Update from 16th December. By Terry and Ian.
Just a couple of working weeks left to go of 2017 and we have an update below from Terry on D9526. Also
an update from Ian on D6566.
In other good news, loco allocations have been provisionally agreed for 2018 which includes the first running
of D7018 in passenger service since its major overhaul. This is planned for the Diesel Gala in June and then
some subsequent running dates. Please see our loco running dates page for more information.
Saturday 16th Dec Simon and Terry trimmed the injector pump timing and tightened a few leaky hose
connections, John Cooke stripped the throttle controller valve and replaced a few "O" rings,Simon and I then
started 9526's reconditioned Paxman 6YJ and moved the loco out of the shed coupled her up to the Ferry
Van and Low Mac,we then undertook a set of engine load tests at various throttle settings which we gradually
increased up to 1350 rpm by which time the loco was straining at the brakes( Stall Test) !! We kept the
engine running until we had it up to running temperature and the cooling fan was operating.
At this point the exhaust was burning clear and the engine had a steady note,we sustained engine revs for
20 mins then reduced it down through the range to a steady tick over.
The engine performed well and the loco was shunted back into the shed which allowed us to do visual checks
We noted the replacement generator was giving a charge to the batteries ,the throttle control valve working
as required,also the overhauled Vacuum Exhausters with new vanes instantly created vacuum for the braking
Our next step in the new year is to undertake some gentle running within Williton station confines if this
proves satisfactory we plan a lightly loaded run the following week. Pictures below of engine.
To check there were no leaks following the work on the heat exchanger the previous week the cooling system
The hose was attached to the normal filling point and the radiator drain tap was left open allowing water to
flow out until it ran clear thus flushing out any loose sludge or other debris.
The water was left in for a few hours before being drained and no leaks were identified.
So I think the time is now right to put in the antifreeze.
Also, the air main reservoir was connected up to an external compressor to investigate a problem with the
proportional brake when in air mode.
This issue had been discussed with Railway Brake Services and their view was that as it performed
satisfactorily in vacuum mode it was unlikely to be a problem with the Triple Valve itself and was more
probably a sticking valve or blocked choke in one of the sealing blocks or maybe an Air Vacuum Isolation
Valve (AVIV) problem.
As we have a spare AVIV in the Class 47 spares that was investigated first.
Having confirmed the fault was still extant the removable valve seal and plug from the air side was swapped
for the one from the spare unit, the valve insert was visibly in better condition.
Amazingly this cleared the problem, every brake application now giving a correct proportional response from
the the loco brakes!
John Cooke has fitted one of the new AWS power converters into position as a further step towards
reinstating the AWS.