I thought that one of the characteristics of a bad harmonic balancer is that you can pull the belt (by turning the pulleys) back and forth when the engine is off. Normally you should not be able to do this (without lots of effort!)

when you say pull the belt are you saying turn it with it still on all the pulleys? And if so is that a full turn or should it not turn any?

thanks

thanks

Normally you can't move the belt when it is on the pulleys without significant effort. But if the harmonic balancer is broken, the belt and pulleys will move back and forth.

OK...My Problem is still here...I changed the water pump and the whole tensioner assembley..

Like I said it rattles and clunks when I start it...then if i press the gas it stops..or drive it stop..and like lowlyfe83 said it starts back when i let off the gas..

Now....I took the belt off the pulleys and started the car....NO SOUND so I know it is pully related..I have a mechanics stethescope and can't pin-poin the rattle..took it to a couple of local mechanics and 2 local shops, they used a hose to pinpoint it and so did the guy at advanced and autozone..they could not...they said for a noise that loud it shouldn't be hard to find out where it is coming from...

one said it could be the harmonic balancer but usually you would be able to tell.......

I had the alternator tested and they spun it on there thing..and it made no sounds....does that spin machine have enough force to make it clack if the alternator was the problem?

Another thing...the pulleys do turn with the belt on..they can go back and forth..but the go backswards some and then they stop and won't go back any farther...(western auto tech discovered that)...however he say they should be able to turn freely but something is stopping it but we took the belt off and all the pulleys turn freely..we did not try the bottom one though! He turned it with a wrench on the water pump and he did not have to strain or anything to do it

So fuddydudd121 are you saying that they should not turn at all with the belt on?

and if they do it is a sign of a bad harmonic balancer?

Also could someone please verify this for me..as there is no one that i know with a
bonneville!

Oh here is another thought...when i turn the ac OFF it rattles worse...when I turn it on it quietens some..but still rattles..I know that sounds backwards but that'* what it is doing!


i appreciate all the help you guy'* have given me!

thanks

That does sound like a harmonic balancer. Here are some old threads on the subject...

Wesley,
I've had to have a harmonic balancer replaced. It made a thwoop-thwoop
noise (Ok enough laughing). The outer pulley separated from the inner
crank and the pin that holds them together through the rubber was making
noise. It made more noise at idle.
I replaced my supercharger at 175000kms because it was making noise.
There was a lot of play in both bearings. Finally I replaced the catalytic
converter and that quieted everything down.

DG

On Mon, 29 Oct 2001, Wesley Combs wrote:

> Hey has anyone had anytrouble with the Harmonic Balancer on their
> Bonneville? About 2 months ago the car started making alot of noise and I
> determined that it was coming from the supercharger nose piece so I replaced
> that and still have a noise. Then I replace the top Idler pulley and still
> have a noise. The bottom Idler pulley is making some noise but I noticed
> that the Harmonic Balancer has some rubber on it and that rubber is rotting
> and it almost sounds as if the sound is originating from that piece. Any
> body replaced this? Any input is appreciated.
>
> Wesley
>

----------------------

Subject: RE: [bonneville] 1991 SSE Need help with noise in engine


ADVERTISEMENT


>From: "vern" <avern1@y...>
>Date: Tue, 27 May 2003 01:05:33 -0000
>Subject: [bonneville] 1991 SSE Need help with noise in engine
>
>Hi Everyone, I'm Vern'* wife and we need help with our SSE. We have
>a strangle rattling sound in the engine (thought it was the water
>pump). We replaced the water pump and it still continues. However,
>it goes away above idle. Also, is the harmonic balancer suppose to
>move back and forth by hand with the engine shut down? Vern'*
>sitting on the couch trying to figure this thing out (lol) HELP!!!!!

The damper'* toast. Known problem and it happened to my '95 SSEi. 8^(
If you get the p/n from your dealer and shop around on-line from places
like Flow Chevrolet and Chuck Hutton you can save some money; when I did
mine last year I think I paid around $120 for a new damper. Good luck!

Brad

-----------------------------

Subject: RE: [bonneville] Clunks and Other Various Noises


ADVERTISEMENT


Sue:

Good to hear from you!

First thing to check for clunk is the sway bar end links. I had to replace
mine. Also the sway bar mounts to the chassis. The struts are probably OK,
however if they didn't change the strut rotator bearings when the struts went
in, that could be it. I had the bearings go bad and replaced the struts then,
even tho the struts were still good. It'* the labor factor...

Failing alternator makes a whine proportional to RPM. Water pumps reported to
leak before full failure. I changed min as a precautionary measure at 110K. Low
rattling noise is highly indicative of a harmonic balancer failure. If it goes
away at higher RPM that'* it.

Supercharger oil never has to be changed according to Magnuson. I'd think once
a year is plenty even for the paranoid.

I sold my Bonne but I'm still answering questions to spare folks what I went
thru. BTW, '92 SSEi mint shape wait many new parts sold for $ 6800. with
114,500 miles.

Dave B

-----Original Message-----
From: exoticmwa@a... [mailto:exoticmwa@a...]
Sent: Monday, March 13, 2000 8:13 PM
To: bonneville@o...
Subject: [bonneville] Clunks and Other Various Noises

From: exoticmwa@a...

Hi.

Last thing I replaced on my Bonnie was the struts. Now the thing is making a
clunking noise - sounds like the passenger side front and rear. One mechanic
told me to have Tires Plus (the ones who replaced the struts) pull the strut as
it could be bad. Has anyone ever had a strut go bad after a few weeks?? I've
had everything else looked at.

Also, a mechanic said that the noise coming from my exhaust could be either the
alternator or water pump. When I mentioned the supercharger he shook his head
and said that wasn't it cause he owns one. Not sure what he'* talking about but
it'* kind of a low rattling noise. When an alternator or waterpump goes out does
it actually made noise coming out of the exhaust. I sure don't remember that in
any other cars.... He said pray that its the waterpump cause the alternator is
spendy!

BTW, I replaced my supercharger oil again. I'm thinking about doing it 2-3
times a year. Does that sound excessive???? Paranoia will do that to you.

Harmonic balancer I do believe that is my problem..took the tire off this morning and can definetly see that the rubber is clearly seperated all the way around the pully..what caused it to do that?


nowis it hard to get off? I see one large nut/bolt in the center of the pully.

thanks

any tips appreciated

Can teh car be driven like this (about a week) untill I get itfixed?

thanks

From what I hear, it is a difficult job. You need a special puller from GM to remove it properly. If you have the cash I might recommend that the dealer do it... I've never done one before so I can't give you any personal experience.

How long has it been rattling? Another week may not hurt it, but you may want to get it fixed soon.

Last questions..

1. Is the harmonic balancer the whole bottom pully?

2. and is it near the crank sensor (is it best to replace it while there, or is it too much added work)

3.. Can I purchase one used or get one off another bonneville?


thanks

Okay, here'* some thoughts on pulling the harmonic balancer.

Since your signature lists your car as an SE, I'm assuming that you don't have a supercharger. In which case, you could use one from another 3800-engined car (like from a junkyard), but are you sure you'd want to? One from the junkyard is likely to fail fairly soon anyway (age, miles) and you'd end up doing it again anyway. It'* my understanding that GM changed the design on these H.B.'* to increase the service life, and they are currently available. They're kinda pricey, but that'* really the only way to fix it. I mean, they can't be "re-rubbered" or anything like that, at least not to my knowledge.

It'* been awhile since I did mine, but I used a run-of-the-mill balancer puller to get mine off, but I did have to get some specific bolts from Lowe'* to fit the threads in the hub of the balancer. It can be done by pulling the belt, the right front wheel, the splash shield, and you're there, with full access to the balancer. The center bolt on the balancer is pretty tight, so you'll need some way of locking the crankshaft so it doesn't turn while you're trying to loosen the bolt. I had my dad hold a stout screwdriver between the teeth of the flywheel and the notch in the transmission bellhousing while I was breaking the crankshaft bolt loose. Once that bolt'* loose/out, you just use your balancer puller and pop the balancer off.

Putting the new one on is basically the reverse of taking it off. I can't remember the torque for it for certain, but I think it was like 105 lb-ft (that is on a SC car, Non-SC may be lower). I can check tomorrow to be sure. If there'* anything that I've missed, or anything you don't understand, let me know ....

Cheers,

Brian