Sunday 23 October 2016

Maintenance Update (bung, spray, flawed, exam)

Thursday 20th
The tube arrived …
Bruce had asked: How’s it getting here?’ “Not on his car’s roof rack”, said I … but guess what?
I wish I’d had my camera with me !!!
Update from Brian: “Had a call from NYMR, Loco is being picked up this morning could not give an ETA for GWSR.”

Friday 21st
Loco arrived at Toddington at 07.10 (according to Alex). Bruce & I arrived at 09.30. It was a misty day - couldn’t see the hills. Note the empty car park!

We got ourselves ready, and then Carpo and Bruce tested the theory of getting “Skinny” (the new tube) under the regulator header, through the tube plate, and along the barrel without meeting something on the way.

There’s just about enough flexibility in Skinny to be able to pull it down at the firebox end.

But it does look as though a small amount will have to be ground off the bottom of the regulator header, or possibly a deliberate bend in Skinny to get it to slip between the obstacles?

Before Carpo shunted 2807 into the yard, I noticed what seems to be a shim out of place. This is under the top RHS slide bar. It is not obvious what has happened here. Why has it slid out, and why is it bent downwards?

Carpo took a sample of boiler water for analysis. Bruce & I tackled the smokebox. We removed the spark arrester, and then we could see the full layout within 2807. It looks as though Skinny will pass below the petticoat OK, though at least one of the superheater elements will have to come out to make space.

You can (just) see the bung in the end of the errant tube. Before attempting to remove the bung, Bruce & Carpo demolished the brick arch. Ironic, quoth Carpo, as the arch had survived NYMR perfectly well, despite the alleged issue of it beginning to collapse before it went up there!

Meanwhile, I cleaned out the ash from the smokebox - there was half a dustbin full in there! We then tackled the bungs. Bruce & Carpo were in the firebox undoing the nut on the end. I was in the smokebox watching the nut at that end. My nut wasn’t for turning! Bruce unscrewed rather a lot, and also tapped the rod through, but still my end wouldn’t turn and the bung clung on doggedly. Bruce & I decided to abandon this for today.

The tender had arrived at 11.10, so Carpo and Bruce shunted that into the yard and we coupled up loco and tender. We were a little concerned that the linkages had (once again) suffered at the hands of the uninitiated, though not as badly as last time it went to NYMR. We shall have to construct a template for guiding the three links into their respective holes!

Carpo pressed on during the afternoon, and reported: “This afternoon I removed the bung in the firebox before removing two elements to allow me to remove the bung in the smokebox. I was then able to remove the remains of the tie rods before cleaning out the tube with our drain cleaning pressure washer.

This means that tomorrow we should be able to put 20psi of air over the water and be able to ascertain the whereabouts of the leak. We shall then be able to sit down for a cup of tea and decide the next step!”

Saturday 22nd
A whole host of people turned up to help, today: Brian, Bruce, Gilbert, John T, Steve and myself; plus Phil and Stu from the Loco Dept supported Carpo (who, once again, spent the day inside the smokebox)!

The smokebox had a couple of inches of water in it, but this was probably due to Carpo cleaning out the tubes yesterday before removing the superheater tubes. John baled it out, I believe. As per plan (above), Carpo removed an inspection plug to fit an air hose adapter … except that it was too big! So, a smaller one had to be made: take one plug; drill a hole through it; tap a thread in it, fit air hose connector. However, Carpo inspected the innards and declared that there is no sign of boiler mismanagement - it all looks fine inside there.

Once the air line was attached, pressure was built up to about 20 psi whereupon the spray from the hole in the tube was clearly seen. It was about 6ft in from the firebox end, at a “4 o’clock” angle. So, the next step was to drain the boiler and remove the tube. One of the bungs had already had to be cut out, and now Carpo had to carefully cut the tube at the firebox end; heat and ease the smokebox end. Then Bruce knocked up a rod to help push the tube out, with Phil doing so from within the firebox.

The tube had to come out 6” at a time, because there is not enough room behind & beneath the regulator header to push any more through. It can’t go the other way because the tube widens, and will not pass through the narrower tube hole in the throat plate in the firebox.

Carpo will speak with the boiler inspector on Monday. He will probably want to see the flawed tube and discuss the method of replacing the tube. All being well, we shall be able to fit Skinny, and then have the annual boiler exam during November. Assuming it all goes well, we will then join in on the Santa Specials … keeping a close eye on the other tubes!

In spare moments, John managed to needle-gun a couple of rail chairs, while I finished off the four boot scrapers in the production line and then re-stocked the cafes at Todders and Winchcombe.


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