Spun Rear Wheel Bearing, Do I need to replace the control arm? Options

[skeates]

Just pressed out the rear wheel bearings to find that one of them had spun pretty bad. Left some scorch marks in the seat in the control arm and what looks like a pretty bad score. I tried to get some pics, but the cell phone camera couldn't quite get the right exposure. Am I correct in assuming that I would need to get these machined in order to use them again? If so, is there enough material in there to machine them and still have enough interference for the bearing to seat correctly - or do I need to replace the control arms? I'd appreciate any help possible!

[davesprinkle]

The term "spun bearing" describes a failure that only applies to babbit or plain bearing, like the crank main-bearing and rod bearings. This typically happens when you lose oil-pressure for some reason. As a result of the reduced oil film, the inner surface of the bearing locks onto the journal and then spins in the case -- hence the term "spun bearing". When this happens, the oil-feed hole in the bearing gets covered up, and then your previously-meager oil pressure drops all the way to zero. Game over, man, game over.

Regarding your wheel bearing, I agree with the other posters:
-- Don't worry about minor scratches in the bore of the trailing arm
-- Do not machine out the trailing arm bore -- this will ruin the intended press-fit of the bearing.
-- Do not install a set-screw. Seriously. Do not.
-- Clean up the bore and press in a new bearing. Press on the outer race only. If you press on the inner race, then just buy a new bearing and do it all over again.