Another wobbly Harmonic Balancer

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Dec 22, 2011 | 02:42 PM

BeetleBailey

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Another wobbly Harmonic Balancer

My 06 Coupe with 20,000 miles has the wobbly harmonic balancer.

Took it to the dealer for warranty repair (I have GMPP).
Service man says although it does have some wobble it's not bad enough to replace "yet".
Said we'd have to wait for it to get worse.

Mine is JUST like this one on youtube:

http://www.youtube.com/watch?v=XrYo7...ature=youtu.be

Looks like about 125 thousandths to me. (about 1/8th inch runout.

The bolt is tight and it doesn't look like the balancer has moved, it's just the outer ring (inner ring that attaches to the crankshaft is running true) that is wobbling.

I'm very concerned about it and feel as if it is ADDING vibration back thru the crankshaft instead of absorbing them.

Very dissapointed they won't change it.

What do you guys think I should do?

Last edited by BeetleBailey; Dec 22, 2011 at 02:44 PM.

Dec 22, 2011 | 02:59 PM

taken19

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Joined: Jun 2007

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From: Orlando Area

Tech Contributor

Talk to their service manager and tell him the potential consequence and their liability if they DON'T change it. It would be a much more expensive repair if it let go...

Dec 22, 2011 | 04:18 PM

BeetleBailey

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Quote:

Originally Posted by taken19

Talk to their service manager and tell him the potential consequence and their liability if they DON'T change it. It would be a much more expensive repair if it let go...

I'm, looking here on the forum for the factory spec. on runout.
There is also a procedure here on the forum for testing the runout (dial indicator against the pulley rear most rib, turn the engine by hand and measure it. After removing the spark plugs , etc, etc.

I have a dial indicator and can check it myself.

Anyone know the max. acceptable runout specification ?

Anyone have a link to the thread with all that information on checking and replacing the HB ?

Thanks in advance, guys.

Dec 22, 2011 | 04:29 PM

DSOMC6

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Joined: Dec 2005

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From: God's Country, ID

It wont harm the engine just having some runout...well unless it lets go..then it could do some damage. I'd keep the documentation from the dealer showing you did advise them of the issue.

Dec 22, 2011 | 04:38 PM

8850

Melting Slicks

Joined: Feb 2004

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From: Sugar Land TX

That's not .125 (1/8") runout. Probably not more than about .010. That amount is acceptable.

Dec 24, 2011 | 11:29 AM

swvalleyguy

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Joined: Aug 2011

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From: Huntington Beach CA

with 8850. The one shown in video doesn't have a horrible amount of runout. I would guess it would run another 200k miles and wouldn't lose too much sleep. But if you are the kind of person who likes to be safe its a simple matter of using dial indicator to get baseline measurement and then check in say, another 5K miles and note any change.

However, the balancer is really a dynamic device and the runout you would measure using dial indicator would be different when running. The optical/visual method of comparing runout to a known size of gauge might be the best approach and you could play the video frame by frame and compare movement with gauge size. This is low $$ approach.

Last edited by swvalleyguy; Dec 24, 2011 at 11:39 AM. Reason: Dynamic issue