Grzldvt

My 85 L98, I had a pretty serious grinding noise that I could not locate, several people on the Forum came to rescue and told me to check out the harmonic balancer. That was it :D
I thought I would post the outcome separately so others can see what happened and what I did. My removal is slightly different than the one Lars has in the Tech section, and potentially alot easier than modifying the puller center bolt.

Below are pictures of the old balancer (on the right) and the new balancer (on the left). You can see on the old where the outer rim has moved a good 3/4 of an inch, and where it's pulled away from the rubber.

I used a standard harmonic puller, rented at one of the local auto parts stores. The center bolt was just long enough be perfectly hidded by the crossmember. Using a standard socket I was able to get a few turns, but not much. A deep socket would force the ratchet into the sway bar and keep the socket from going on square. I finally used a 1/2" swivel head ratchet with a 4" inch extension. The extension pushed the handle into the fan housing, but I was able to position the fan blades out of the way and get leverage by reaching around the lower fan bracket. The swivel headed ratchet allowed the handle to be out of the way of the upper portion of the fan frame. I did not have to remove the fan. Ratchet movement was pretty restricted, it took a good 5 minutes of wrenching to pull it off.

It took a good 30 minutes of frustration, dropped tools just out of reach, and lots of nasty words to find this solution. So add that tip to your toolbox.
Here is the old balancer (on the left) and the new balancer (on the right)


Here is the back of the balancer, you can see where it was scraping against the timing chain cover. Marcho Polo has a similiar picture, that convinced me this was my problem. I could see the back of my balancer up against the timing chain cover.


I also found the reason for my shredded belt. The new alternator I installed has a subtley different pulley, which was not wide enough to hold the entire belt. It would ride up and get misailgned, which would force it off the next pulley as it would get forced off it would get cut by the pulley edges. Fortunately I still had the old alternator, so I was able to use the correct pulley.


[Modified by Grzldvt, 10:06 PM 1/19/2002]

Marcho Polo

Glad you got it fixed!!!! I know when mine was scraping, it was kind of a tough noise to diagnose at first.... I was at a track event with my dad and my uncle and we were standing over the car messing with it a good 30 minutes trying to narrow that noise, down! Seems to be a common thing though.

PurpleC4

Craig,
You guys should write a good procedure on how to diagnose and determine if this is a systemic problem that will occur in a lot of L98 generation Vettes. I can see where this could be a tough one to diagnose. Congrats to both of you.
:seeya Purp

BigTodd

This need to go into the Tech Tips Section of the Forum. Great Description and Pic's of the problem. I'm Gonna check my right now... :yesnod:

Grzldvt

Sounds like a good idea adding this to the Tech tips. Craig, you want to do it or do you want me?
Steve

Rick86

Seems like I'm also a victim of a slipped harmaonic balancer, my balancer wore a hole in the cam chain cover :mad still need to fix this problem, but car is on jacks awaiting a transmission rebuild