Our Bosch free-standing fan oven works well except the fan won’t start unless it’s just been running or has a push start with something to get it cranking over for the first spin.

Have tried taking fan off to check the drive shaft, seemed to work with cover off but doesn’t seem to be hitting the cover. There was a little bit of fibreglass fluff below the shaft that it may have been touching.

Any suggestions on how to lubricate or clean the shaft better?