Conveyor gearbox was getting increasingly hot and juddery.
Opened up, no oil and the brass gear has shredded somewhat, lots of brass filings around the perifery. Bearing wasn't brilliant either.
In an emergency, i'd have flushed it out, replaced the bearings and put some oil in it in the hope it might make it last a few days until a replacement is found.....but i had a slightly slower version i could fit. The conveyor is getting scrapped soon anyway.