noisy alternator
 

tried this in electric section, no replies thought i'd try here.

Started the car this morning and i notice a "new" noise, have to drive across town and finally get a chance to pop the bonnet between rain storms, so listening carefully me thinks the altenator should not sound like that, so question is how much is a new one going to cost!! MY00 or does anyone know the sequence for dismantaling to replace the bearing at belt end, as the screwdrive stehoscope seems very active at the front of the alternator.

cheers ray t

Are you sure its the alternator not the PAS pump, they tend to whine..

The bearing is a roller type bearing, they can run dry making them rumble like a pair of rollar skates or if they get any grit in there they make intermittant screetching noises.

Sometimes having the belt too tight will cause this, slackening it off a little may quieten it down.

Alternators aren't hard to dis-assemble, if you've done one, you have literally done them all, as they are all pretty much the same. Removing the pulley is the only hard part, as that will be rusted up solid (so use plenty of 3-in one or rost-off-ice a few hours before).

You could strip it down and re-pack the bearings with some decent high temp lithium grease. But note that it'll probably come back. Or it will be likely to introduce some more grit into there. If that becomes the case, turn your radio up or track down some new bearings to press in (good luck with that - as you'll have a hunt on your hands, unless you want to fork out for a new alterantor) ;)

Got it apart and extracted the bearing, and seems my guess was right it's definitly got a couple of flat spots, so just ordered a replacement from RS part no for ref is 442-0076 bearing physical size is 40mm o/d 17mm i/d 12mm thick with synthetic rubber seals, price £4.39

bearing part ref is 6203-2RS1


ray t