Preparing Clayhanger Yard for Kettering, I gave all the locos their usual pre-show wheel clean. Reaching the Pug, I remembered that it needed a little more attention than a polish with the fibreglass pencil.
With power applied to the wheels, the motor whirred away but nothing else moved. Splitting the body from the chassis, the cause was obvious - the worm gear was completely worn away.
Luckily, one end was intact so with a little levering and then the attentions of a gear puller, it was taken off the shaft, turned around and shoved back on. With everything screwed back together, the wheels on the train go round and round again.
With a bit of luck, the gear will survive the final 3 days of exhibition and then the loco can go back to being a display case queen again. Once day, I'll need to find something metal to replace the nylon(?) item, but hopefully this has staved that day off for a while.