I think that the pullry that is on my alternator squeaks. Can I buy just the pully or does the whole alternator need replaced?

 

I'm not sure if you can replace the pulley. There's no procedure in the book but others may know.

The tensioner pulleys are more often the source of noises. Are you certain its the pulley on the alternator/generator? Here's advice from E-T on identifying noises on the system. Its aimed at identifying belt squeaks but works for pulleys too:

Here’s a pic to identify the components.



Belt Squeal Courtesy E-T

You have two belt systems on your car. One is the drive belt system, the other is the air conditioner belt system. The drive belt system consists of the serpentine belt, the power steering pump, alternator/gen, water pump, harmonic balancer, idler pulley, belt auto-tensioner pulley. The AC belt system consists of the compressor, harmonic balancer, idler pulley, belt auto-tensioner pulley.

First thing you need to do is isolate which system is squeaking. This can be done by releasing tension on the drive belt tensioner and removing the serpentine belt. This is the outboard belt of the two belt systems. If the squeak goes away, then it’s the belt or a component of the drive system.

If the squeak is still there, then it’s a component of the ac belt system.
To verify this, release the belt tension from the tensioner and remove the belt. If the squeak goes away, then it’s a component of the ac belt system.

A common problem is the belt tensioner on either system but verifying which system is at fault is the proper procedure.

You could replace both belts, but you may still have the squeak. If you want to find the culprit, isolate the system, then spray the belt of the offending system and see if the squeak goes away. Try to stay away from the idler and tensioner while spraying. I find that belt dressing may be good to identify a belt problem, but it is a temporary fix at best.

 

actually you can pull the pulley off of the alternator, but it takes a special tool to do it!

and yeah i agree, usually the source of noise is usually the tensioner pulley.

 

Thanks for the tips, but I am one step ahead of you all. I have already narrowed the noise to the main drive belt, since I removed the AC belt and the noise was still there. From that point, I replaced the tensioner, idler pulley and the noise still comes back. When I had the belt off last, I spun the alternator pulley and it made a real faint squeak, so I am thinking that is the next part I will try to replace.

 

The other culprit can be the harmonic balancer-do a search TONS of posts on it.

 

Hate to point out what should be obvious, but the alternator pulley itself doesn't have anything in it that would squeek when you spin it. If the alternator squeeks when you spin it then the bearings inside the alternator are dry. You can either try taking it apart and greasing the bearings (I've done this with success a number of times) or just replace it.

 

Since the front bearing is a sealed type, I don't see how you could possibly regrease it successfully.

 

I chased the belt problem for awhile. It ended up to be the belt, even new ones squeaked till I put on gatorback belts. That was after replacing the idlers and tensioners and getting scared thinking it was the damper. I bet its the belt. The alternator pulley is an unlikely culprit.

 

Guess i should have included that. Already replaced both belts with gatorback belts. No change

 

Unless the pulley is damaged, or rusted....I don't understand how it could be causing the noise(provided this is not a decoupler pulley). If you have isolated it to the alternator, it's most likely internal.