Harmonic Dampener questions
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Harmonic Dampener questions
How do you know when they go bad?
Stay with GM part or is aftermarket OK?
When I removed mine yesterday the rubber was weatherd and cracking and in one spot the rubber had worked it's way out toward the front of the motor @ 3/4". But there was still rubber between the hub and the dampener. Is it time to replace this part?
I have taken a short video of the motor at idle so you can hear the noise the car is making. I can email this to anyone or if someone would be king enough to upload it to a website so others can access it readily.
TIA
[Modified by ld85, 9:21 AM 9/3/2002]
Stay with GM part or is aftermarket OK?
When I removed mine yesterday the rubber was weatherd and cracking and in one spot the rubber had worked it's way out toward the front of the motor @ 3/4". But there was still rubber between the hub and the dampener. Is it time to replace this part?
I have taken a short video of the motor at idle so you can hear the noise the car is making. I can email this to anyone or if someone would be king enough to upload it to a website so others can access it readily.
TIA
[Modified by ld85, 9:21 AM 9/3/2002]
Pro
Joined: Jun 2000
Posts: 686
Likes: 0
From: Crystal Lake, IL USA
Re: Harmonic Dampener questions (ld85)
I replaced mine this summer. The outside ring had moved back around the shaft enough that 13 degrees advance was being added to the base timing. The timing mark shifts the opposite of the engine rotation due to accessory drag. Running with a worn out AC compresser probably didn't help things a bit, although 100K miles seems to be the average service life on these.
At the same time it is moving around the shaft, mine was moving in toward the timing chain cover. This was visible from the front - the whole balancer assembly should be flush - my outside ring had moved 1/4 to 1/2" back. A good time to change it out is before it contacts the timing cover.
Once the balancer was off, I found about 1/2" play in the timing chain, so that got replaced at the same time. I went with original GM from Jeff Kopp on everything.
At the same time it is moving around the shaft, mine was moving in toward the timing chain cover. This was visible from the front - the whole balancer assembly should be flush - my outside ring had moved 1/4 to 1/2" back. A good time to change it out is before it contacts the timing cover.
Once the balancer was off, I found about 1/2" play in the timing chain, so that got replaced at the same time. I went with original GM from Jeff Kopp on everything.
Thread Starter
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Re: Harmonic Dampener questions (corvette0096)
I'll pull the balancer tonight. I cant rememeber how it was postioned on the hub but the cracking, weatherd rubber dosent look good any way. I am still goiing look in theouil pan just for saftey's sake. I will order the balancer from TLD today. :smash:
Also yesterday when I repalced the Timing Gear and chain, I was impressed that everything the gears were in really good shape. The mileage on the car obviously have been easy miles at 70K.
Also yesterday when I repalced the Timing Gear and chain, I was impressed that everything the gears were in really good shape. The mileage on the car obviously have been easy miles at 70K.
Drifting
Joined: Feb 2000
Posts: 1,994
Likes: 0
From: Charleston, WV
Re: Harmonic Dampener questions (ld85)
yup ......chuck it........ when mine went I was going past 4 grand and heard a loud POP!!! then I got home I saw an oil leak when I got out of the car that followed me to the garage........ what I didn't realize was the oil leak was the P/S rack on the end leaking .........I got under the car and found that the back of the balancer was shiny........I could see it from underneath so I looked on top and sure enough the balancer had slid apart ......that was what popped........... didn't vibrate though ............ :seeya
