Harmonic balancer problems
Thread Starter
Le Mans Master
Joined: Oct 2012
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From: South Dakota
Harmonic balancer problems
I'm curious how many C6's actually have HB issues at some point. How common is it? Some of those that have the issue post the problem on CF, but I'm wondering if the number of C6's that truly have the problem is actually a very small percentage. I have had ~25 company cars during my career, as well as many personal vehicles, and I have never had a HB problem. In fact, I never heard of HB problems until I became a regular on CF three years ago. Are HB problems unique to vettes?
Team Owner
Joined: Mar 2014
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From: Below the bottom of Berby Hollow, NYS
I'm curious how many C6's actually have HB issues at some point. How common is it? Some of those that have the issue post the problem on CF, but I'm wondering if the number of C6's that truly have the problem is actually a very small percentage. I have had ~25 company cars during my career, as well as many personal vehicles, and I have never had a HB problem. In fact, I never heard of HB problems until I became a regular on CF three years ago. Are HB problems unique to vettes?
I bought my first car in 1966, with many junkers to follow, and I've NEVER had a problem with them, nor did any of my gearhead buddies I hung around with.
My C6 has 27k miles, so far so good.
Tolero Apto Victum
Joined: Jul 2007
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From: Woodlands TX
OP: Here is one of many threads on the OEM Harmonic Balancer issue - https://www.corvetteforum.com/forums...lure-poll.html
I did have a problem and had the OEM unit replaced with an ATI unit, no problem as of yet with the ATI unit.
I did have a problem and had the OEM unit replaced with an ATI unit, no problem as of yet with the ATI unit.
Safety Car
Joined: Jul 2009
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From: Baton Rouge LA
St. Jude Donor '14, '16
Happens to many and is not unique to vettes. You only hear of cars with problems though, so the internet will make you think it is way more prevalent than it is.
I replaced one at 44k on one car, and 4500 on the other.
I replaced one at 44k on one car, and 4500 on the other.
Safety Car
Joined: Jan 2011
Posts: 4,959
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I'm curious how many C6's actually have HB issues at some point. How common is it? Some of those that have the issue post the problem on CF, but I'm wondering if the number of C6's that truly have the problem is actually a very small percentage. I have had ~25 company cars during my career, as well as many personal vehicles, and I have never had a HB problem. In fact, I never heard of HB problems until I became a regular on CF three years ago. Are HB problems unique to vettes?
Safety Car
Joined: Jan 2011
Posts: 4,959
Likes: 526
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Team Owner
Joined: Mar 2014
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From: Below the bottom of Berby Hollow, NYS
The forum dwellers that say its a very small percentage aren't comparing the problem to the "Normal" performance of a harmonic balancer. If you were to take every HB ever made in the world who knows what the % of failure would be. Probably something around .001 %. And out of those probably 50% would be from C-6 Corvettes.....LOL. Bottom line is that even a 20% failure rate for an HB is way to high.....and the C-6 is probably greater than 20%. Now before all the dwellers out there start screaming that 20% is way to high.....lets not forget that there are probably many C-6 owners that don't even know they have a bad one. All this of course is stated...."In my opinion".....lOLOL.
Hey windy, I was hoping you'd show up here.
Safety Car
Joined: Jul 2009
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From: Baton Rouge LA
St. Jude Donor '14, '16
Tolero Apto Victum
Joined: Jul 2007
Posts: 9,669
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From: Woodlands TX
Safety Car
Joined: Jan 2011
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Back at cha there Bruze. As old as these balancer threads are getting...I just can't seem to keep from throwing in my 2-cents worth. I guess it takes old experianced farts...(OOPS...sorry about the S on fart....don't want to speak for you)...to understand the problem. Heres something interesting I found out. Some/most places (around these parts at least) won't consider doing a "Tune" if you have a bad/wobbling HB. Their concerns are that the thing could come apart while on the dyno at high RPM's. I guess I can see their point. An HB coming apart at 6000-7000 RPM could be somewhat...."Disturbing", to say the least.
Race Director
Joined: Sep 2009
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From: Eastern
I have over 75K miles on my 2006, and no issues so far.Like someone has mentioned, we only hear about the ones that have had problems.
Not too many come on just to say, my car's HB is OK at xx miles.
Team Owner
Joined: Mar 2014
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From: Below the bottom of Berby Hollow, NYS
Back at cha there Bruze. As old as these balancer threads are getting...I just can't seem to keep from throwing in my 2-cents worth. I guess it takes old experianced farts...(OOPS...sorry about the S on fart....don't want to speak for you)...to understand the problem. Heres something interesting I found out. Some/most places (around these parts at least) won't consider doing a "Tune" if you have a bad/wobbling HB. Their concerns are that the thing could come apart while on the dyno at high RPM's. I guess I can see their point. An HB coming apart at 6000-7000 RPM could be somewhat...."Disturbing", to say the least.
As I said in post #2, in the numerous junkers, hot rods, trucks, etc. I've had since I started driving in 1966 I've NEVER had a balancer problem -- nor did any of my buddies.
And to say, "I've got XX,XXX miles on my C6 and no HB issues -- therefore the 'problem' is way overblown" is an attempt to disprove a known problem with one anecdotal example. Worthless.
Le Mans Master
Joined: Feb 2014
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From: Chino CA
It has nothing to do with any particular production run or model year. Pinning the crank is not part the problem or a solution. It is a poor design of the actual balancer. The same design has been used on all LS2 and LS3 engines and the part was never re-worked through the entire C6 run. Search posts by Dano523 on the subject. He has posted detailed info on why the design has problems along with photos.
Safety Car
Joined: Jan 2011
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It has nothing to do with any particular production run or model year. Pinning the crank is not part the problem or a solution. It is a poor design of the actual balancer. The same design has been used on all LS2 and LS3 engines and the part was never re-worked through the entire C6 run. Search posts by Dano523 on the subject. He has posted detailed info on why the design has problems along with photos.
Team Owner
Joined: Mar 2014
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From: Below the bottom of Berby Hollow, NYS
Points well taken, but I find it hard to believe that GM...or any manufacture would have trouble with the design of such a simple part that has been relatively trouble free for years and years. I would tend to think that it would be geared more towards poor materials....poor manufacturing....unacceptable tolerances....etc...etc, or maybe a little of all these. But I guess it could be a little naive to think that the boys/girls at GM wouldn't sit back and say...."Hey, we've had no problems with our HB's for years, so lets try a new design and see what happens and lets put that new design primarily on our flagship car". and as always....in my opinion....LOL.
I can't think of all the GM vehicles I've had in my lifetime (which most of them were) but they run from the first being a 1961 Corvair and the last (excluding the C6) was a 1998 S-10.
NOT ONE ISSUE with harmonic balancers, but NOW they can't get them right? -- and, as you said, the problem is mostly on their flagship car?
I've also had several Fords, one Plymouth, and numerous J.a.p. trucks -- no HB issues.
Racer
Joined: Jun 2014
Posts: 278
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From: Phoenix area Arizona
I think the problem is the belt is driven off the outside of the ballancer. The older design had the belt driven off the inside of the ballancer & that put no stress on the rubber. The Vette has no room for a pulley on the front of the ballancer.