How's it goin everyone I have a 98 ls1 z28 6 speed it keeps throwing belts so I replaced the tensioner pulley just to have the new one throw the belt again this time on the inside I think bc it ripped the pulley and part of the tensioner ripped the bolt out. all I can think is it threw the belt on the inside , I have never have a problem throwing belts before same running gear for over 15 years and 95k miles. my dampener does move very slightly when its rotating but not enough to really notice at all and like I said 95k miles like that. I think my new plastic tensioner pulley was just trash any thoughts would be greatly appreciated thanks !

 

...are you the original owner? The reason I ask is because my first thought is that maybe someone installed an underdrive crank pulley and/or alt. pulley along the way and maybe the belts you're replacing aren't the correct length...that's just my first thought after reading your post...

 

Thank you for responding! I am not the original owner the pulleys all seem to look stock sizes to me but who knows, my harmonic damper wobbles very slightly but I've driven it 90k miles the way it is now all of a sudden lately I've been having tensioner issues, I bought an adjustable tensioner from comp cams to replace the stock factory spring loaded arm tensioner . I found the fix on an ls1 forum this group probably so an adjustable tensioner should clear up my problem.and a new belt but we will see fingers crossed lol

 

If the damper “wobbles” it may be falling apart. The typical damper consists of two concentric masses, coupled by a flexible rubber or elastomeric ring. If that flexible ring starts to separate, the outer mass/pulley can wobble, perhaps increasing the displacement as RPM increases. Additionally, if the ring is separating, the damper is no longer functioning correctly to counterbalance the impulses of the cylinders firing and causing a small, cyclic twist that can eventually damage the crankshaft.

I’ve never looked specifically at an LS1 damper, but this might be applicable.

 

thats really good info that could be the problem I'll look into a new dampener for sure! thank you for the input ! 👍🤙

 

Belt off, see if you can move the outer ring/pulley by pulling on it by hand. It shouldn’t move at all. Depending on how wide the rubber ring opening is, you might be able to see cracks with an inspection mirror. With the belt off, check all the pulleys for being loose.