Sunday, 11 March 2018

Maintenance Update (ejector, injector, split, valve)

Last week’s conundrum
Several people (Gil, Andy B, John G, Stu F, Peter T) commented on the hole in the smokebox. The short answer is that it is for a large (4-cone) ejector.

The long answer is: 2807 has a Standard No.1 boiler and hence a standard smokebox to fit. This type of boiler is also used on certain passenger locos (Hall and Manor in particular). Passenger stock is vacuum fitted for braking, whereas in GWR days, most freight wagons were not. Passenger locos therefore had to create enough vacuum quickly enough to cause all the brakes to be pulled off on every coach. Freight trains probably only had brakes on the engine. This was no big deal, because they would rarely go above 30 mph. In the passenger loco cab, the small ejector (used just to maintain vacuum when stationary) was supplemented by a large ejector which could create vacuum much more rapidly. The steam used in creating the vacuum is exhausted into the smokebox via a pipe that runs alongside the boiler, below the handrail. Inside the Smokebox, the exhaust from the ejector is connected into the blower ring.

Two theories emerge: Our boiler (numbered 8270) had previously been used on Toddington Grange, Highnam Grange and Bostock Hall. Therefore, there would have been a large ejector and hence the hole would have been used for the ejector pipe (assuming the same smokebox was retained). Also, it is likely that Swindon would have made all smokeboxes for No.1 boilers with a hole, in anticipation of the boiler/smokebox being used on a passenger loco at some stage in its lifetime.

Tuesday 6th March
Mark Y spent time going round the plugs and mudhole doors, nipping them up for us.

Wednesday 7th
* Steam Feed to RH Injector leak (Collar joint)
The pipe from cab to injector is an awkward beggar to get out. Bruce and Nigel are in the cab with a huge spanner; Gil and John G are removing the nuts at the injector end.

The collar is towards the bottom of the pipe. Gil & John cleaned up the pipe but could see no sign of a leak. Gil is working out how to seal the pipe and make an adapter such that we can pressurise it (with air) and look for a leak. Gil found a drawing of the top nut from which to make an adapter.

John P finished his mechanical exam of our loco, and found a couple of missing split pins; a loose bolt, and a loose rivet on a die block.

Regarding the groan from the cylinder when 2807 was last shunted, by pushing the reverser into full forward, it opened up the exhaust steam port on the LHS valve, so it was possible to dribble oil down the port into the cylinder. Later, as 2807 was shunted up & down prior to going back into the shed, there was no further groaning … and rusty oil dripped out of the drain cocks!

* Back Safety Valve lifts at 220 psi
We decided to take no immediate action, as it is sensible to wait until she is properly in service before verifying the pressure at which a valve lifts. Experience has shown that it varies.

* Weld broken on smokebox door handle (inner handle for dart).
Someone removed the handle and took it away to be welded. Last seen in a queue awaiting its turn.

* LHS J-cock leaking.
Bruce tightened up the J-cock. He’ll monitor it when in service to see exactly where the steam is leaking from (or if he has fixed it).

I fixed the exploded tyre on the grotty trolley. Even this wasn’t easy - as I removed the wheel to
start work on it, several ball bearings made a run for it! Only found one.

Saturday 10th
Missing split pin from a spring was deemed a “red card”. A bar passes through the top of the spring connecting it to the axlebox (white arrow, right). The split pin passes through sideways to prevent the rod from rotating or dropping out.

It is a challenge to reach, and even more of a challenge to extract the bar. We could not simply push another split pin through - the bar had rotated! To release the bar, we had to jack up the loco frames sufficient that there was room to extract it; then jack up the spring to take the force off the bar. Believe it or not, doing this took Gil, Bruce, John T and me all morning! After lunch we then searched for a new split pin that was the right diameter and the right length. Bruce cut a slot in the end of the bar, parallel to the split pin hole, such that we can see it to line up the holes. Most of this task involved me laying on the ground between the frames; Bruce lying on the ground outside the frames; Gil kneeling down, and John trotting to & fro with tools!

Then came the news that we are needed on Tuesday as standby loco! The usual last-minute panic ensued. Valve covers needed fitting; running boards putting back; the injector pipe refitting …

Valves at 3pm

3.30 pm

4.45 pm

Gil, John and I attacked the valves: fitting the covers, then the “nose”, then the cladding. Followed by the running boards, inspection flaps and lamp irons.

Meanwhile, Gil abandoned me and John to help Bruce. John also helped them by making a joint (aka gasket) for the end of the injector pipe. It was decided to ignore the leak, as it was not that serious, so Bruce annealed a copper joint for the top end. As John and I departed after completing our work, Bruce and Gil were still desperately trying to persuade the injector pipe to go back where it came from. Since Gil took it out, he ought to know how to get it back … without taking the entire cab apart.

At 11.25 pm, Gil reported:
“The RH Injector steam supply pipe has been re-instated. It still requires testing to determine the extent of reported leakage. The brake valve exhaust pipe has been put back in place and the cylinder drain cock linkage re-connected.

It is recommended that a steam test be carried out to check the integrity of the newly made joints and check the condition of the injector steam pipe.”

For those of you who would like to see 2807 in action, she is rostered for:
(Train 3 on:) March 30 & 31; April 1, 2; then from 17 to 26 inclusive, 28, 29.


Saturday, 3 March 2018

Maintenance Update (hoses, snowing, inside, test)

Wednesday 28th
In case you have forgotten already, it was a tad cold. Minus three at start of play. Nevertheless, we had 2807 hauled outside. First of all, it was necessary to squeeze up the loco and tender in order to connect the main drag link. P&O came in handy as a buffer stop! Then we rolled over a pit so that we could connect the hoses between loco and tender. While that was going on, Clive was filling the boiler, initially via the blow-down valve (which is a large orifice), but at times via the injectors (which only have a 10 mm hole).

Mostly, there was Bruce and myself underneath pushing on hoses and doing up nuts, with John T acting as gopher and Gil chipping in. All of this took until lunchtime - partly because of the cold, and partly because the clamps and the nuts didn’t always want to play ball!

By 1.30 pm, the view from our van looked like this:

… and the view inside the shed looked like this!

Yes, not only was it snowing outside, but it was also snowing inside. So the consensus was to call it a day. There was no enthusiasm to light a warming fire for a steam test on Thursday, as the forecast for Thursday was worse than for today.

By the way, I was wondering why there’s a patched-up hole in 2807’s smokebox. It is as if something either was there, or might have been there in another life. Anyone know what it was intended for?

Outside, on RHS of smokebox.

Inside the smokebox.

Thursday 1st March
After a Herculean effort by Mark Young, Mike Solloway, Clive Norton, Chris Smith and Dan Wigg and the BES insurance inspector they managed to get 7820, 7903, and 35006 through their annual steam exams today.

Friday 2nd
Apparently, having warmed things up already, Mark carried out a steam test on 2807 on Friday. The following defects are reported for our attention:-

(1) Top row LHS plugs wisping steam
(2) Slight seepage from mudhole doors: Front & back middle (Bottom), LHS Top Rear
(3) Steam Feed to RH Injector leak (Collar joint)
(4) Back Safety Valve lifts at 220 psi
(5) Weld broken on smokebox door handle (inner handle for dart).

Bearing in mind the appalling conditions (Winchcombe was cut off for most of the day) this was well above and beyond the call of duty.

Saturday 3rd
Only three people arrived at the railway today, and we all left at 11.30. Apart from rabbit tracks, mine were the only footprints leading round to our van! I applied an enamel top coat to six rail chairs and then decided enough was enough! The side door to the loco shed had not been closed (due to a build up of snow), so I freed that and closed it.

Thank goodness for traction control! It was a struggle getting out of the car park. Stanway Hill was closed. There were large drifts on the road between Winchcombe and Toddington, though passable as one lane at the worst point. The road from Toddington towards Tewkesbury was closed due to a fallen tree.

For those of you who would like to see 2807 in action, she is rostered for:
March 30 & 31; April 1, 2, 17 to 26 inclusive, 28, 29.