This afternoon my shop vac started to sound like the bearings are going out. I check everything without taking it apart and nothing seems wrong except for the sound it now makes, particularly at start up. Could be the fins inside? are broken but it sounds like motor bearings to me. i'll have to take it apart but I was wondering if anyone has done any similar repairs to one. It's a Shop Vac 12 gal., older, probably had it 15-20 years.