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Crank pulley/harmonic dampener identification?

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1LE

20+ Year Contributor
1,347
4
Aug 1, 2002
Sylvania, Ohio
So, my DSM has had the cold start 10 second squeal going on for a few years now. It has recently also developed the squeal when the lights and defroster are on. So, I really need to get this fixed as that's unacceptable! :)

Belts are all tight and the water pump, power steering pump, and alternator spin pretty well by hand. So, I would have to suspect the harmonic dampener/crank pulley. Now, at the last timing belt change (perhaps 2 years ago) it was inspected by a shop and declared good. Today I went ahead and pulled it myself again (since the problem is getting worse). It really looks quite good (I see a tiny surface crack when inspecting VERY closely, nothing at all obviously wrong beyond that), but is at least 15 years old as neither myself nor the previous owner changed it. I hear other people have reported that replacing ones that look perfectly fine has solved their problem and I'm willing to throw the ~$140 at it in the hopes I'll have the same results.

My problem though, is that I see there are different part numbers for different year cars. '90-92, 93/4, and '95-99. I've got a '95 body with a '92 block... I really don't know which part to order. Is there some way to tell by looking at the crank pulley I have now (I looked, but didn't find any obvious part numbers on it)?
 
I would invest $50 and put all new belts on before replacing the balancer. Just because they are tight, doesnt mean they are not glazed which could also be why they are squealing.
 
Order your pulley according to what motor you are running. Also I had a squeal on start up and It turned out that the ac tensioner was going bad or something because my timing cover had a groove in it from where the tensioner was rubbing.
 
First, have you identified which belt is squealing? I would assume the alternator belt, since you described the issue worsening after certain accessories are on. You should confirm this.

Second, are you using an OEM damper? If so, it's highly unlikely the damper itself is causing your belt to squeal. I would thoroughly check all of these below before I went replacing random things:

- Belts are properly tensioned
- Belts are the correct size and in good condition (no cracks, rips, tears or glazing)
- No oil or fluid leaks in the vicinity of the belts (oil or coolant on the belt surfaces will cause them to slip)
- All tensioners are working properly (Alt tensioner, A/C tensioner and PS steering pump tensioners all in good working order

I'll bet one of these things above is the root cause of your problem.
 
I've been through a couple sets of belts already. Does not change anything. I've looked for anything wobbling/grooving, nothing found so far. I don't have A/C.

The alternator drive is definitely involved. In the past, I've noticed it with power steering as well. Now that you mention it though, I have NOT noticed it with power steering since the latest belt swap. The vehicle does have an OEM damper (but there are tons of posts about them delaminating and causing exactly this squealing that I get). Other than water and salt that gets onto the belts and makes it even worse on bad weather days, they're clean (as mentioned, even with brand new belts it does the same thing).

I guess I'll just put it back together and keep driving it. Eventually, something will either give out or become noticeably bad...
 
I may have found the root cause. While reassembling I noticed that the alternator can shift a little on the pivot, resulting in a slightly different angle on the pulley. Instead of letting it settle naturally, I held it over towards the other end of travel while tightening. The belt is actually a smidge looser now that it was before, but no more squeal (so far anyways)!
 
I may have found the root cause. While reassembling I noticed that the alternator can shift a little on the pivot, resulting in a slightly different angle on the pulley. Instead of letting it settle naturally, I held it over towards the other end of travel while tightening. The belt is actually a smidge looser now that it was before, but no more squeal (so far anyways)!
I will have to look mine over because my car has started to do the same exact thing. Same as you I replaced all belts with no improvement. Thanks for posting this!
 
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