Hey guys, I need some help to determine how to fix this serpentine belt issue. Now, when starting the car, the serpentine belt will just pop off. During my inspection, I noticed two things.

First, the tensioner pulley, and the a/c pulley do not line up with the crank pulley. I do not have alot of experience with serpentine belts, but this is like a red flag in my mind of why the belt keeps slipping off.

Second, the belt appears to be missing some of the ribs on it, aprox half.

Now, I can only replace the belt, but i don't want to replace it if that is not going to fix the problem. Can anyone give me an idea if i'm on the right track, or if it is really just the belt? This is in a 2000 monte carlo, with the 3.4liter v6 motor.

 

check to make sure your cranck pulley is tight... ive got an 05 gtp and for some reason mine started losseing up and missalighned my supercharger belt... also could be your tensioner pully... take the belt off all the way where the pully is free try to wiggle it around and see if the bearings are shot...shouldnt be anything to major could be belt could be the tensionr...

 

tensioner seems fine, spins freely no play in it really. The crank pulley is also tight, I turned the motor over a few times makings ure itwas tight.

 

Tooks some pictures outlining my concerns with the crank pulley. Links providced below. Warning, big pictures:

http://img836.imageshack.us/img836/7950/dsc00124wv.jpg

http://img696.imageshack.us/img696/7987/dsc00125vw.jpg

 

Looks like the pulley bracket is warped. I had that problem on my old cavaliers tensioner. I was told GM doesnt make them very strong and that usually if your running aftermarket addons that it needs to be upgraded.

 

The tensioner has a little bit of play and should be replaced eventually, but the source of the problem was that the harmonic balancer failed. We replaced it in like 30 minutes.