C6 Harmonic Balancer issues
Thread Starter
Instructor
Joined: Oct 2013
Posts: 208
Likes: 4
C6 Harmonic Balancer issues
I've seen the results of high age / mileage harmonic balancer failure on youtube. My 2011 G.S. / 6M occasionally sees 7K rpm. At what age/mileage should I consider A Summit pulley & crankshaft pin kit ? Has anyone had a balancer go out/ wobble or vibrate on their daily driver?
thank you
thank you
Burning Brakes
Joined: Aug 2014
Posts: 1,240
Likes: 258
From: Tampa FL
Replaced Damper at 16000 mi on om 11 G.S. was wobbling and noisy. Replaced it with ATI and Rpm Bolt and pinned it. As far as pinning goes there are two kits. I pinned horizontally as to perpendicular to crankshaft. Now if I need to remove damper I will have to re-drill crank.
Will never be able to align crank and damper back up to use same hole.
If you drill perpendicular you use the key way and slide damper onto crank like old school. then if it needs to be removed slide it off and back on using keyway.
(SHOW/TELL) .............. Might not be for your engine !!!!!!!!!!!!
https://www.summitracing.com/parts/a...RoCrH4QAvD_BwE
Will never be able to align crank and damper back up to use same hole.
If you drill perpendicular you use the key way and slide damper onto crank like old school. then if it needs to be removed slide it off and back on using keyway.
(SHOW/TELL) .............. Might not be for your engine !!!!!!!!!!!!
https://www.summitracing.com/parts/a...RoCrH4QAvD_BwE
Burning Brakes
Joined: Aug 2014
Posts: 1,240
Likes: 258
From: Tampa FL
That's why I went aftermarket damper, I just choose ATI. The OEM bolt is torque to yield (one time bolt) And a special torque sequence.
I choose ARP crank /damper bolt and used their torque values
The problem seems to be the damper itself (poor design/materials) GM did not correct and we have trouble with them. Engines for many,,,,many years had a keyway in crank and damper. Even if the crank bolt loosened up the damper could still not spin on crank and chew it up.
With LS engines there is no keyway or key, aftermarket dampers still have a keyway for the most part
Most people think if your going for more power SC//TC you need to pin crank. I was there with the damper and it seemed the thing to do! Never like to repeat my self, when it can be done in the first place and be done with it.
Luck
I choose ARP crank /damper bolt and used their torque values
The problem seems to be the damper itself (poor design/materials) GM did not correct and we have trouble with them. Engines for many,,,,many years had a keyway in crank and damper. Even if the crank bolt loosened up the damper could still not spin on crank and chew it up.
With LS engines there is no keyway or key, aftermarket dampers still have a keyway for the most part
Most people think if your going for more power SC//TC you need to pin crank. I was there with the damper and it seemed the thing to do! Never like to repeat my self, when it can be done in the first place and be done with it.
Luck
Melting Slicks
Joined: Nov 2011
Posts: 3,183
Likes: 265
From: Virginia
I don’t necessarily think it’s relative to the mileage because I’ve seen ppl have failures with low medium and high mileage cars. Main thing is to keep and eye on it and watch for wobbling and listen for squeaking, at the point you need to change it. This happens to daily driver easy driven bone stock cars not just cars that are driven hard
Last edited by bwill03z; Jan 30, 2021 at 10:04 PM.
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Joined: Jul 2020
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Drifting
Joined: Feb 2003
Posts: 1,614
Likes: 163
From: Davis CA
Unless you are running a supercharger belt, a key or pin isn’t needed, right? The separation isn’t at the shaft as I understand it and we no longer have timing marks on the balancer - the reason for keys in the first place.
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,685
From: Southeast TX
An M6 Grandsport takes a different balancer vs a GS with an auto tranny. Manual GS takes the same balancer as a Z06. I've never had a problem with a Power Bond balancer. If you want to spend more money, there are other options. I agree with above saying there's absolutely no need to pin it unless you're running a belt driven supercharger.
Le Mans Master
Joined: Dec 2005
Posts: 6,999
Likes: 1,685
From: Southeast TX
Try this one. PowerBond PB1503SS PowerBond Race Performance Harmonic Balancers | Summit Racing I would call Summit's tech line and make DAMN sure. Their description could possibly be a little more confusing....naaaaaaa, it couldn't be any less clear.