spun bearing

The motor did have a spun bearing now I need to know how to polish the crank before I put the new bearings in. Is there any special cloths sand papers ect to use or do I just use emery cloth????

Usually when the bearings spin, the crank journals must be machined to recreate the smooth surface required. Even if the journals looks okay to the eye, it might be rough or out-of-round enough to destroy the new bearing.

I use 180 grit emery cloth to lightly polish journals only if I am replacing worn but okay bearings. If they really did spin, machine the crank first.