FAQ: Fragged Tensioner/Idler Pulley Reports & Questions

ok so after I paid a guy to replace both of my belts I have a very large vibration/rattling problem at exactly 70mph and up. any ideas what would cause this? Note: after receiving the car after the job was done I had to tighten the front wheels because they were very loose.

Have you had a chance to bring it back to the shop that did the job and have them look things over.
They wouldn't have to pull the wheels to replace belts. Did you have other work done?
May want to pull the wheels that were loose and inspect the condition of the wheel / hub studs to see if they are damaged at all from running loose wheels.
Remember to torque your wheels to 100 ft/lbs

I torque my wheels always to about 95 ft/lbs. and the hub studs are still in perfect condition. ya I will take it back to the shop and have them look it over. I just hope carx won't charge me for it since it was their goof up

i changed the waterpump on my riv over the weekend only took me like 5hrs lol!

This damn car is starting to drive me nuts!

I heard a clack clack noise so I popped the hood and noticed the inner most belt was deflecting to the left somewhat. It's eaten a rib off of the belt. It's not down it right now. Since it's moving, should I suspect the tensioner or crank pulley or another pesty idler pulley?

Rickw wrote:

He is going to have to do it again soon, to replace the son-of-a-bitch pulley.

Not to say i told you so, BUT......

I would change all pulleys and be done with it.

Probably an idler. Replace them all.

lol You adamantly told me to change it. Guess I'll have to get that last bastard of an idler pulley and check the crank while im down there.

Alright well the bouncing issue isn't caused by the one idler pulley I neglected. Thats on the belt path for the other belt. It's not bouncing currently so I really don't know what the deal is. If it were the crank wouldn't both belts have done it?

I really wish I would have had my camera with my so I could have shown you guys it bouncing towards the passenger side a bit and making a clack clack type noise. That noise really made me think it was the tensioner but there are no issues with belt tension that I can feel or see.

There are idlers and tensioners. The tensioner is just a swinging arm with the same idler on the end of it, which should be replaced too. You don't have to replace the whole tensioner, unless it isn't maintaining belt tension... but the tensioner pulley may need replacing.

Remove the tension of the belts. Slip them off the pulleys and check all pulleys again for any play or side to side movement.
If when you replaced a pulley earlier it may not have seated on it's shaft completely. If that's the case, just loosen the bolt and seat the pulley and re-torque. I've seen that happen before to the best of mechanics. It will sometimes cause a pulley to wobble a bit or just make the pulley run out of alignment with the rest and cause a belt issue.

The tensioner pulley was the pulley that originally broke causing me to replace 3/4 of the pulleys.

I removed and reinstalled it. The alternator pulley was the only one to exhibit any signs of movement and maybe only 1/16" or so. It also had a light squeak when spinning it.

manofmany wrote:

I removed and reinstalled it. The alternator pulley was the only one to exhibit any signs of movement and maybe only 1/16" or so. It also had a light squeak when spinning it.

Well as you know the only way to fix that is to replace or rebuild the alternator.
The bearings inside are going bad. Possible other things, don't know till you disassemble it.
For most people it's just easier and cheaper to replace the whole unit.

But I dont think that was the cause of belt getting torn up this time.

Rickw wrote:

manofmany wrote:

I removed and reinstalled it. The alternator pulley was the only one to exhibit any signs of movement and maybe only 1/16" or so. It also had a light squeak when spinning it.

Well as you know the only way to fix that is to replace or rebuild the alternator.
The bearings inside are going bad. Possible other things, don't know till you disassemble it.
For most people it's just easier and cheaper to replace the whole unit.

But I dont think that was the cause of belt getting torn up this time.

Neither do I. I'm really at a loss of what it could have been other than the crank pulley. Time will tell if thats it or not. Minus that one rib that is partially rubbed down it's running smooth and normally. Put 80 miles on it today with no issues.

I guess all you can do is keep a close eye and ear on it and see what develops.

Quote :

I heard a clack clack noise so I popped the hood and noticed the inner most belt was deflecting to the left somewhat. It's eaten a rib off of the belt.

This is what happens when the belt is not routed correctly on the crank pulley. The furthest left (outside) rib was likely riding on the edge of the crank. How long has it been since last time you've had the belt off?

3 Weeks ago he replaced belts and some pulleys.

Yep, that's probably what happened then. I did the same thing the first time I swapped pulleys. Saw a white line developing near the outside edge after 3 days of driving. I found the belt was one groove off on the crank pulley. The belt lasted a long time, but that line never went away.

There's almost no way to tell unless you check the crank specifically, or you happen to see the wear in the belt before it breaks.

Yeah I'll just have to keep an eye and ear on it and see what develops. As usual, I appreciate your insight Rick and AA

I don't think there's anything wrong with your pulleys. Just make sure the belt is centered on the crank correctly. Like this:

Took almost 7 months but my belt is almost completely shredded again. All the pulleys appear fine. Guess I'll get another belt and see what happens.

manofmany wrote:

Took almost 7 months but my belt is almost completely shredded again. All the pulleys appear fine. Guess I'll get another belt and see what happens.

One edge shredded? The whole thing? I noticed with one replacement idler pulley I got that the centerlines of the pullies was not the same - I think it was boxed wrong and somebody just saw that it was the same size. Could be something like this? Take a few pics of the belt while it's on the motor?

i also had a similar problem with my after market tensioner. there is a protruding wedge,for lack of a better description,along side the top of the tensioner that contacted the bottom of the alternator. this prevented the tensioner from freely moving and caused my belt to shred a few times until i noticed the defect. i filed the protrusion down and since no problem. check it out.

This is from the belt not being routed onto the crank pulley correctly (see illustration at bottom of previous page). Sorry, tried to warn ya!

AA wrote:

I don't think there's anything wrong with your pulleys. Just make sure the belt is centered on the crank correctly. Like this:

Aaron makes a great point. My Regal threw the SC belt over one tooth to the outside of the CS pulley and the result was that end of the belt getting shaved down. I luckily caught it right away because I'm always under the hood of that car. Ever since, the belt has been fine (although I probably should be getting it another SC belt soon). These cars shouldn't shouldn't have a belt misalignment issue one way or another on their own (granted all pulleys are functioning properly) but it can't hurt to feel around down there to make sure. *do this while car is off obviously* In my case, I had just gone down a pulley size so I swapped belts out quick. Should have taken better care to see that the belt was completely in line with the balancer.