, with the mouth-watering prospect of multiple working. That would wait for another day.
There was cause for celebration during early July, when 33012 celebrated 45 years since delivery from BRCW at Smethwick. As luck would have it, the final Sunday Lunch train of the early summer was booked for a Crompton, so several 71A Members celebrated.

With the onset of summer, we began stripping the rotten hardboard side panels out of no.2 cab. This needed to be done in warmer weather, because the cab heaters would be missing for several weeks. After stripping out the aluminium trim and old hardboard we cleaned, primed and painted the steelwork behind them. It was reassuring to find that the cab droplight drain gutters were intact and actually working. The old hardboard was replaced with oil tempered hardboard, consultation with the resident chippy decided that was the best product. After all, the old stuff had lasted since the Mid- Eighties. The new board was cut to size and fitted. Primed, then painted. Heaters and grilles refitted after cleaning, much of the old aluminium trim was replaced with new. Next summer we will do no.1 cab.

Mechanical attention during 2005 was; adjust tappets, re-make pipework to no.1 exhauster, repair defective wiper motor. Clean out under no.2 cab secondmans DSD treadle. An air leak in the control cubicle was traced to the exhaust choke in the FORWARD EP valve sticking. The EP valve was dismantled, cleaned and re-fitted.

By December, 33012 was due for a B7 exam, the “downstairs” parts of the B7 exam were completed on the pit at Swanage. “Upstairs” was left to be completed during the January shutdown. During 2005; 33012 did just over 3700 miles and worked around 40 booked passenger diagrams in addition to thunderbird duties, stock moves and engineers trains.



Our loco continues to give reliable service at Swanage, there is likely to be an increased demand for the loco next year while SR has many of its steam locos out of service for overhaul. The very popular diesel hauled ‘Booze Cruises’ will continue with an almost doubling of frequency.

Recent maintenance and preservation work has been:-
Replaced defective no. 2 driver side wiper motor, fit new rocker cover/ fuel pipe seals, repaired leaking pipe union on no.1 exhauster tank, re-fix no. 1 cab driver side door catch, B4 exam, re-fit no. 2 cab driver side window finger bar, wash exterior of loco, fit new vacuum hose no.1 end, clean exhaust choke of start contactor EP valve, fit new seal to governor vane motor, fit new crankcase door seals, hoover under no.2 cab floors and prime all metal, replace rotten wooden top tread on R1 steps, clean and prime engine room gutters, fit additional catches to headcode doors.


Engine governors are complicated pieces of equipment and require proper bench-testing facilities for calibration. Therefore, we borrowed the governor from 33034, it having apparently only worked for 18 months before overhaul, unfortunately that was fifteen years ago. We removed the governor from 33034, cleaned and painted it. Then took off the defective one from 33012 and cleaned the end of the engine which is normally inaccessible behind the governor. One of the faults that came to light after the engine work was an intermittent fault with AGR MCB tripping. This sometimes happened when the load regulator was running back with the power handle in ‘OFF’, therefore, when the Load Reducing Solenoid (LRS) of the governor was energised. Upon investigation we found that both positive and negative wires to LRS had broken insulation where they emerge from the conduit. So we replaced both of the wires and AGR has not tripped since.

The new governor was lowered into place and lined up to provide 0.005" backlash on the spur gear drive from the crankshaft. Then oil feed, regulating air pipe and the wiring connected. Finally the fuel control rack was connected and all fuel pumps re-set to the different governor. We started the engine and arranged possession of the line within Norden Station limits for light engine test runs. The engine and governor work very well together and the loco is certainly not lacking in power!

During the first two weeks of February 33012 was used for an extensive programme of running between Swanage and Harman’s Cross with one coach to provide real train operation for training signallers on the new Swanage Signalbox. The loco worked every day required with no faults whatsoever, and carried on hauling passenger trains for most of the ‘Thomas’ week. During the ‘Thomas’ event, we noticed that one of the buffers had a loose head, so 33034 has loaned another buffer. The buffer swap being done on the same day as we changed a leaking bogie damper and defective fuel filter o-ring seal.

Resumption of normal weekend steam services gave the opportunity to use the loco pit for steam cleaning the underframe and bogies. This is a thankless, very dirty task that is vital to reduce the risk of bogie fires. On one of the days of steam cleaning the loco shut down by itself. On attempting to re-start the battery was flat. The loco had stopped charging without anyone noticing. Unfortunately, the Swanage Railway’s loco battery charger is fully ‘plumbed in’, and 12 was too far away for the leads to reach. So we had to arrange for a tow with the 350hp shunter! While waiting for the move to take place, I decided to try a ‘special start’. Suffice to say that the engine started but was still not charging. Suddenly, the Battery Charge Contactor (BCC) slammed shut and the ammeter showed a charging current. We left the loco running to re-charge its battery while fuelling it and ourselves. Suddenly after running for about 1½ hours the BCC dropped out. I immediately shut the engine down as the fault had reappeared. The same voltage pick-up resistor that had caused problems in 1999 had broken again. Or rather that the replacement one we fitted back then had given up! I temporarily repaired the resistor and fitted another spare one a couple of weeks later.

Our loco worked as well as ever over the Swanage Members’ weekend and for our playdays. The only problem to occur was the bedplate drain became blocked. We cleared the blockage with a high pressure air line and the drain now works better than ever. Then the loco has received a bit of housekeeping. Both cabs and engine room were hoovered out and the radiator compartment was gradually cleaned and painted, by that same people who did the rest of the engine room!

A few minor repairs were made; the heat - proof lagging on the crankcase breather pipe has been replaced because the old lagging had fallen apart. The set of bogie steps that were fitted during the winter have had additional fixings to prevent rattling. During June, the loco received a B2 exam.
Ongoing work included; changing a defective slack adjuster, fitting grease nipples to brake rigging, cleaning and re-shaping traction motor contactor tips, leaking vane motor seal replaced.


The first job of the year was to attend to the drivers’ lower DSD treadle, No.1 end which was seized. This is a standard 'Crompton' problem, repair involves removing both the upper and lower treadles and then lubricating the two pinion shafts. the rest of the day was spent cleaning the cabs and checking all levels were within limits. At the end of March we carried out a B8 exam and steam cleaned the underside of the loco and bogies.A recurring leak from the no.1 Exhauster oil reservoir was cured by carefully tightening the pipe union.

During the spring we did some work on the main generator which included freeing the main generator brush ring clamp bolts, barring the brush ring round and cleaning the bottom brush box of an accumulation of grease and carbon dust. The steam lads were perplexed when Dave Axton and James Cox reappeared from the engineroom, both with dirty faces - the explanation that they had been looking in the main gen. was met with horror; "I thought they were supposed to be clean places!" Dave muttered something about "haven't been clean since the day they were built!" Work of a more minor nature has followed recently; the driver's armrest in no.2 cab was loose after being removed on the first of the Playdays, the droplight being closed more energetically than the scissors could withstand... More no.2 cab work saw the striking plate on the L2 door reattached after the screws had pulled out of the hardwood surround.

It is 71A Locomotive Group policy to carry out engine oil sampling at every B exam. These are carried out every three months. Since entering service at Swanage in March 2002 the oil samples for 33012 have shown a very gradual increase in acidity. There is nothing fundamentally wrong with this, being caused by a build up of by - products of combustion. The normal course of action is to continue sampling at reduced intervals until a specified limit has been exceeded. It is then time for an oil and filter change.

However, coincidentally with the oil reaching the end of its life, the wet liner top seals have been leaking more and more. For the first time; in April this year, oil samples had traces of coolant residues. Meaning that the bottom liner seals were starting to leak into the crankcase. We kept the locomotive in service at Swanage and set about planning an engine overhaul. The summer of 2002 being an ideal opportunity following the reduction of our work load at the Mid Hants Railway and the class 20 going away on hire. Besides, it is OUR loco!

The Swanage Railway have become dependent on 33012 for 'thunderbird' duties, stock moves and special trains. As well as helping out on permanent way trains. Their initial problem was "what do we replace it with while the engine work is being done?" Group members set up negotiations between the Swanage Railway and another class 33 group. Unfortunately the other loco was not ready to leave its home railway.
In the meantime work continued apace at Norden to establish facilities for a major engine overhaul. We had ordered a 20' container some months ago and when it was craned into position, Paul McDonald also gave us use of a Portakabin to use as a mess room. Mark Campbell of the SR Electrical Engineering Dept. connected a permanent supply to the Portakabin's existing electrics. Mark has also fitted lights and sockets inside the container. We acquired some water main pipe and fittings and connected the sink and water heater in the Portakabin to the main at Norden Station.

Finally, after working the second of the Firework Nights, 33012 was taken light engine to Norden at shortly after midnight on the morning of 4th August. By 0200 everything was in place. Work began on Sunday morning, the first stage was to remove the small roof section then the rocker covers and pour 2 gallons of diesel over each head to clean the rocker gear and flush the oil passages. After running for about ½ hour the engine was shut down and the batteries disconnected. The crankcase doors were taken off and the oil pumped out of the sump. Meanwhile the coolant was drained into drums for re-use. A hired diesel powered compressor made light work of the assorted air wrenches for removing countless nuts & bolts. With a team on each side of the engine the inlet manifold was taken off, high pressure fuel pipes removed, rocker gear pipework disconnected and rockers removed, push rod tubes disconnected. Meanwhile the high level water pipes were taken off and the exhaust system split into manageable sections and also removed. When all connections to the heads had been undone or removed it was time to undo all 64 nuts from the head studs. All items were stacked in the container for further attention and the tools cleaned and tided. The small roof was replaced and then final teas for everyone.  There was a delay before we could start to crane off the heads & pistons because various shift patterns had to be slotted into the operations of the Swanage Railway - not an easy task. We did not waste the downtime; the exhaust system was completely stripped and the joints set aside for new inserts. The inlet manifold, fuel pump gallery covers and rocker covers were cleaned and prepared. Then primed and painted grey gloss. The driver's windscreen at No. 2 end had been broken by vandals last year, with the arrival of a good one, we changed the windscreen. The fuel pump gallery had a build up of scale and oil sludge, the gallery needed a lot of digging, scraping and washing with paraffin. A few other long standing jobs have also been attended to such as replacing defective window rubbers and cleaning the flaky paint off the crankcase doors.

At last on 28th August people slotted together and met at Norden for an evening of craning; Ron the crane driver arrived and shunted the crane into position with the class 14. The main roof section was lifted off and set on the ground so that we can repair some damaged areas. It has been many years since the heads have been removed and a couple of them were reluctant to lift off the engine. These were loosened with a hydraulic jack and each head lifted off the engine.

The procedure carried out was: attach lifting eyes to head, connect to crane hook. Lift off and jib up. Then swing to right and lower each head next to the door of the container. When a head was next to the door it could be swung through the door and deposited on the floor! It was time for tea after the heads were off and then we set to work on the pistons. The crankshaft has to be barred round so that the piston to be removed is at TDC. Then the big end bolts were undone and the lower big end cap taken out with the spoon. The big end spoon is shaped at one end to support the cap and lugs slot into two of the bolt holes. The handle resembles a shovel handle!

Each piston has a threaded hole in its crown for fitting a lifting ring. To avoid jamming pistons in liners; Ron had to let the engine revs of the 1948 built Stothert & Pitt diesel electric crane, reduce to enable a slow lift. The pistons were lowered next to the container, upended and stood up with the con rods leaning against the wall. We did try to lift a liner out with the crane, unfortunately it was stuck firmly in and was not safe to lift with the crane. Finally the tarpaulin from 33034 was used to cover the loco and yet another 0200 finish!

A week later and we met up to try to jack out the liners. Eventually the system used was: a cut-down piece of sleeper was laid on the respective big end journal at bottom dead centre. The 20t jack placed on top and jacked up against the liner lifting plate. Using this method the pressure was applied a little at a time until the liner moved up and was jacked free of the engine block. We jacked out all 8 liners and started to devise a safe system to lift the 30" long liners out of the block. Eventually it was possible for two people to stand on top of the engine and lift the liner with a strop round a bar. When the liner was clear of the engine top a piece of wood was slid under it to support it. The next stage was to lift the piece of wood with the liner on it and lay the liner on top off the head studs. It was a simple(!) procedure to roll the liner down the side of the engine and into the side doorway. The liners were also stacked in the container in the space that had been created by putting the painted items in 33034!

Then we spent time drilling out some snapped roof catch bolts and re-tapping the brackets. The inlet & exhaust studs on the heads have been cleaned with die nuts. The fuel pump gallery was still very dirty so we decided to remove the push rods and fuel pumps to properly clean the engine block. The fibreglass roof was sanded ready for repairs and coating with clear epoxy to seal the surface. While we took turns to lap in the liner and engine block mating surfaces, other work continued around the loco. The fuel pump gallery was very dirty with years of accumulated grease and scale, so all eight fuel pumps were removed and cleaned. Next, the push-rods and cam-follower housings taken off, the cam followers being fitted with new rollers where necessary. Both the oil and fuel pipes in the gallery were disconnected and detached, then cleaned and painted their respective colours; ‘Espresso Delight’ (brown) for fuel and ‘Cracked Clay’ (pink) for oil. Then the fuel control rack was removed. With the gallery stripped it was possible to properly clean all surfaces and then paint it. When we loosened the roof clamp bolts, about half of them had sheared. So, the snapped bolts were drilled out and the holes retapped to ½” BSW, the ones which fasten the exhaust shroud to the stack were extremely tough, they had been heat hardened by the hot exhaust gases. After removing the heads, we found that the transition bushes were badly pitted and corroded. We only had enough spare ones to replace about half, so the best of the original ones were shot blasted, primed and painted. The depressions in the engine block where the bushes are fitted were machined to remove corrosion and pitting. A modification was made to most Sulzer engine liners to machine a flat area all round, between 2 O - ring seals. This was done to fit a strip of nylon 1" wide all round to provide a rubbing surface, rather than metal to metal. The nylon ring is called a ‘fret’ ring. However, not all of the liners in 33012 had been done, but as six of the eight on 33012 did have this flat area we decided to have the last two machined to match. The Swanage Railway were happy to do this work for us.

All piston rings were removed, cleaned and checked for wear with a ring the same internal size as a liner bore. A few were worn and thus replaced. The grooves in the pistons were also cleaned. The big end bearings were mostly in very good condition so were topped & tailed to put the perfect bottom shells on top, the top ones doing the work.

Eventually when all the lapping and cleaning had been done, it was time to put it all back together. Ron arrived on a Sunday afternoon and used the class 14 to haul the crane across the Arne road and next to 33012. While Ron set up the crane, we gathered all the tools and equipment ready for fitting the liners. Each liner was picked up from just inside the container door and lifted a few feet off the ground. When at working height sticking self adhesive Gore-Tex tape around the top of the liner was possible, just under the mating surface, also to fit the three new O - rings. After each liner was prepared, it was lifted and swung over above the engine, then carefully lowered into its respective position. Just before the liners were lowered, a bead of sealant was applied to the top mating surface of the block, then a new soft iron ring fitted. With the weight off the crane, the next job was to jack each liner fully home using tubes over some head studs and winding on nuts and washers carefully. This procedure for all eight liners took all of the evening and we packed up at 0200 the following morning!

After varying amounts of sleep, the team met up again the following afternoon to fit the pistons and heads. Unfortunately the class 14 decided to give problems, with its control MCB tripping when the engine was started, on the ninth attempt it held and the engine stayed running, one for the future...
For the 33, the pistons were all ready to go and just needed a lifting ring to be screwed into the lifting point in the crown. Each piston was slowly lowered into its place using a guide ring to ease the rings into the liners. As soon as each big end was resting on the crankshaft journal, the bottom big end caps were lifted into place with the spoon and the four bolts slid through and nuts assembled finger-tight. Next, each head was finally prepared for fitting and each was fitted on top of new transition rubber seals. The transition bushes allow coolant to pass from the engine block water jacket to each of the eight heads. There are four bushes per head. Eventually the lifting was finished and that was the last of the floodlit work!

With the heavy lifting done, we set to work to fit and tighten the 64 head nuts to a torque of 750 ft/lb. Then the coolant pipework was fitted with new joints and the system filled to test for leaks. After tightening a few jubilee clips, the cooling system was sound. So we continued by fitting the 16 pushrod tubes, then dropping the rocker gear into place, attaching rocker arms to pushrods, finally tightening the rocker gear down. The exhaust system was assembled piece by piece onto the heads, with new ‘Metalastic’ joints, heavy duty spring washers and nuts. All the fuel spill tubes and oil feed pipes in the gallery were reconnected. The big end bolts were tightened, these being pre-stretched so the required torque is applied when lines on the nuts and con -rods meet. While the engine was being barred over for access to big ends, the tappets were adjusted. A long-standing oil leak from a crankcase door was cured by replacing two missing studs. Unfortunately the stud holes in the block had become enlarged so much that ½” BSW threads were too small. So we chose to drill out the holes a fraction larger, tap a 5/8" BSW thread into the block, then fit studs made by turning 5/8" bolts down to ½” and then die-ing the ½” BSW thread.

Eventually the day before start-up arrived. The sump was cleaned out yet again and new oil pumped in. All remaining pipework was fitted and the oil system primed and pressurised for leak testing. After tightening a few banjo bolts the system was sound. At last everything was ready for attempting to start the engine, however we had set a date of Sunday 10th November for this so that as many active group members as possible could witness the event. So all that remained was to charge the batteries and make a start on cleaning the engine room and cabs of all the various tools and equipment that had accumulated over the project. As luck would have it, The Railcar Association were holding their annual DMU Convention at Swanage that weekend, so we chose to start the engine at 1200 when the DMU would be at Norden. Thus providing a ready-made audience of about 30 people, who are more interested in Diesel rail traction than the average passenger. During the morning we top up charged the batteries, finished clearing out the engine room and cabs and completely removed the tarpaulin that had served us so well (the first one disintegrated!). Eventually the hour arrived, we had already asked the DMUs driver to stop as short as possible to allow plenty of viewing space on the platform. With Dave in his usual position holding the fuel rack fully open and me on the engine room start button, we cranked the engine for what seemed like ages. There were smoke and fumes emitting from all sorts of places. Just when it looked like it was not going to start, a couple of cylinders began firing and then they all joined in, the engine stayed running by itself to a round of applause from the assembled audience.

The engine was left running for a few minutes to check all cylinders were firing properly and then shut down. Next, the camshaft side crankcase door was taken off to check all bearings for overheating. None were. So the door was replaced and the engine started again and run for about 40 minutes. During this time we tightened various fitting and did some fine tuning of fuel pumps and tappets. Then the engine was shut down again and left for 15 minuets for fumes to disperse, the door taken off again for further checks. Everything was in order so the crankcase door was replaced, followed by the inlet manifold and rocker covers. With everything in place, the engine was stated up again and Dave drove 33012 a few feet in each direction to check the controls that had not been used for 3 months.

The Swanage Railway had, a week before our start up, been given certification for their ‘new’ Hiab crane, which is mounted on a 4-wheeled wagon. This had been coupled to one end of ‘12 during the week ready for us to use. First, the wagon and loco were positioned on separate roads at Norden. Then the loco’s fibreglass roof was lifted by Hiab and swivelled round until the roof was suspended over the road that the loco was on. Then ‘12 was driven under the roof and the roof slowly lowered into place. Next, the wagon and loco were coupled for driving onto the road/rail pad. At the pad, it picked up the diesel powered compressor and placed it on the Hiab wagon. Then drove it all down to our Depot and unloaded the compressor. Loco and wagon were rearranged so that the Railway could pick up the Hiab wagon. The final job of the day was to fit a few of the roof catches to stop the roof blowing away! and to fit the exhaust cowl. That was the end of a successful and rewarding day for those lucky enough to have been involved. Over the next couple of weeks we cleaned the cab and engine room floors, replaced the raw water with antifreeze mixture and carried out a B1 exam ready for the Swanage Diesel Day.

Following the engine overhaul, 33012 completed a number of test runs and then the Swanage Railway’s Diesel Day with a few faults coming to light. As would be expected after major work. In the control cubicle, all the contactor tips needed a good clean after the 3 months out of use. Therefore we started the B exam sequence off with a B1 during December. This includes; inspection and lubrication of traction motors, auxiliaries and generators. Bogie cleaning and lubrication, cubicle exam. Late in December the loco was reported with low power, on investigation this was found to be caused by the governor not working correctly, not operating the fuel rack as much as it should be.


A  major project undertaken over the first three months was the complete replacement of all 12 removable cab floor panels. What happened was: the new water resistant ply was cut to fit the opening in the existing wooden dividing pieces, allowance made for the aluminum angle trim. The next stage was to cut the new grey lino to size. The flooring suppliers I used assured me that the best product for a diesel locomotive with oil, fuel, grease, mud, ash, chalk, water, fag ends, tea, coffee all likely to end up on the floor; was old-fashioned linoleum. This has the advantage of being extremely tough and able to be cleaned with paraffin. When the lino was ready the adhesive was spread evenly all over the ply and allowed to soak in for a few minutes, then the lino was placed onto it and pressed down firmly all over. After a few more minutes, pressed down again. After this, the ½" aluminium angle was cut to length with the ends mitred; then drilled, countersunk and screwed into the edges of the ply. The final piece of each panel was the brass lifting ring, fitting this required a circle of lino to be cut out and then the ply chiselled to let the ring sit flush to the lino.

The aluminium and lino tread plates under the cab doors were removed during the body repairs to enable the steelwork under them to be repaired. We used smooth planed oak for these to sit on, oak being almost rot-proof and nearly as hard as steel. We had to grind off some off the welds to let the plates sit low enough to not foul the doors, we took the opportunity to sand the door edges and frames to let the doors open and close easily, a task that has been outstanding for many months. Where the sub-floors are, in places, not completely flat - the actions of 40 years of drivers - we have had to drill & tap the sub-floors as soon as possible to pull the panels down to not foul the bottoms of the inward opening doors.

Many years ago the loco suffered a small fire in the no.1 cab instrument panel, the damaged lighting wiring had been made safe(ish) by Stewarts Lane Depot. Only 2 of the 6 light bulbs were working, so we re-wired the circuit and fitted 4 overhauled bulb holders.

While in service at the SR Members' Weekend 24th/25th March, the loco nearly suffered its first failure in preservation when a terminal stud snapped off the back of the TWR12 relay. This relay supplies 110v to '12' wire which itself feeds the control circuits of most of the auxiliaries like the compressor and exhauster high speed. As luck would have it, the locos Team Leader was on board at the time who was able to effect a temporary repair within a couple of minutes and later that day replaced the relay with one borrowed from 33034.

No.12 failed for the first time in preservation on Saturday 21st July with an oil leak. Shortly after start up for an evening DMU drag, two crankcase door studs were found to have sheared. This is common Sulzer problem caused by vibration of the aluminum door creating metal fatigue in the studs. All that normally results is another small oil leak, but in this case the 2 studs were at one end. Leaving a corner unsupported. Hence at least 10 gallons of oil were lost in only half an hour.

Firstly the door is taken off, then a small hole drilled through the centre of the snapped stud. This relieves most of the tension and the stud can be easily unscrewed with a small flange that remains.

During the autumn and winter; engine room cleaning and painting continued apace. All cantrail grilles have been scraped and painted gloss black - that's the colour they end up anyway. Almost all of the power unit has been degreased, primed and grey glossed, only the turbocharger and both ends of the engine remain. At last, the internal gutters have been repaired or replaced,

On the engineering side; we changed another split rubber pushrod tube, which involves removing the appropriate rocker cover, disconnecting the pushrod from the rocker. Unscrewing the bottom section of the tube from the fuel pump stand, then lifting, juggling and sliding down the entire pushrod and tube assembly. The old spilt rubber section was cut off and jubilee clips undone. Then the new rubber tube was fully slid over the top steel tube, then the pushrod slid back up into position. All connections re-made and tappet adjusted. Then topped up the engine oil level to replace what had been lost out of the old split tube.

For the Diesel Day we tidied up the loco. The underframe and bogies were degreased and steam cleaned, then the body brush - washed and pressure washed. While the paintwork was polished with an oil/paraffin mixture, the axlebox covers were painted yellow, the bogie springs red and dampers blue. The last areas of external electrical conduit were painted orange and the battery box safety catches yellow. The final finishing touch, under the cover of darkness was a full set of silver faced buffers!

With the onset of cold weather, the coolant was topped up with antifreeze, somewhat easier than last time - thanks to a compressed air powered diaphragm pump. There had been an intermittent AWS fault for a few weeks. When the fault became permanent I was able to trace it to the no.1 end Baldwin Valve being stiff. After lubricating with brake valve grease, it works properly again.

 All 4 bolts on the stowage bracket for the 27 way jumper cable had stripped threads, We removed the bracket and cut off the old bolts. Then knocked out the remainder and  welded new bolts onto the bracket. When it had cooled down, re-fitted the bracket and new wingnuts and washers.

A recurring leak from the no.1 Exhauster oil reservoir was cured by carefully tightening the pipe union

One of the final jobs of the year was freeing the main generator brush ring clamp bolts, barring the brush ring round and cleaning the bottom brush box of an accumulation of grease and carbon dust. The steam lads were perplexed when we reappeared from the engine room, with  dirty faces - the explanation that we had been looking in the main gen. was met with horror; "I thought they were supposed to be clean places!"


On 2nd January 2000 the Swanage Railway put the batteries on charge, then we  attempted to find a major wiring fault that had appeared. Basically when the master handle was moved to EO, the SC (start control) relay was energised without pressing either of the cab start buttons. There had been a section of lower body side replaced close to a main control wiring route, at the no.2 end so this seemed like an obvious place to start. Additionally, the CN (control negative) MCB in no.2 cab was tripping in EO.

We spent 5 hours taking up no.2 cab flooring and some engine room floor, then disconnecting some of the wires whose circuits were suspect. Everything appeared sound. So eventually we decided to find out what happened in no.1 cab. With the handle in EO this negative MCB tripped repeatedly. Suddenly there was a  burning smell coming from under the no.1 cab floor, so we quickly turned everything off and took the flooring up. There, at the bottom of a bundle of control wires were 6 or 7 wires with the insulation completely rotted away and the copper cores short circuiting and touching the steel cab underfloor.

At least we had found the problem and there was no real urgency to repair the damage while the paintwork still had a few weeks to go. So we removed the fire alarm fuse to try to prevent the batteries from being discharged. The charger was disconnected the following day after about 30 hours for the loco to be shunted back into the carriage shed for the bodywork overhaul to continue after the Christmas break.

Painting continued in no.2 cab while I separated the tangled wires and cut out the damaged sections and replaced them with new 2.5mm2 stranded wire. With the triple pump fuse still removed we set each master switch in turn to engine only, forward and reverse. All relays and contactors operated correctly and no more CN tripping. So at another Sunday work party we put the triple pump and fire alarm fuses back in and started the engine. After about a minute I looked out to see what colour the smoke was... It wasn't smoke; it was raining, no it wasn't rain, water was coming out of the exhaust. Oh dear! (you know what I mean) the turbo drain was blocked. Shut the engine down NOW!

As the exhaust points directly at the sky it is possible for rain water to enter the turbo, fortunately Sulzer engines have a drain pipe to allow this water to drain harmlessly away. Unfortunately the pipe follows a convoluted route before it passes thorough the floor. We dismantled  a union in the pipe and covered the engine room floor with water. We could push a piece of wire up or down the pipe and reach an obstruction. A length of welding rod was stiff enough to shove down the drain pipe and push out a lump of muck, followed by some water. We connected an air line and blew the pipe out with 120 psi and reconnected the drain pipe.

If the water had entered any of the cylinders the engine would have been damaged immediately we attempted to start it the first time. The locomotive had been in the carriage shed for all of January, so the rain could only have accumulated during December. We started the engine again and everything was fine.

Now that the engine had been fired up and the control circuits repaired we could continue to repair and overhaul components before the loco entered service properly. So on to another acronym, this time DSD (driver's safety device - deadman). All four valves were disconnected from pipework and removed. A large plunger transfers the force from the treadles to the valves. These plungers tend to seize with lack of use, then when a treadle is depressed the weight applied is enough to move them to the 'on' position and stay there. All four plungers were taken out of their tubes and cleaned and lubricated. Some of the treadle mechanisms had seized as well but these were all freed off and the plungers and valves replaced. All four tested correctly with the engine running and train pipe at running pressure.

On Saturday 18th March we checked the batteries, started the loco, got it over the loco pit, finished the traction motor greasing we could not complete last November. Then back off the pit for some test runs in the evening. Everything was successful so we  handed  the loco over to the Operations Department for Driver training.

During the fault finding for the wiring defect in January we had disconnected the wires for the speedometer and SSF (DSD Speed Switch) under No.2 cab floor. As driver training was imminent it is useful to have the speedo working in each cab.

After re-connecting the SG1&2 wires we took the cover off the wheel wear adjuster box and connected some battery cells to the output to the speedo display heads. With 12 volts the no.2 speedo showed 40 mph. Unfortunately no.1 speedo did not move. The AVO proved that 12 volts was getting up to the connections on the rear of the no.1 speedo so obviously that was defective.

There is always a risk of damage to windows & glass when preparing bodywork with needleguns and sanders and a windscreen and side window were broken during the final stages of preparation. These were changed. When the loco body was painted there were still some outstanding items like pipes and cocks that needed painting. As well as some over spray on the fuel tank and air receivers. While this finishing was going on it was decided to fit ETH jumper cables to each end so that the boxes and plugs could be painted orange.

With the loco in traffic at Swanage we knew that the fire alarm system should be operational. Even if only to shut the engine down. The detection system was bypassed when '12 was at Eastleigh so we could start the engine on the day we bought it. The original wiring in the hollow roof section had corroded and broken in a few places and all 5 detector holders were rusty. So we used what was left of the old wires to pull through new cable, although one section required the use of a draw tape. Then we fitted up 5 overhauled detector holders.. To prevent any problems with corrosion in the future all bare cable ends were dipped in copper grease before being attached to connectors. The detector holders were assembled with either copper grease or Vaseline to aid maintenance. After some fault finding the circuit rang through correctly and was broken when any one detector was removed.

Next was anti-slip brake switches that had fallen apart.. When the terminal bolts snap after being weakened by corrosion there is a risk of CN mcbs tripping if the buttons are pushed, caused by live terminals touching part of the loco body. Even worse, PB may trip and cut out the compressor, exhausters, ETH and cause an SSF brake application. All 4 ASB switches were rebuilt with new 2BA studding and reassembled and adjusted.

Class 33s have an automatic fire detection and suppression system. With 2 relays permanently energised - fine if the loco is used regularly, but not so good on a preserved railway where the loco can be stabled for a couple of weeks or more. So we  fitted 33012 with an additional rotary switch on the cubicle that can be locked with a padlock. This switch breaks the circuit between the battery and the fire alarm relays, saving the batteries. Some other 33 Groups have re-wired the Fire Alarm circuit via the Battery Switch, but we feel our method keeps the Fire Alarm separate from the rest of the electrics.

The SR does not currently have any AWS installed but it is nice to have everything on the loco working, so we reinstated the AWS. Amazingly all that was needed was a voltage converter to replace the one that had been removed at Eastleigh and a relay unit as the old one did not work at all. The receiver was also changed because the existing one was cracked. After the usual cleaning of bell contacts the system works perfectly with the test magnet.

D6515 did  have a minor fault when the coil of the No.2 exhauster contactor stopped working. This meant that only one exhauster worked, and no high speed. We changed it for a spare and the Swanage Signal Manager has re-wound the old one to go back in the spares.

The loco received a B2 exam as scheduled at the end of September and we changed the brake blocks. A number of niggling problems were also attended to; in no.1 cab the secondman's side droplight had become detached from the scissor mechanism and would only stay 'up' when wedged with a paddle. The driver's side door of no.2 cab also had a defective droplight mechanism that had actually pushed the bottom of the door out! both of these windows have been repaired and work correctly.

We managed to apply a BR lion holding the wheel standing on the crown emblem to one side of the loco in time for the diesel day. Fortunately the photographs that appeared in 'Traction' showed the finished side.

Regular 'B' exams include a visual examination of the generators and motors of the loco. The triple pump motor has been contaminated with oil. We have cleaned the brush-ring and freed off the brushes but there was no real indication of where the oil was coming from. Until the Swanage Diesel Day, when I noticed that engine oil was running out of the bottom of the oil & fuel pump gearcase. As the engine warmed and the oil pressure dropped the drips stopped, at least we now knew that the oil priming pump was leaking. We have changed this with a good spare one and cleaned the motor.


The restoration of '12 had been on the 'back burner' since she was first started in our ownership back at 0124 on Wed 26th March 1997.

We dug out our spare blower motor and put it in cab no. 2 of '012. Well sort of put, because in September 1998 we used the Ropley wheelbarrow, then  lifted/rolled the motor onto a commonwealth bogie in the new shed road next to the loco. The next stage was to drag it along a handy scaffold plank across the bogie and then over the gap to the loco and in thorough the cab door.

The AVR was disconnected and unbolted from its cradle and set to one side. We removed the AVR cradle, then the grilles, fan snails and fan impellers and these were cleaned and painted while the dud motor was winched from its mounting with the small block and tackle, suspended from a scaffold pole resting on sound sections of internal gutters.  We used the same system to lift the replacement motor into place, then the snails, fan impellers and grilles were replaced, followed by the AVR on its cradle. Connecting would wait until the next time.

On Good Friday we turned our attention to trying to charge the batteries. After checking the acid levels in all 48 cells the charger was connected. Charge remaining in the batteries was so low that the cubicle lights had to be left on to give the automatic charger any load at all. The cooling system was filled with water and tested for leaks, while filling we removed a couple of bungs from the oil side of the heat exchanger to check for frost damage.  Thankfully everything was sound.

After the cooling system was filled. We checked the engine oil level. This was not even touching the dipstick, by improvising with a piece of plastic we found that the oil level was ¼" below the very tip of the dipstick. Now Sulzer engines have a reputation for leaking a bit but it must be at least three years since any oil was added to '12.'. Forty-five gallons later by jugs the oil had reached the 'MAX' mark on the dipstick.

Eventually it was time to run the triple pump to check the pressures, everything was good so it was a quick tidy up while we let the batteries recover on the charger. Two blown charger fuses later it was time to attempt a start. Unfortunately the engine was too tight for the batteries to turn it.

After a tea break while the charger did its duty we thought it be worth another try at starting. Well it did start.

Although the engine would start, this had to be achieved using a little trick because none of the start buttons would actuate the start contactors. We suspected this to be dirty interlock contacts somewhere in the 'start' circuit that would need tracing through with a schematic diagram. Another problem was that the engine would not stay running by itself. This again would be dirty contacts in the 'run' circuit. Once a week until the next full work party the charger was disconnected and the triple pump run for twenty minutes to give the batteries some work, then back on charge.

At the next work party we set to trace the fault in the starting circuit. This was found to be dirty contacts in two relay interlocks, namely SC1 (starting control) and M (motor auxiliaries). The engine will now start on the buttons. After being on charge for a couple of weeks after starting for the first time in '99 the batteries had recovered sufficiently to run the compressor to 40 psi. Then to start the engine without going back on charge after running the compressor.

While running the engine on the rack, it was noticed that there was no water pressure at all - meaning that the triple pump had stopped. To give more cause for concern the triple pump would not run again on EO after the engine had stopped. This was traced to a stuck interlock slider on the AGR (auxiliary generator relay), and the pump would run again in EO.

Another problem was that the battery charge contactor (BCC) was not closing although there was an output from the AUX. Gen. sufficient to run the blower motor which works perfectly. Testing with the AVO suggested that the contacts on the Reverse Current Relay (RCR) were badly corroded. WD40 and a few taps with a screwdriver in the time_honoured fashion and the circuit was complete. The RCR is a device that senses that the voltage output from the AUX. Gen. is higher than that held in the battery and energises the BCC. If the AUX. gen voltage was lower than the battery voltage current would flow the wrong way and  motor the AUX. Gen.

At the next Sunday work party we carefully studied the schematic wiring diagram and could see there was supposed to be a resistor in series with the WPC relay coil. This had to be somewhere in the cubicle and after much searching of cable labels we found the two ends required. But there was no resistor where there should be, therefore no triple pump when the engine was running. A replacement resistor was installed and tested OK.

After the initial good news about the battery cells we were disappointed to find that they would no longer take charge or turn over the engine.

A week of on and off charging and triple pump running was followed by another Sunday on '12. Hydrometer testing of the cells showed that the majority were holding a good charge. The class 45 provided air and 33012 was successfully started to much relief. Unfortunately it would not stay running but at least the triple pump stayed on.

The only parts of the 'run' circuit that had not been checked were the Oil and Water pressure switches. These are located in the engine gauge panel, and like the rest of contacts so far were corroded and dirty. Simply squirting with WD40 and moving the contacts cleaned them to shiny copper and we were ready to have another attempt at starting.

This time the engine stayed running for the first time in two years. The BCC closed and the battery ammeter went into the magic charging side and the AVR pointer moved to the usual position at idle.

For some reason we stopped the engine after about twenty minutes, I think it was to find out if the stop button worked - it did.

An hour passed while we check the SG of the battery cells again and it was time to attempt another start. While the engine started and ran for a few seconds it stopped again, even with the rack held open. An inquest decided that the only thing that can stop a diesel engine like that is fuel starvation. We cleaned the fuel strainer and changed the fine filters and ran the triple pump to test for leaks and bleed the system of air. So it was now the moment of truth; the engine started, the rack opened and it stayed running!  By now a very small audience had congregated to see how long the engine would stay going. We kept a close watch on the temperature and pressures while the engine slowly warmed and everything appeared fine.

 In addition to all of the wiring testing and switchgear cleaning the loco we cleaned up the engine room and cabs. The blown up blower motor was dragged across cab no. 2 floor and rolled out onto a pallet resting on the empty oil drum. The pallet and motor were simply lifted (by four of us) off the drum and carried down to the spares coach for winching in.

Almost every cab knob, switch and lever had seized or was stiff to some extent and liberal use of WD40 meant that most things now work, some switches had disintegrated and had to be replaced by spares.



It goes 'Brrruuummm'

We had proved that 33012 would start, run and charge reliably so attention next turned to the power control circuits. Unfortunately the control cubicle had suffered from corrosion and a number of studs on relays had snapped. This took two of us a day to repair with spare relays and new studding.

After we had repaired the damaged circuits we attempted to test the power control circuits. By tripping out the main generator field MCB it is possible to set a change end switch to 'on', master handle to 'Forward' or 'Reverse' and open the controller without any amps being supplied. At the first try we succeeded in making the reversers work and getting a bright blue light.

Now we knew that the batteries were charging, the engine was barely warm and the blower motor was definitely running so the problem must have been PCR (power control relay). PCR is energised via the vacuum and train pipe control circuit governors among other interlocks.

Our experiences with the oil and water pressure switches had taught us that type of pressure operated electro-mechanical switch is prone to contact tip corrosion. The vacuum and train pipe control circuit governors underneath the No. 1 cab desk operate in a similar way. These had both seized solid but the usual treatment with WD40 and manually working the  mechanisms restored them to working order.

The power circuit would now ring through all right but before we started the engine I removed the triple pump fuse and tested that PCR and X1 relays closed when the controller was opened in FOR and REV. These both operated so I replaced the triple pump fuse and started the engine. With the main gen. MCB tripped out we could see that; the reversers operate, motor contactors close, PCR and X1 close. And when I moved the controller past notch 1 the engine went Brrruuummm, meaning that the engine speed valve (ESV) worked.

Although Exhauster no.1 would run successfully, No.2 would not and the high speed did not work. The power control circuit runs through interlocks on the exhauster contactors and the damage to this area has caused the fault with the other exhauster. We had to change XC2 (exhauster contactor No.2) completely because the snapped off terminals are part of the back plate. Typically the entire relay has to be dismantled to remove it from the board, and then reassembled once the back plate had been replaced.

With the power control circuits now restored but the loco at the wrong end of a siding full of vehicles we overhauled the cab controls and instruments. All panel lights, headcode blinds and lamps, cab heaters, brake valves, master handles and power handles we tested and replaced or overhauled as necessary. The fire alarm bell was missing from No.2 cab so anther item from the spares..


'It Works !!!!!'

The next stage was to get the air receivers tested and certified.. The 17 air receiver tanks are distributed under the loco, around the engineroom and under both cab desks, which need dismantling to gain access to the AWS and DSD timing reservoirs. This gave  us an opportunity to clean out any accumulated rubbish and dust under the desks.

We had begun to leisurely remove some of the air tanks from '12 at spare moments in our work parties. Then on 29th September we  received a 'phone call from the Operations Manager of Swanage Railway - "the low loader's booked for Wednesday 6th October". This meant we had 5 days to clean out and remove the unions from the air receivers ready to be inspected on Monday 4th. On the same day the eagerly awaited new batteries would be delivered and fitted.

All air receivers passed the testing but the rep. from Pb Batteries wanted to see that the engine would start after the new cells were fitted. So we had to blank off all off the pipe connections where air tanks were missing so that the main reservoir would pressurise.

The loco had not moved under its own power since December 1996, and we were left with just Tuesday 5th to re-fit the 6 removed air receivers (the remainder could wait until the loco was at Swanage) and pressure test them. We fitted the auxiliary reservoirs above the fuel tank and put the bedplate drain back together then fitted the AWS & DSD timing reservoirs under each cab desk. There were a couple of pipe unions that needed tightening.

We allowed the main res. pressure to build, carried out brake tests and cleared the cabs of various tools and bits of pipe and it was time to finally see if the loco wold take power.. With the straight air brake fully on I pulled the power handle back to 'ON' and the ammeter climbed to 500 amps, then opened the power handle a bit more -  up to 1000 amps and then back to 'ON'. Then ammeter stayed at 1000 amps, even tapping it didn't help, but after a slight adjustment to the controller valve linkage everything settled down.

The next stage was for our resident video expert to tape the first moves under its own power. When everyone was ready I released the brake and opened the controller, the loco moved smoothly down the yard. We had to wait until later in the afternoon for access to the Mid-Hants line to Alresford so we had a pleasant afternoon driving up and down Ropley yard with all sorts of headcodes displayed. The engineroom of '012 was loaded with the remainder of the newly certified air receivers ready to be swapped at Swanage. After arrival at Alresford in the road/rail siding we shut down 33012 ready for loading onto the lorry the following day.

After a protracted road journey, 33012 arrived at Norden on the Swanage Railway and was unloaded by a steam loco! When everyone had made it there and the Swanage daytime trains had finished, the staff was returned to Norden by road for 33012 to work its first journey to Swanage - light engine. We felt it wise to slowly enter the platforms to make sure that the loco would fit along the railway! On arrival at Swanage someone suggested taking a set of coaches on a test run, time to try the vacuum system then! 33012 darkened the Dorset skies well that evening on its round trip to Norden and back before being stabled.

We always planned to do whatever was necessary to 33012 for it to be driven from Norden to Swanage upon arrival at the Swanage Railway. They have given  home to diesel locos in the past that have been delivered as non-runners, and after a few months would sort of cough and splutter and then shut down. Never to be used again.

This performance again would have not impressed,  fortunately 33012 worked far better than expected on its first day at Swanage. During the return 'test run' with four coaches the Operations Manager asked us if we could provide the loco for the Railway's Diesel Day on November 28th. Could we? Of course we could.

There were still the remainder of air receivers to be exchanged; the traction motors and bogies needed oiling and greasing, and we had noticed that radiator cooling fan was not running. The engine got fairly warm on just one return test run so it was imperative that the fan would work for a busy day hauling trains, especially on the locomotive's debut in preservation.

The fan is driven hydrostatically by an engine driven pump which drives the fan motor. This system is controlled by a thermostat valve in the cooling system and these valves can seize and not turn on the fan. The one on '12 had opened by itself so the most likely problem would be that the system was low on oil. We turned our first attention to filling the system with 10 gallons of oil and then starting the engine. I wound in the thermostat override screw a few turns and the fan turned slowly. By revving the engine on the controller we could see that the fan sped up as the engine speed increased.

We swapped the last air receiver then over the last weekend in October we ended up giving the loco a complete B1 exam in preparation for its debut on 28th November. This is a check that all oil and grease levels are correct and anything that may wear eg. carbon brushes is within specified limits. During this B exam we repaired the leaking water pressure switch and gauge feed pipe from the triple pump.

In addition to the mechanical work, we assisted the Carriage & Wagon Dept. with the bodywork repairs. We removed the wipers so the cabs could receive attention, then we lifted the cab flooring next to doors to allow access for any welding required in those areas.

Although the bodywork still had few weeks work left the loco was mechanically 'ready to go' so on Saturday 27th November all we thought we would have to do was top up oil and water levels and grease the traction motors. You never can trust anything to do with railway technology because as soon as we started the engine to move '12 on the pit I saw that the batteries were not being charged. Although the engine stayed running this required further attention. In the low tension part of the control cubicle the BCC (battery charge contactor) and the RCR (reverse current relay) were jumping open and close and arcing. We shut the engine down immediately and started to trace the fault. Clean the RCR contacts & restart, no, still not charging. Clean the AVR segments, no, still not charging. All relays and interlocks rang through on the meter alright until we came to the RCR voltage pick up resistor. This resistor had a reading of 4 Mega-ohms or air, effectively.

I removed the resistor from the back of the cubicle and attempted to find where the wire was broken. The AVO meter showed that the resistor was broken under two clamps. I removed the clamps and rewound the wire round the ceramic to by-pass the broken section and put the clamps over these sections. The resistor would now ring through OK so we put it back in place and reconnected. The only reason we could find for the resistor to fail was that it was already very corroded. The grinding and welding that had been done to renew the rusty door pillar at the back of the cubicle in no.2 cab had covered the resistor with iron filings that had rusted on the very damp night of Friday 26th.The rust had weakened the resistor wire further and eventually it broke.

Started the engine again and; success, RCR & BCC closed and charging at 120 amps. We left the engine running for an hour an a half to try to charge the batteries that were by now low because of successive starts. All we could do now was shut down and wait until the next day to find out if it all still worked. So on the morning of Sunday 28th November we started the engine and made sure that the charging circuit was working, then handed over to the driver to carry out brake tests.

It was now time to go down to Swanage station to collect the stock and shunt it into the platform. After this it was a wait of 45 minutes until the booked first departure at 1030. By now we there were quite a few group members at Swanage).

Shortly before departure time the loco was named 'Stan Symes' as a tribute by the Swanage Railway to thank  Stan for the training and driving he has done since the very beginning.

At 1030 the Guard gave the tip and 33012 carefully hauled its first loaded train in preservation. Its first passenger train since 2nd December 1992, a full 7 years previous. There were a few rude comments from photographers about the loco appearing in red primer with tape over rust holes but the welder did not want to remove the windscreens to repair the surrounds until after the diesel day. They may have had problems making the windows fit.

The loco was booked to work two round trips between Swanage and Norden in the morning, then an hour layover at Swanage while the railway's 350hp shunter worked a demonstration freight train to Harmans Cross and back. Then 33012 worked two more round trips in the afternoon followed by a short freight to Corfe and then light engine back to Swanage shed. We were extremely happy with how '12 performed on the day with no faults that we did not already know about - AWS, DSD etc.

As the report card for the day said: Driver; S. SYMES, loco number; CROMPTON (well it didn't say on the side), Diver's comments/defects; A PERFECT DAY.

With the onset of winter and the possibility of very cold weather it was time to treat the cooling system with antifreeze. During the previous winter it had been drained but there is always a chance of some pockets of water being trapped. The first stage was to drain the existing raw water and flush the system. This was slightly more difficult than normal because '12 was in the Carriage shed undergoing some welding. We had to pipe the waste water outside into a drain. When the system was empty the real fun could begin... The challenge was to get 90 gallons of antifreeze out of two drums upwards - without a powered pump! By utilising anything that would lift a drum we managed to start trickling from the first drum into an inspection cover on one of the radiator tanks.

This method soon proved to be extremely slow, so we tried a hand pump on the other drum at the same time. Despite the small size of the pump, more suited to dispensing the odd gallon or so, it was much faster than gravity alone. We took turns to hand pump until both drums were empty. With the tanks back together we connected a hose from the mains water to the loco filling point. When the system was full the triple pump was run for a few minutes to mix the antifreeze and water to about 50% solution.

During the rest of December the bodywork continued apace, including transforming the cabs, rubbing down, undercoating and grey gloss. and I managed to flatten the batteries.




© 2005 71A Locomotive Group