Thursday 20 October 2016

Maintenance Update (chuck, tube, valve, header)

Saturday 15th
Re. the leaking tube: Remember the tubes being sponsored, back in 2009? The question has been asked: whose tube is it? Well, it is tube number 5, but I won’t say who sponsored it in case they feel morally obliged to buy a replacement! But if they do …

Carpo has phoned another friend (actually, the boiler expert from Riley’s came here by luck & fortune) and has decided that we shall definitely remove the offending tube and replace it with a narrower one. It will be a challenge getting the old one out and the new one in, but if we don’t try …
Carpo promptly ordered the new tube, and it will be delivered on Thursday.

Bruce tested the new dustpan and brush.

He’d bought a new chuck for the pillar drill (because the old one was no longer going round in circles) and so he fitted that.

During the morning Bruce also painted the bottoms of the four rail chairs in the boot scraper production line:

The paint dried in the sunshine, and I applied a green primer coat to them during the afternoon. In the morning I was making wooden wedges that hold the brush in place on boot scrapers.

We decided to point 2807 northwards when she returns, not because she will be missing Yorkshire, but because she has been facing south for over two years. It might even out any wear that happens over time.

When the new narrow tube arrives, Carpo plans to test out the feasibility of fitting it without removing the regulator header, by trialling it on 2874. If it works, then that’s what we do on 2807. If it doesn’t work? Then Plan B will be required!

Sunday 16th
Andy Bryne was up North keeping an eye on 2807, and will watch over her while they pack her up to
come home. He sent the following photos:

2807 at Levisham
Grosmont viewed from 2807’s cab
2807 at Grosmont

NYMR staff in wartime dress

Andy also reported:
“The NYMR should provide us with any snag list but one thing that didn't work yesterday was the
steam heat mason's valve; it rotated but nothing happened apparently.”

Ah, well it wouldn’t! You can turn the top of the valve to your heart’s content, but unless you turn the steam on, nothing will happen!

The wheel on the top of the Mason’s valve adjusts the drop in pressure from boiler level (225 psi) down to coach level (typically 40 to 60 psi).

You do need to open the steam valve first! Normally, you don’t dare touch the Mason’s valve - they have a reputation … Ah, well, we’ll sort it out when she’s back.

Wednesday 19th
I popped in to Winchcombe first, to get signatures on 100 Club winners’ cheques.

Fred, Bill and Ray were working on the siphon. Ray had spotted an apparently loose board, and was removing it as I was there. He discovered that the two screws in the bottom of the wood were not doing a lot … one had gone into a gap, and the other into some wood that was decayed!

Over at Toddington, Gil, Bruce and John G were generally deciding what to do. The electrics in the yard are being upgraded, which meant we had no power down by the van or for the compressor. The latter meant that rail chair needle-gunning could not take place; the former meant finding a socket that did have power so that we could have a cup of tea!

Gil and John went over to Winchcombe, where they could be doing something useful on the siphon restoration.

I applied a top coat to the four chairs in the production line.

There was some discussion about how to proceed when 2807 returns on Thursday, but there can be no simple plan. There are a number of steps to carry out, and depending on the results, what the next step will be can only then be determined.

If the trial fit of the slimmer tube in 2874 works (i.e. we can get it in successfully) then we shall move towards doing it on 2807. If we can’t get the new tube in, then there are three options: (i) leave the plugs in 2807 and run to end of year to see if more tubes blow; (ii) grind a small piece off the bottom of the regulator header if that will be sufficient to get the new tube in; (iii) take the regulator header off completely!

Options (ii) and (iii) mean getting the errant tube out, before which we can hydraulically pressurise the boiler and inspect the tube to see where, and how much water is leaking. Then it has to come out: option (ii) a bit at a time because of space limitation; option (iii) possibly in one piece.

Then things depend upon what we find by inspecting (a) the errant tube; and (b) the other tubes. If the leak appears to be a one-off caused by some intrusion in the metal, we fit the slim tube. If there is any other visible cause for concern, then it could be we replace the lot - do a 10-year overhaul of the boiler, in fact. Indeed, if at the end of it all, another tube does decide to blow in service, then the whole set of tubes has to be considered suspect anyway, and full replacement will follow.

2807 was due back on Thursday. “Slim”, the new tube, is also due to arrive on Thursday. However, this from Andy Bryne this evening:

“I was informed by the NYMR P-Way staff that the low loaders would not be arriving until tomorrow (Thursday) although everything was ready for loading at the NYMR end. So I guess 2807 may not be back at the GWSR until Friday. “

I’ll keep you posted with progress. Meanwhile, keep your fingers crossed!


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