1999corvettels1

I keep reading about balancer wobble on the C5 Corvettes, I don't think mine has it, but how would one know?

I was under it looking around and even with the engine running, seems ok.

Would it really look like a wheel missing lugnuts getting ready to come off car?

3sACROWD

The short answer is yes. The damper will have an easily identifiable wobble. As you look at the damper from the side and engine running, the damper will look like it is moving towards and away from the front of the car.

pjdbm

if you stare at the HB, it is pretty hard to miss, it should not be "dancing" at all.

In less than 50 days, I will be doing mine

Vetteman Jack

If your car has a balancer that is wobbling, you should be able to see it.

Eric Sr

My ac compressor would start squealing when under load that progressively got worse in the past few months. H. balancer had a good amount of wobble as well. Replaced both this past week... 93,000 miles

grampi50

Was either one expensive?

MikeG37

I had checked the balancer on my '99 after an oil change a few days before it failed, I didn't see any sign of wobble. It did have an occasional squeaky sound at cold startup that would go away pretty quick as it warmed up but I blamed that on one of the belts.. nope, that was my warning. Luckily I was only a few feet out of my driveway when it disassembled itself.

Lexybird

1:Turn car on
2:watch the harmonic balancer
3:any wobble is too much wobble
4: get your wallet out ..or call the boss and tell him your taking the next week off to tear your corvette apart

grampi50

So how expensive is it to have the HB replaced?

Lexybird

Well some guys have got lucky and got it done cheap at a local capable ma and pa garage for 5-600 . Some on here I have read have paid well over 1000$ at a dealership to have it done . By design You have to just about tear the whole front of your car off to get to it . including removing the rack and pinion .my guy charged me only 300$ which I was glad to pay but he is really cheap compared to most places

grampi50

Maybe I'm not quite sure about what a HB does/is, but to me, they just seem like a big, round chunk of metal, so I don't understand what goes wrong with them that they need to be replaced...

MikeG37

They're two pieces of steel with rubber isolator in between.. that's what fails. Suppose to look like this.



When they fail they look like this.



The outer ring would've flown out from under the car if my steering rack hadn't have stopped it.

grampi50

So are the new ones made differently so they won't fail, or are they exactly the same piece?

C6_Racer_X

Adding a bit to the symptoms (3). Also look for a serpentine belt that's not straight, or a belt that has slipped over one (or more) grooves on the HB, so that part of the HB pulley is visible that should be covered by the belt.

This is one part where you probably don't want "Genuine GM" parts. I think the "factory" part has been redesigned, but how trustworthy is that. They are the ones who designed the faulty one.

There are some "high performance" alternatives that might be better choices, especially if you drive your Corvette hard at times (autocross, track days, drag strip, even "spirited drives" on twisty roads).

STALION

I did mine, and it wasn't to expensive. Had to replace the AC pulley, and the balancer. After reading up on what was required I decided to go with an after market damper as the stock one from GM is known to be a "fail" point. Several on the market to choose from, I went with Powerbond PB1117N. It's good for a stock replacement and can also handle upgrades if you have them.

JohnRogers

I think that is what many of us noobs are really asking. Wondering if there was any wobble under correct factory conditions.

MikeG37

The Powerbond I replaced my broken OEM with looks to be made basically the same. I wouldn't be shocked if it isn't susceptible to the same problem 10-20 years in the future, my car had less than 25,000 mi on it when it let go but the rubber was ~17 years old.
If I'd read up/shopped a little more before I fixed mine I'd probably have spent the extra $ on an ATI.. that's what I'll eventually replace the Z06's with.

STALION

The powerbond is actually much better and stronger....

https://ls1tech.com/forums/cadillac-...-pictures.html

jjaaam

I've looked this very question up many times across the web...not just on this forum...

From what I have seen there are many that say ANY wobble is a sign of imminent failure and that the balancer needs to be replaced right away. Other sources I have seen say that a slight amount (~1/32" or so) is fairly common on LS1's.

I'm certainly not saying that one school of thought is right over another. Mine has a small amount of wobble, but it has had the same amount since I bought it three years ago @ 84K (now 106K). All I do is monitor it. I put some paint on it to see if the lines start to separate. If they do, then I have a repair coming in the near future. Granted, I may be risking an immediate and catastrophic failure, but from what I have seen wobble and belt squeal tends to get worse over a period of time and can act as a warning. Instantaneous failure is certainly a possibility but I haven't heard of that many instances of it.

Here is a post I found and commented on another thread. The statements in parentheses were my comments:

"Hi there, First, the prevelance of this condition is there.

Second, there is NO SPECIFICATION for runout on the c5 or c6 harmonic balancer. (This tells me that some wobble may be present. If zero wobble was required then there would HAVE to be some sort of spec, I would think)

Third, rubber isolated harmonic balancers are known to rotate at times in some applications.

The AC belt is usually the first one to make noise as it has the weakest tensioner.

Excessive runout in the balancer magnifies the noise when cold.

I have also installed BRAND NEW balancers that have had wobble. (From tolerances in the manufacturing process maybe?)

The key, is accurate tension of the belts and alignment with the other pulleys.

My rule of thumb is 1/32 inch runout maximum. (Granted, this is just this person's opinion, but again - there is no absolute SPEC.)

Allthebest, c4c5 GM World Class Certified Technician"

IMHO it's all about what you are comfortable with. Some may call me crazy but I'll risk the instantaneous failure in order to avoid shelling out $$$$ that I might really not have to do. YMMV.

Eric Sr

Roughly $1,000. each... I know the guy who owns the businesd so he cut me some breaks here n there.