OVERHAUL 2015 - 2022
Notes from information supplied by Darrin Crone, Locomotive Engineer.
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From January 2022.
23 January 2022
The new toilet tank (CET) was tried on the coach and it was found that it fouled the brake pull rod to the passenger end bogie. The tank was then packed off the coach to clear the rod and shunted through some tight curves to ensure that it would be clear under all circumstances when in traffic. New spacers have been designed to locate the tank in its new position and these are now being fabricated. The new toilet bowl and the tank's outer insulation have now been delivered.
The coach guards compartment ceiling has now been repaired by the coach overhauler and we have asked for quotations for floor covering for the corridor and other areas currently as bare boards.
At Crewe the lapping of the lens rings was completed. The middle steam pipe assembly was fitted during the last report, the next to be fitted was the left followed by the right.
The atomised oil nozzles have been fitted to the 3 cast iron cylinder top steam pipes and connected to the atomiser oil pipework. All nozzles were cleaned and the threads refurbished and are now sealed in to their pipes.
Also on the right CI steam pipe the steam chest pressure gauge shut off valve has been refitted. Not happy with the sealing of the valve a spacer was made and new copper washers fitted. There was an ongoing issue with the fouling of the oil box lid on the pipe from the shut off valve the oil box bracket mounting holeshave been slotted and the box moved, now the lid is well clear.
With the steam pipes in place the smokebox sealing plates were fitted. Refectory rope was then packed between the plates to provide a gas tight seal, the plates on the inner left requiring adjustment on a hydraulic press to get a close fit on the smokebox wrapper.
The blastpipe casting has now been refitted. The blastpipe casting was turned over to examine the bottom face and to remove the last of the carbon deposits. The face is good as the casting is relatively new. The face on the middle cylinder is in fair condition but does run out to the outer edge so it was decided to fit a gasket to the face to prevent corrosion where the gap between the castings increases and in to the mounting studs, as well as ensuring a good gas tight seal.
The plate in front of the chimney, with the whistle stand was also refitted, being sealed in with webbing. The smokebox front plate was then similarly fitted and the chimney put in position ready for its alignment to be checked.
The chimney fabrication has seen further descaling. The guide vanes for the Kylchap cowls were removed and will require replacement. The threaded holes for the spark screen top that fixes to the bottom of the chimney have also been cleaned out.
With the left and right steam pipes fitted the outer superheater header covers were refitted using new countersunk screws and a webbing joint to ensure the smokebox vacuum is maintained.
The new snifter doubling plates have now been fitted. This should improve clamping of the seal around the valve body.
When the assembly of the smokebox is completed a new pipe will be fitted from the atomiser/whistle valve, along the top of the nameplate. The forming of this pipe has started.
The smokebox blower pipe to blower ring joint has been refurbished and a new joint made ready for fitting.
Good progress has been made with the cab injector pipes to the boiler mounted clackboxes. These needed the ends re-flaring to take new air ministry joint cones. New flaring tools were made by an Engineering Team volunteer as our loaned tooling was short of one size we needed. We eventually made two sets so that we have our own for the sizes we need. The pipes have now been flared using our new formers and the cones will now be machined to size.
The tender corridor floor and back of the vestibule door has received paint with the first coats of black top coat going on to the floor.
The tender number plate has now been secured by brass screws replacing the temporary screws used at York.
A new water scoop instruction plate and a 5000 Gallon plate, missing from our tender have been very kindly donated. Our donor painted them, with our paint, so they are ready for fitting.
The new driver's side builder's plate has been fitted with bronze captive screws and repainted.
Under the tender the filter box and sump on the bottom of the tender tank has been removed in preparation for the blasting and coating of the inside of the tank.
The loco nameplates have had their backgrounds painted red, in keeping with the wartime black livery.
Under the loco and tender have both seem further painting.
It was planned to hydraulic pressure test the boiler for the insurance company first week January. In the last report the boiler was filled with water, this was left over the Christmas break to warm to workshop ambient. The boiler was pressurised by LNWR(h) but the regulator stuffing box leaked quite badly so the exam was stopped. A new seal has now been put in, though this is no 5 minute job with a couple of the manifold pipes having to be removed and the regulator cross shaft. The cross shaft only being removeable with the regulator valve being slightly open. For the hydraulic the regulator was clamped closed so the dome had to come off and the regulator valve released. A new gasket was made and fitted to the stuffing box, and the regulator re-clamped and dome refitted.
During the test hydraulic it was noticed that there was a small run of water from the brake ejector steam shut off valve on the manifold so this was removed and a new seal put in.
The opportunity was also taken to adjust the position of the steam sands isolation valve to give additional clearance from the cab roof and to make it easier to get to from the drivers position.
We then pressurised the boiler to in excess of boiler pressure and both new seals held tight, but the firebox tubeplate leaked. It was decided by LNWR(h) that some caulking should be done on the joint and this is now completed.
During this high pressure test a leak the atomiser front tubeplate stub pipe joints was found to leak at the tubeplate. This joint has now been remade. The connection being behind the superheater elements and is very awkward to get to. The face on the pipe was refurbished at York but the tubeplate face could do with attention. Unfortunately this was overlooked during the boiler overhaul.
It is not unusual for water leaks during the hydraulic test, as the boiler is designed to operate hot, the LNWR(h) boilersmiths are not concerned with progress so far. Delays so far have been mainly down to the availability of boiler inspectors. At this time of year it is normal for locomotives to be going through their tests in preparation for the coming running season, coming out of winter maintenance so the boiler inspectors are busy and it can be a challenge getting their time. We were prepared for a second attempt at the hydraulic last week but the inspector didn't have time for us.
The safety valves require inspection by a LNWR(h) boilersmith before use, so they were stripped and components laid out. They were inspected and have now been reassembled ready for refitting.
The cladding was left off around the sides of the foundation ring for inspection during the hydraulic test but these areas will require insulation and cladding before running. The old cladding is in very poor condition so will be renewed. To support the cladding new brackets are being made and fitted.
The Bowden cables to the drain cocks and gravity sands have seen some attention. The gravity sands were set up and appear to operate satisfactorily, but we need sand in the boxes for final set up.
The draincock Bowdens are a different issue and were very stiff so the levers and rods that link all the drain cocks were dismantled and their fit improved. Thus got the arrangement working freely, but the cables are still stiff. We have found that removing some of the grease from the Bowden conduit does make the cables a little freer. This work, frustratingly, continues.
One of the right cab windows was put in the wrong way round at York. Did you notice? This has now been corrected and shims have been sized to allow the windows to slide freely.
With the lens ring lapping complete we have moved on to the fitting of the middle big end bearing key. The key was made from new material initially machined then fitted by hand into the rod. The bearing machined by one of our volunteers was returned to Crewe and then fitted into the rod, and the key fitted in to the bearing. During fitting it was noticed that the end faces of the rod and strap were not exactly flat to each other, not surprising after decades of being pulled up under considerable force, so a slight taper has been ground on to the spacing prices, called gluts, to accommodate the slight runout on the strap and rod. The final assembly was flogged up and is now ready for final machining of the bearing surface in the rod. We have decided to do this at Crewe on their borer.
The period under review saw a return to bodywork preparing the cladding for a touch-up paint job ready for members day and running in. The smokebox number plate and shed plate have been removed and the holes filled as these were post-WW2 additions.
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