2002 C5 Z06 Harmonic Balancer Question
Thread Starter
Racer
Joined: Oct 2020
Posts: 305
Likes: 65
From: Huntington, NY
2002 C5 Z06 Harmonic Balancer Question
Hey,
I’m a new Z06 owner and am learning about the car as I go. Trying to address all the potential failure issues on my C5 Z06. Car has 37k miles.
My question is, if I install an ATI Harmonic Balancer do I still need to pin it to the crank? I’m not sure.
I know someone on the site has the answer!
I’m a new Z06 owner and am learning about the car as I go. Trying to address all the potential failure issues on my C5 Z06. Car has 37k miles.
My question is, if I install an ATI Harmonic Balancer do I still need to pin it to the crank? I’m not sure.
I know someone on the site has the answer!
Melting Slicks
Joined: Dec 2018
Posts: 2,663
Likes: 1,389
From: Orange County, CA
No need to pin the crank with the ATI, though you should fill the key slot with sealant/RTV to ensure no oil leaks. This is how I installed my ATI balancer on my '01 Z06 last year and it's been solid and leak-free since (knock on wood).
Safety Car
Joined: Mar 2017
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Stupid question, I, too am planning on a HB install. What oil will leak? The front main seal being intact, I am curious how an oil leak would occur through the keyway. Thanks.
Safety Car
Joined: Jun 2003
Posts: 4,510
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From: Coconut Creek FL
Not sure about the oil leak either, most people change the seal while in there. As for the crank pin, for the price and the effort and again, while you are in there, pin it. That way if you decide to add a blower later, one less major PITA to have to worry about doing. You can just slap on the super charger and not pull the rack out again. I had my balancer replaced on a 2000 coupe I owned, and while it was on the operating table, had them pin it just in case. I hope the new owner appreciated my extra efforts! LOL.
Melting Slicks
Joined: Dec 2018
Posts: 2,663
Likes: 1,389
From: Orange County, CA
But on the other hand, ARP doesn't say to use sealant under their bolt head (perhaps their lube also provides sufficient sealing properties?).
Here's a little diagram the internet helped me make. Orange is crank, dark gray is front crank seal, light gray is HB, green is bolt.
Also if you're the type of person who likes to read instructions, this is an excerpt from ATI's installation instructions, step 2:
If you are not using a key or pin, you must fill the key slot with some high temp silicone so no oil leaks past the
damper bolt washer!
http://www.atiracing.com/instruction...LS7-Damper.pdf
In addition, ATI's instructions say this about using sealant on the ARP bolt's washer:
Apply high temperature RTV to both sides of the washer prior to installation.
Last edited by MetalMan2; Jan 20, 2021 at 04:32 PM.
Pro
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Am I missing something here? There is no keyway on the LS1 or LS6 crankshafts. The balancer is just held on by a press fit. That is the reason why most guys replacing the balancer pin it to prevent it from ever slipping on the crankshaft.
Melting Slicks
Joined: Dec 2018
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From: Orange County, CA
That's the keyway in the ATI balancer.
Pro
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Drifting
Joined: Sep 2005
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From: Largo FL
My '03 Z is going to the shop to get an ATI balancer and ARP bolt done on Monday. They also recommended changing the oil seal while in there as cheap insurance since it would be a chore to get to later. You do need to move the steering rack out of the way to replace the balancer. I asked about pinning it and they said unless you're going to make significant power increases (turbo, supercharged, etc), pinning it isn't required.
Team Owner
Joined: May 2001
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From: Western NY
One other thing....the ATI balancer is "degreed", and by using the ATI pinning kit, you can get the balancer correctly positioned on the crank, so the degree markings are correctly oriented.