Another rather damp weekend with Keith Wright, Robin Fransham, Mark Hallet & myself in attendance.
After some rather good detective work by Mark, a special design relay was obtained for the DSD speed switch circuit board. This was repaired first thing and the box remounted on 56040 (but not before it was dropped on my head! – lump available as proof!) An attempt was made to start her, but the batteries were just that little bit too tired to get the speed up, so she was put on charge for the morning whilst work began on removing the axle box covers. The covers were removed to check the condition of the bearings and the grease, the outermost being very awkward as the cab steps had to be removed first! Sounds a fairly easy task, but in reality took several hours to complete – again I was to be found in my usual Saturday position of under the bogies!
These checks revealed no problems with clean soft grease around the bearings with no signs of damage or corrosion. Robin went round with the grease gun and gave each axle a few squeezes of grease, and then went round the break rigging and traction motor blower bearings all lubed up nicely. Investigation into the speedo fault revealed a wiring problem on No.1 end cab, there are two positives and two negatives in the wiring loom behind the desk for the speedo’s, a pair of each for the main speedo and another pair for the slow speed speedo, somehow both positives were wired on the slow speed speedo, whilst both negatives were wired on the main speedo! This was rectified and everything was ready for testing.
Oystermouth burst into life, but after a few minutes the air was not building as expected, a rather large gushing noise was heard coming from the parking brake frame. Upon investigation it was found that the parking brake interlock valve had stuck, the engine was shutdown and air isolated from the parking brake. The valve was stripped down to reveal that it was full of that wonderful substance that gets everywhere – water! The valve was removed from the loco, stripped, freed and lubricated before being rebuilt and replaced on the frame. Time to press the button again with fingers crossed! This time she fired up and was building fine, checks revealed that whilst removing the interlock valve, we had accidentally damaged one of the pipes leading to the valve – one of the problems associated with fixed pipework which has to be strained to release valves etc. This was patched for testing purposes with a solution Heath Robinson would have been proud of! Air then built up nicely and she took power straight away with no problems!
The DSD time was allowed to elapse and this dumped the main air pipe confirming that the newly repaired DSD box/relay was working, after 2 minutes time delay the pipe was returned and power could be obtained again. A quick trundle up the siding proved that the main speedos in both cabs were working, and on the return the slow speed control was switched in proving the slow speed speedo’s were working – and that the traction control module worked well as she was increasing/decreasing power in order to keep a steady speed. We shut her down for the night, removed the temporary repaired pipe and another pipe from the unloader valves so that replacements can be manufactured. All in all a rather wet but successful day!
