LOCOMOTIVE ENGINEER'S REPORTS
In April 2022 Sir Nigel Gresley returned from an overhaul which took more than six years and cost about £800,000 plus about £100,000 for the support coach. If you would like to make a donation towards the cost of this overhaul please click on the donate button.
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| From Jan 2025 | ||||
| Overhaul Reports 2015-2022 | Return to Home Page | |||
From January 2025.
10 April 2025.
The safety valve exam continued with the return of components to Crewe. The valves and seats were taken and skimmed in the lathe over the previous weekend. At the back of the boiler shop the safety valves were measured and reassembled.
Touching up the paintwork in the cab continued.
The new pads to raise the leading intermediate grate bearer were welded on. The bearer was then refitted, and the grate refitted. The grate now lines up well with the trailing side of the drop grate.
After the filling and sanding the left buffer fairing was completed, it was finished to black gloss by the LNWRh paint shop.
As part of the lubrication exam, the little end oil boxes were cleaned out, then the little end restrictors and pin trimmings were gauged. All are within specification. With the gauging of the little end lubrication completed, the covers were refitted.
The repaired cab middle left ventilator cover was refitted. The new handle was then fitted and painted.
Meanwhile LNWRh started to refit the boiler plugs and doors. As planned we did a water volume test on the boiler. The fusible plug holes in the firebox roof were fitted with connectors to which we could fasten a long length of clear plastic hose. We then measured the water put in the boiler at different heights, such as the position of the leading/highest fusible plug, bottom and top of the water gauge frames.
With the water volume and height tests completed the boiler was drained down sufficiently to allow the fitting of the fusible plugs. Meanwhile LNWRh started to make new gauge frame plugs as the old ones were condemned as too loose.
It has been noted during operation that coal gets behind the M8 brake stand and it has been planned for a while to make a new cover to close the gap between the M8 stand and the backhead. This has now been fabricated and fitted.
With the safety valves reassembled they were refitted to the loco by LNWRh. The trailing valve is set to operate at a slightly higher pressure than the leading to ensure the leading blows first. As the leading valve does all the work this wears, so it was decided to swap their positions. The trailing was put in to the leading position, but the leading wouldn't go in to the trailing position. So, the valve was taken to the bench and its stud holes enlarged. The valve was then fitted.
As the steam test was upcoming it was decided to refit the old gauge frame plugs as we were still waiting for the new plugs from the machine shop.
As we still had access to the cab roof the manifold isolation valve was operated from the cab hand wheel, and the universal joint oiled and packing nut nipped.
The modified safety valve cab roof cover clamps were put in place so that when the valves were set the cover could go straight on. The boiler was then refilled and a warming fire put in for testing the safety valves next day.
With the boiler warming through the left side motion buttons were examined.
Next day the fire was built up and steam raised for setting the safety valves. The valves were set by LNWRh. We were pleased with the pressure drop on the leading valve, an improvement on last year.
With steam we ran up the air pump and tested the air system. We then filled the boiler and left a warming fire in for tomorrows steam insurance exam. When shutting the manifold valves we found the blower isolation stuck open. This would have to be attended to later and is similar to late last year when the valve stuck shut.
Next day with steam being raised for the insurance exam we attended to some other jobs. A cover was made for where an electrical conduit cuts through the plate in front of the smokebox. The hole allows ash in to the frames and the cover will prevent this. A matching plate was also made to cover a cut out on the opposite frame.
Inside the frames a new bracket made and fitted to support the middle cylinder lubrication pipe.
The steam test was also used for the annual LNWRh exam. It was noted that there wasn't a label on the lamp cupboard stating "Emergency Equipment". Apparently a requirement, so a temporary label was made up.
An adjustment to the air pump governor was also required to slightly lift the cut-out pressure. This then required the air system safety valve to be adjusted. Both very tricky to do.
When testing the sanding gear it was found that the left gravity sands wouldn't feed so it was rodded. This didn't clear it so we removed the sand pipe and cleared it. The sands not being used since last year had gotten a little damp. When reassembled it was seen that the left passed a small trickle of sand. This was due to the sand valve in that box not fully closing so the cable in the cab was adjusted to close it tightly.
The steam test for the insurance inspector went well, with no concerns.
Fortunately the new snifter worked fine, sealing against boiler pressure and dropping easily.
The front right corner of the foundation ring cladding has seen some corrosion so it was wire brushed and painted.
With steam testing completed the boiler blisters were refitted.
Next day the fire was built up again for the electrical tests. It was found that the steam chest pressure sensor wasn't working correctly so a new unit was fitted. The old when removed appeared to be clogged, but it was decided to fit a new unit.
The timing of the TPWS air brake demand was also found to be out side of spec of 12 - 14 seconds. This is governed by venting through a fixed restrictor in the brake application unit. To access this the driver's cab floor had to be removed. On the BAU a bulky solenoid valve covers the restrictor we needed to examine, but due to the BAU being in a tight space surrounded by pipework it was impossible to get the restrictor out, even though we made a special tool. Finally we removed pipes, floor structure and managed to get the BAU out and on to the bench.
On the bench the restrictor had to be drilled out as it was stuck. Fortunately LNWRh had a spare restrictor so that was fitted. The solenoid valve, unnecessary for a steam loco was left off and a cover plate fitted. The cover plate is a standard replacement for the solenoid valve and LNWRh had these in stock. This gains us a lot of room where the BAU is mounted.
The BAU was then refitted and after a few adjustments we were within spec. Time was tight as we had to sort this problem while we had access to the OTMR download reader in the LNWRh office, as the timings are taken from the OTMR recordings.
In front of the smokebox the new ash covers were finished by drilling and tapping the frames. The covers were painted and fitted.
The safety valve cab roof cover and safety valve shrouds were refitted.
Next day, back in the office the modification to the BAU was written up for approval of the CME. After approval it was forwarded to LNWRh.
On the middle cylinder oil pipe fitted with a new clip last week, there was a propriety plastic clamp that had been affected by heat, so a metal clamp was made to suit and later taken to Crewe and fitted.
New main power supply batteries were fitted in the tender.
With the steam test complete it was decided to replace the gauge frame plugs. The gauge frames are old and the plugs have to be made for each individual hole. The plugs were made by LNWRh. While fitting the top plugs it was found that they were fouling the internal restrictors that limit the steam flow in the advent of a broken glass. The left was freed by adding a chamfer to the internal hole in the plug, the right required the top of the restrictor reducing in height.
The blower manifold isolation valve had again jammed, this time when fully open, so the top of the valve was removed and operated in the vice. The valve operated easily after cleaning and lubricating, so was refitted.
Next day was fire lighting for our move to Grosmont. The grate and firebox were cleaned. The right intermediate outer (double) firebar had "fell in" between the grate supports. So, a notch was cut in its leading edge to stop it working forward which allowed the trailing end to fall off the trailing support.
After welding the horn crack the electrics were reconnected. Meanwhile the loco was cleaned.
Upon inspection it was noticed the ashpan had deformed and prevented the damper from fully closing. So, the bottom of the damper was ground back allowing it to close tighter.
The Assist Failed Train and AWS isolation valves were fitted with security tags as required for the mainline. The old tags were removed when we were working on the BAU.
When we adjusted the gravity sands earlier, I had taken a photo. When I later looked at the photo, I noticed there was a locking screw missing from the adjustment. A new screw was fitted.
After the grate was cleaned, and the smokebox primary screens were refitted, a fire was put in. Next day was our prep and FTR day.
The atomisers were examined. There was good steam and oil flow from all the outlets.
The repainted cab doors were returned to the loco and fitted.
During FTR it was noticed that the reservoir pipe pressure rose to the main reservoir pressure, whereas it should stop at about 100psi. This has happened before and pointed at the FVF2 valve beneath the cab floor. With no time to loose we removed the cab floor, cleaned round the valve and removed its top. Inside was a lump of rock hard sealant. This was removed and the valve reassembled. The air system was then checked again, and it repeated the fault. So we cleaned under the valve, where there is a vent, and removed the top of the valve again. There was nothing obvious but a small spec on a sealing O ring, so this was cleaned off and the valve reassembled. This time the reservoir pipe pressure stopped rising and operated correctly.
Meanwhile the loco lubrication and cleaning was completed.
Next day we have a pleasant and thankfully uneventful trip to Grosmont with plenty of people out to see us.
At Grosmont we went straight to shed and the boiler was slowly filled.
Next day we went back to Crewe, after the loco exam was completed by NYMR and SNG. This was to return support crew to their origin, but also to collect some spares. While at Crewe the complete duty engineer paperwork for the Grosmont move was submitted to the LNWRh Engineering Office.
At Grosmont the chimney cover was put on and the loco checked over. The support coach was connected to power after it had been shunted.
Back in the office, electronic copies of our certification was sent to the NYMR.
We were soon back on the loco to prepare it for NYMR running. A water change was carried out. The firebox and grate were cleaned then a warming fire put in.
The small ejector cap, that fizzes from time to time was removed and the sealing faces lapped.
It had been reported that there was a weep at times from the steam chest pressure gauge connection, so the gauge and snubber were removed. The snubber was cleared of deposits and the union, snubber and gauge joints were remade with new copper washers.
As we weren't over a pit we could only examine and prepare the outside axleboxes.
The loco was given a good clean over a couple of days.
The tender footstep blocks, mandatory for the network were removed.
Next day was our first NYMR running day and the loco looked superb. We did all the prep though left the cab oiling to the driver and the fire to the fireman when they arrived. The loco ran with no issues though we have a blow to the left piston packings, so situation normal when on a preserved railway.
On the second day the loco stuck in the Pickering head shunt. The SNG rep went under and backed off the brakes. Strange as the loco brakes are adjusted daily, always using the same procedure and it didn't happen on the first day or since.
Also on the second day it was noticed that there was a crack in one of the leaves in the right leading tender spring. We normally break a spring or 2 while on preserved railways. It was OK to run and keep under observation though plans were put in place to replace the spring during our day off between the two four day running periods.
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11 March 2025.
We attended the launch of the Greatest Gathering at Derby Litchurch Lane works at the end of January. To do this we had to break our winter maintenance to travel from Crewe. Work started as usual on fire-lighting day, two days before our trip. The grate was examined and a number of firebars changed. As our new castings were not available we used some of the fabricated mentioned in the last report. Outside the loco was cleaned and oiled.
Also during prep the left piston rod was cleaned up. It looked a little bronzey so was polished. It looks like the rod is picking up deposits of the bronze piston packings, though the rod is well lubricated and hasn't been found dry at any time.
The LNWRh FTR found some of the screws in the ends of the tender springs loose. This is a pretty routine find, and they were tightened. These screws, mentioned before in reports, locate the ends of the springs in the spring hangers. They are exposed to fluctuating forces and wear and come loose. It's down to the original design.
The cab doors were also refitted after repainting off the loco.
Next day was the FTR day proper, and the loco was taken round Crewe for turning. With the remaining time the loco was polished and finished to our usual exhibition finish.
Next day we ran to Derby and the loco was very well received. It took a starring role with all the dignitaries wanting to go on the footplate. SNG was positioned first and everything else around positioned to suit.
The loco carried the SNGLT headboard for the first time in 2024, after it received a touch up.
Later that day we returned to Crewe and the loco boiler filled and the engine made safe.
Next day the oil levels were taken and recorded. The brightwork was protected with oil or vasaline.
After the weekend we returned to Crewe and restarted our winter maintenance with a paintwork freshen-up with touching up and filling the casing behind the left buffer.
We disposed of last weeks fire. We also prepared the firebox for the forthcoming cold insurance exam. The firebox roof stays were cleaned, arch swept off and grate cleaned. Finally the ashpan was washed out. After disposing of the fire the loco was shunted across the depot in to the mechanical workshop so that scaffold could be put up to allow access to the snifter, anti-vacuum valve, behind the chimney. While waiting we removed the hopper door which was found difficult to close after its recent repair.
The hopper door was taken off and the hinge holes in the ashpan lengthened to allow the hinges to be lowered slightly, lifting the front edge of the hoper door and allowing a better fit. Two of the 3 loops that locate the locking pin on the outside of the door were cut off and new loops welded on to allow the pin to go across the bottom of the ashpan and locate the bracket on the far side. Finally the pin was dressed on its end where it entered the bracket and all was refitted. It is still tighter that it used to be but can be closed without tools or extra manpower so shouldn't delay operation.
Meanwhile touching up paintwork continued with various jobs in and under the cab. While under the loco round the injectors was cleaned as they are a real trap for dirt. The bolting of the injectors were also checked as they have been found to work loose in the past.
At last the scaffold was available so we could get to the chimney. First the whistle was removed and then the chimney cowl could be released and moved forward on to the upper cods mouth door. The top of the snifter was then removed and the studs and faces cleaned. One stud was damaged so this was replaced, using a bolt as a start. The bolt head cut off and the top then threaded. The snifter top was fitted with a copper joint but this was discarded and a more reliable reinforced graphite gasket used, made using the copper one as a template.
When examining the old valve, the lower spigot had broken off. Looking at the drawing the guide bush for the spigot should be radiused to suit the radius of the valve where the spigot joins the main valve. The new valve has this radius. However, the bush pressed in to the body of the valve housing does not have this radius. To prevent the possibility of the new valve having its spigot cut off, the guide bush needed the radius, so this was cut in-situ using the new valve as a gauge. Eventually when blued there was good contact, and finally the valve was ground in to the bush.
The upper spigot in the valve body top was measured and the snifter valve bored to suit, a machining allowance was left on the valve on for final fitting. The whole valve was reassembled and the travel of the snifter measured. The valve was also manually lifted and it was free to rotate and drop, showing good concentricity of the parts.
With the snifter back together the chimney cowl was refitted and the polished whistle refitted. The whistle lock was refitted with a new split pin.
Meanwhile out the back of the depot our springs in the open air spring rack were given a coat of paint to protect them from the weather.
In preparation for our boiler inspection the smokebox primary spark screens were removed. The boiler blisters that cover the mud doors were also removed and stored in our support coach workshop. The boiler was then drained.
The large ejector cap, that fizzes from time to time was removed and lapped in and refitted.
The annual lubrication exam was started by removing the bogie oil trays, allowing examination of the oiling pads and bogie journals. While out the tray lids were refurbished so they indent in the closed and open positions. A combination of repairing the shape of the lids, indents and springs, and filling and re-drilling the lid pivot holes got all the lids working positively for the first time in my memory. We'd long thought that we should restore the original arrangement of leather seals to the lids, so enthused by the now refurbished lids, we set about sourcing leather sheet, and copper rivets that are used to fasten the leather to the lids.
The safety valve cover and shrouds were removed to access the safety valves, which are examined annually. The safety valve securing nuts were then removed with a special tool fabricated for the job. The safety valves are in pockets so a standard spanner or socket can't really get a good amount of torque. The safety valves were then removed and taken to the dedicated bench at the back of the boilershop where they were stripped down and the parts cleaned and examined.
Back at the engine the boiler doors and plugs were removed. Meanwhile the casing behind the left buffer received another round of filling and sanding.
Up on the top of the loco the safety valve pads were cleaned and studs die-nutted. Then the studs for securing the safety valve cover were cut off as they were wasted and it has been long planned to replace them. With the studs cut off their centres were marked and then drilled through. They were then tapped out to accept screws. The 2 leading holes had seen a previous repair and the holes were enlarged but took a helicoil tap, so helicoils were bought and fitted.
The safety valve cover is clamped down with small plates. The original design was for shaped plates so the studs have a straight pull, but we have flat plates, so to get a straight pull pieces of steel have been welded on the plates, opposite the clamping side.
To get the cab mud door out, a hook is used with a threaded end that fits in to the door stud to hold it. In the cab we had to make a short version as the ones at Crewe are too long. The tool now lives in our "special tools" drawer of our toolbox.
The removed mud doors were cleaned with a wire wheel. Some needed a little dressing with a file to remove the odd bump. The door threaded studs were die nutted and the end holes cleaned out with a tap.
The boiler plugs were removed, then cleaned on the wire wheel.
We were given a form to fill in by LNWRh to record measurements taken from the safety valves. It was agreed that we should produce a CAD version and that we would share it with them. That has been done and we used it to record our safety valve dimensions.
The loco was then shunted outside for washout and we gave assistance to the LNWRh boiler smiths.
For the lubrication exam, an existing defect is the poor fit of the some of the mechanical lubricator drain plugs. So new plugs were purchased then drilled through for locking wire before fitting. The mechanical lubricators are drained to remove any water and it was planned to take the opportunity to fit new plugs.
The tender oil trays were then removed and were cleaned out, and the oiling pads and journals examined. The Cartazzi axlebox top oil boxes and trimmings were also cleaned and examined.
While we had access to the cab roof, the left middle cab roof ventilator cover was removed for repair. Sometime ago the handle had broken of so the cover couldn't be opened.
Still helping with the washout we took the water gauge frames apart and took the opportunity to lap the sealing faces on the gauge frame bodies.
Both axlebox and cylinder mechanical lubricators were drained. The axlebox lubricator plugs were OK for reuse but new plugs were fitted to the cylinder lubricator. The drain plugs were then wire locked, while the gauze filters were cleaned.
The insurance cold exam was carried out and the boiler inspector was very complimentary about the condition of the boiler, remarking on the wonderful condition of the inside surfaces. We have put a considerable amount of work in to this and it has been extremely worthwhile.
Under the loco the leading and trailing coupled oil trays were removed for inspection. The dust seal on the trailing right had deformed and was now too short to go right around the journal. We had this sometime ago with the leading set, so it was dealt with in the same way. A new section of larger section packing rope was obtained form LNWRh and packed in to the holding clamps.
The Cartazzi oil trays and journals were inspected.
The left middle ventilator cover was drilled through where the old handle had broken off. It was then tapped through and a nut welded on the outside to give greater thread engagement. As there's a mesh over the ventilator the nut was ground down and rounded so it wouldn't foul the mesh. A handle was then made in the style of the old one, but a little more robust. The cover was then repainted and refitted. The new handle was then fitted and locked in pace with a lock nut on the inside of the cover.
The safety valve exam continued and the springs were blasted clean.
The grate was again removed to exam why the grate was now lower than the back of the drop grate. With the grate out it could be seen that the grate bearer had sagged in the middle, probably due to the heat that has been burning the firebars and damaging the ashpan. It also appears that the drop grate shaft has also moved which adds to the offset. So it was decided to remove the bearer and add packing pieces to raise it to the height of the drop grate and remove the step.
After pinching the loco to get the middle big end horizontal the end covers were removed from the driving coupled oil trays. Having the big end out of the way is a big help. Last exam we also removed the oiler pads, but it is difficult to do and could lead to damaging the pads, so this year we agreed with LNWRh to just remove the end covers. After examination the covers, compete with their leather gaskets were refitted on the numerous small studs, all cottered. Finally the dust sealing ropes were pulled tight and secured.
The fit of the trailing vacuum cylinder lever safety loop was questioned during the annual LNWRh mechanical exam. The loop is fastened to a frame stretcher and looks like it is not fully up. This is due to the lower nuts that are welded on and the weld holds the nuts off. So the loop was removed and the weld filed back and the loop now fits up with the nuts against the stretcher.
With the oil trays and journals examined we moved on to the oil pots and trimmings, starting with the middle slidebar oil pot and the oil pots on the leading intermediate tender axlebox top slides. The tender trimmings didn't look too good so we made new ones.
The fusible plugs were removed and left in the boilershop for examination.
The whistle valve has been seen to pass so it was taken apart for examination. The valve was found marked. The valve seals on a stainless steel seat which also looked to be marked. The valve was skimmed to restore its surface and our slacker lapping guide used to clean up the valve seat. Fortunately the seat just has a deposit on it and it cleaned up really quickly. The valve cap was lapped to the body then the valve reassembled.
In the cab the wear to the edges of the OTMR and TPWS enclosures was repainted.
The lubrication exam was continued with the right motion buttons. The drop link trimming was replaced.
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12 February 2025.
With the cab pressure gauges away for their routine annual calibration, the opportunity was taken to fit a new dial to the steam heat gauge. The red line was marked at 60 psi, however, when Crewe fitted a steam heat safety valve that was set at 50 psi, so it often lifts unnoticed in the cab. Hopefully with the red line at 50 firemen will keep the pressure down. The gauge artwork was altered and sent through to the calibration lab to produce and fit the new dial during recalibration.
The purchase order for our new supply of firebars was firmed up early in the new year with our chosen foundry. The patterns were then sorted and taken to the foundry and we also carried out a supplier assessment as we haven't used this foundry before.
Back at Crewe we were straight in to our winter maintenance with the dismantling of the smokebox to access the blastpipe, caps and Kylchaps for de-carboning. The screen basket around the chimney was the first thing to be removed.
At the other end of the boiler we started our grate and ashpan repairs. As mentioned in previous reports we, as other locos, have suffered heat damage from the coal we have been using late last year. The drop grate shaft covers inside the ashpan are very wasted so these were removed for repair. To do this the drop grate operating linkage was removed from the right end of the drop grate shaft. The drop grate shaft end brackets were then released from the foundation ring, after the drop grate was packed up on blocks inside the ashpan to take its weight.
The hopper door previously removed had its inner cover plate removed by grinding the nuts from the bolts that fasten through spacers in to the outer door plate. The removed wasted and deformed cover plate was measured up so a new plate could be made. The old spacers were also wasted so were scrapped. The door was then sand blasted.
The overhauled front bufferbeam steam heat cock was returned from the CME's workshop and mounted back on the loco. It now operates smoothly.
The cover plates on the coupled axleboxes were examined for tightness as a loose screw was found on the right leading axlebox. The cover screws were tightened as required and some were changed for new screws. Some longer screws have also now been purchased so that if we need to change any loose ones in the future we have them this option in stock.
Back in the firebox the drop grate was released by burning off the bolts that fasten it to the drop grate shaft. We had to remove one of the studs from the left foundation ring to get the shaft end bracket off. Luckily it came out relatively easily after heating and allowing it to cool. With the left end bracket off, the shaft could be moved out of the right bracket and the right cover removed. Some of the cover bolts had to have their nuts burned off. With that cover out, the shaft could be moved to the right and the left cover removed.
The covers were then needle gunned and given to LNWRh for welding in new pipe sections.
An inspection of the right piston and cylinder was due this winter. This is the cylinder closest to wear limits. We measured all cylinders last year during the P&V and it was decided to come back this winter and see how the right was getting on. The piston and bore were measured and no significant additional wear was found so we reassembled the cylinder.
In the smokebox the last of the spark screens were removed which allowed access to remove the Kylchap cowls. One centralising vane was taken from each chimney and the bottom mounting nuts for the cowls were removed, which allowed the cowls to be lifted and removed.
With the cowls out of the way the blower ring was then removed. The blower is mounted on short stands that also secure the blastpipe caps. The stands were taken out with the blower ring. The stands were secured with stainless nuts, which seemed a good idea at the time due to the corrosive nature of the smokebox, but removing them was difficult as they wouldn't burn. A couple of nuts had to be chiselled off.
In the cab, the blower isolation valve at the manifold had its bonnet and spindle removed. On our last trip of 2024 this valve had become very, very tight. Before the valve was opened the manifold shut off valve was closed. This is rarely operated and was tight but operated OK. With the blower valve on the bench it could be seen there had been some binding of the valve threads, perhaps due to contamination. The assembly was taken apart, cleaned and dressed.
The damper door and screen had been previously removed. This was inspected by the CME and it was decided to renew the damper screen mesh as it had burnt through in one spot and was deformed. The screen frame is partially bolted and otherwise welded. The present screen is made from expanded metal mesh. LNWRh have some quite heavy steel wire mesh which they use on their locos so we decided to give that a go. It was calculated that the new mesh increases considerably the free air area of the damper.
The drop grate covers were returned to us, tacked up for trying in. They were tried in on temporary bolting and they seemed OK so were returned to LNWRh for final welding. They were then finished by SNG, putting an angled cut on the end of the tube sections to reduce the chance of ash settling in or passing through the covers.
On the foundation ring the drop grate bracket studs were die-nutted and we managed to recover the stud removed by heating, saving us making a new one.
In the smokebox the lower spark tray was released and removed, allowing us to remove the blastpipe caps. The Kylchap cowls were de-carboned, a time consuming process.
Examining the drop grate it was noticed that the leading, double firebar was cracked through one of it's webs so would require replacement. So the mounting nuts were burnt off and the firebar removed and scrapped.
The damper screen had the bolts holding the inner and outer frames together, removed, then the screen frame was cut where welded to get the old mesh out.
Another thing attended to was the firehole flap. This had started to crack along its bottom edge. The cracks were ground out and the rough weld repair on the back ground down. The flap was then given to LNWRh, who welded up the cracks. The flap was then refitted by SNG.
The blower ring was cleaned of scale and the mounting stands removed. The blower ring didn't look too good when the scale was removed so it was decided to refer it to the CME for examination.
The drop grate covers were finally refitted and held with temporary fasteners while new permanent screws were ordered. With the covers back in place the shaft was refitted into the end brackets and the brackets bolted up on to the foundation ring. The covers are longer than before repair providing additional material for wastage. The new dimensions were recorded so we can modify our drawing for future reference.
While retrieving our only spare double drop grate firebar it was decided to bring all the spare drop grate firebars to the workshop. The existing drop grate firebars are deformed and were due for renewal for the 2025 season so it was decided to renew now. We didn't have enough to completely replace all the old ones so two of the best old ones were retained. A couple of the new spares had to have the bolt holes enlarged to take the bolting. The firebars are bolted to side plates, that are then bolted to the drop grate shaft.
While at our Crewe storage container the spare snifting valve castings were retrieved, as part of winter maintenance we need to examine the snifter as it hasn't been dropping satisfactorily suggesting a possible issue.
Away from Crewe in a volunteer workshop a lapping jig was made for the blower valve. Back at Crewe the jig was then used and the valve seat and valve lapped. The valve seat and valve were in good condition so it didn't take too much. The valve body and bonnet were then lightly lapped and the valve reassembled.
The drop grate now reassembled, including the operating linkage, was test operated and left in the raised position so that we could access the ashpan for the refitting of the hopper door and damper. The new permanent bolting for the drop grate covers was fitted while positioning the covers to be concentric to the drop grate shaft.
Next to the loco work continued on cleaning and decarboning smokebox components ready for reassembly.
Two gusset plates were made for the damper screen frame to strengthen the upper corners. Sometime was spent on straightening the frame. With the new mesh in, the inner and outer frames were tacked welded together.
The cab received a freshen up from the paint brush. Some of the red handles, including the handbrake, on the tender front were painted blue and white. This was provoked by an BR (E) memo from the 1950s that stated water scoop handles were to be painted red to distinguish them from handbrakes. Therefore, handbrakes were not painted red, as our was. The front of the tender, the coal gate and door, and shovel plate were also touched up. The M8 cover has also received its annual fill and paint, though receives a chip every few shovel swings. The cab doors were taken by to the LNWRh paintshop for repainting.
With the smokebox emptied the vertical air pump exhaust pipe was removed and joints remade. Every few FTRs we get a report of wetness on the lower joint. It's relatively harmless and might be from some other cause, but to rule it out the joints have been remade. With access easier we were able to get a flogger on the unions so we know they are well tight.
With rivet nuts now fitted, the lower right firebox boiler band cover was refitted. The band under the cover had already been painted. With the cover on the new screws were painted.
Before refitting the Kylchap cowls the adjusting and securing nuts needed loosening off. We tried heat but in the end it was easier to burn them off and use new nuts. After burning the old nuts off the threads they were die nutted to clean them up.
Meanwhile the underneath of the loco received a good clean. Particular attention being paid to the intermediate hoses and conduits, under the cab ready for annual exam.
In the smokebox the blastpipe casting was de-carboned. A special tool was made to get in around corners. The carbon build up is mainly at the top of the blastpipe tapering off, down the inside of the casting.
Taking advantage of the space in the smokebox, the middle steam chest oil pipe was removed and given 2 wraps of insulation. It was then refitted with two2 new clips to take up the increased diameter and painted with high temperature paint to seal the insulation.
The damper screen was taken to the welding bench and welded all round. Next day the damper and screen were refitted.
The coach fridge required securing, identified in an LSL safety audit, so a strip of wood was sourced and fastened to the fridge cabinet, preventing the fridge from working its way out when the coach is moving.
In the smokebox the cleaned blast pipe nozzles were refitted with the blower ring stands, and the lower spark tray.
The coach wheelsets at contractors have had their old tyres removed and wheels skimmed. At the time of writing the new tyres are being fitting.
Back at Crewe the removed blower ring was examined and condemned by the CME. We have a spare and this was tried in place. It needed some heat to slightly reshape it so that it fitted on to its stands. Finally, with a new gasket the blower pipe was connected.
The cab doors returned from the paint shop and were put to one side for refitting for our trip to Derby.
The new cover plate for the hopper door was drilled for it's mounting bolts and shaped to fit.
We needed to fit the grate to enable us to go to the Greatest Gathering launch at Derby Litchurch Lane, and as we have run out of some spares we fabricated some long firebars. Some other spare firebars were fitted but most of the grate was made up of recovered bars.
Before fitting the firebars the carrier behind the drop grate was fitted. The ashpan sprinkler pipe is pinned to the carrier and this was reassembled using new split pins. The ones used were slightly smaller than those removed to aid removal next time.
In the smokebox, reassembly continued with the Kylchap cowls being fitted. The spark arrestor was refitted but some difficulty was experienced which required the removal of 3 of the 4 primary screen plates for access. The blower pipe has moved slightly due to the new blower ring requiring the alteration of the spark arrestor closing plates.
The middle piston packings were examined. They were found to be in good condition with no concerns raised. The piston rod was cleaned and checked before being oiled and reassembled.
The gauge frame drains, end below the cab but are higher than some of the horizontal pipework. The right in particular can drip on to pipe work and this has led to corrosion so it was decided to lengthen the drains. Two extension pieces were made and the ends swaged to fit over the existing pipes. These were soldered on. A clip was made to secure the left pipe.
Our cab pressure gauges were collected from the calibration lab. The gauges were then refitted and the LNWRh Engineering Information Pack updated with the new calibration certificates.
The hopper door retuned form the boilershop and was refitted. Some adjustments and grinding was necessary to fit. The locking pin was found to be very stiff to enter and rotate to lock. This will require further work when we return from Derby.
The tender corridor door latch was refitted after refurbishment, and painted on the door.
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