Please read this if you think you can help. I'll try to make this as short as possible while including the important details.

This started a couple of days ago. I was driving and heard something like an exhaust leak sound. Opened the hood and found that my main drive belt was about 2 notches hanging off of the tensioner.

I posted here and everyone said it was the tensioner. I took one off of my friends ZO6 and put the belt back on. Upon cranking the car the belt came off in the same exact way again. I have not changed my belt and 1 or 2 of the ribs on it are worn badly from riding on the edge of the tensioner pulley for about 10 minutes on the drive home.

I fooled with it some more to figure out why the belt slips off 2 notches. I found that as the belt goes down from the tensioner it is actually touching the engine block. There is no gap there like there should be. Now the belt is coming off of the main pulley those same 2 notches instead of the tensioner.

What could be causing this? The car runs fantastic otherwise.
When I was told that it could be the harmonic balancer I went out and moved the main pulley with the belt off as hard as I could and it moved slightly but didn't have crazy play in it. When I tried to move my friends main pulley which is an aftermarket unit it was solid and didn't move whatsoever.

Please, I am welcome to all input from your experiences. I was just finishing the car this week. Have put in a lot of money on basic bolt on mods and also have upgraded the looks of the interior and exterior a bit so a big problem here does not fit into my plan very well!

 

I will stick with my original guess that it is the Harmonic Balancer. How many miles do you have on your car? Go ahead and inspect all the other pulleys just to make sure nothing seems wrong with the others. These harmonic balancers do fail, it's actually pretty common to have a wobbling crank pulley. Mine wobbles which is why i had to purchase an ATI S.Dampner before installing the blower. The balancers go for 100 bucks used with low miles from a junk yard. I can give you the one off my car next week, however as i said it's wobbling as well.

Changing out these main pulleys are a PITA. I know you said this isn't a good time for you. But if there's anyway you can swing a used cam/pushrods/springs, I highly recomend you consider a cam swap while you're there.


Chris

 

Thanks!

Bump

 

Any suggestions?

 

I agree this sounds suspiciously like a problem I had after a CAM swap and it turned out to be the harmonic balancer. Have you had a CAM job?

 

No sir. The car has 102k miles on it though.

What was the outcome on your car. Did it do any damage?