Last week we had to abandon a start up of 33035 due to the generator being soaked with condensation. So this Saturday we went armed with electric fan heater, although there was no sign of the dreaded damp despite the temperature being close to freezing. After an hour warming up the generator, we went for a start, and the engine duly burst into life. However, the ammeter showed that the batteries were not charging, so it was quickly shut down and the charge relay given a prod. Second time, it duly behaved and the batteries were charging nicely shortly after the engine was started. The exhaust puffed out some white smoke for a few minutes, but soon cleared in the usual environmentally friendly Sulzer fashion.
The loco was not letting us off so easily though, as it refused to take power at either end. Every relay and interlock in the power circuit was checked and cleaned, each time firing up the engine and trying for power. It was just being very obstinate, and every possibility was exhausted until we were at the point of giving up. Then all of a sudden it decided to work, which is a bit disconcerting as we could not point to the cause other than the loco having a good laugh at our expense. Next time we will trace through the wires again and see if anything is showing an intermittent fault.
On Sunday it was back on Sherwood and Matt cleaned the field frame for the compressor motor, which turns out to be an AEI machine wound to 220V. We are not sure if this is unique or a common replacement for Crompton Parkinson motors, perhaps fitted during the dual brake programme in the late 1960′s. Carl welded a strip along the top of the nose bulkhead, and repaired the ducting for the blower motor. A coat of black gloss was applied to the new floor, and the bulkhead glossed in light grey.
A1 cylinder head was positioned on the scissor lift table and the valves lapped in with grinding paste. This was followed by lapping in the spigot ring that makes the seal with the liner. Fortunately, the valve and spigot ring faces were in good condition and required a minimum of lapping to restore them.