Rookie here, just changed the fan belt, came out to check everything was spinning and noticed this inner part on the AC pulley slipping, sometimes spinning with the pulley sometimes not. I'm guessing this just needs tightening up but wanted to come here to make sure, and also to ask what that part is actually doing. Is this meant to spin with the rest of the pulley? Is tightening the bolt on the face of the pulley the appropriate fix? The AC was off at the time, also with a blown fuse which may or may not be related. TIA!