need-for-speed

I know it's cuz it's a POS GM balancer and many of them eventually fail by the outer ring slipping at the bond with the inner hub.

But I'm curious as to what specifically makes the ringing noise on cold startup. Is it a slight belt misalignment? There is no visible wobble (well, at least to my crappy 58 y.o. Eyes) and the noise goes away after about 10 seconds...............

WW7

If you don't have a noticable amount of wobble and your getting noise , it's probably one of 3 pulleys on the motor that is in need of grease...I had a squeal at startup that lasted about a minite or less and it turned out to be the top idler pulley was void of grease..Repacked the bearings and the noise was gone...Get a stethoscope and see if you can't pinpoint the pulley that's making the noise..WW
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CMY SIX

very few of them failed for that reason and was pretty much 2005 only, the majority of the rest of them where changed by owners listening to other owners who didn't have a clue as to what a HB does or how it operates, a stock HB on ANY makes of car DOES NOT run straight and true and only looks worse over time, ATI became millionaires off the uninformed

Dcasole

Really , you going to tell me my 2011 did not have a bad balancer ... it was wobbling so bad that when the service writer looked at it his exact words were " boy that's not good"

And where do you get off saying any make does not run true , I have had may cars and boats from small blocks to twin supercharged fat blocks and I never , never saw a harmonic balancer on any of them wobble

Yet in my two years in the corvette comunity I have seen more bad harmonic balancers than in my whole automotive career

Dave

need-for-speed

Thanks WW. How did you pack the bearings? Are they serviceable?

need-for-speed

I think it's unacceptable to have such a design. However, I wonder how many people know that it's nothing new. Even with old school SBC (and the keyed crank & balancer) it was not uncommon to have the balancer separate. The outer disk moves toward the engine and eventually cuts into the timing chain cover. I've replaced many of them.

The only difference is that we didn't have the internet so everyone thought theirs was a unique failure.

Dcasole

Yes I agree I have seen them come apart at the track. but the failures were few and far between and we spent a lot of years at the track
But the design on the LS motors is by far the worse ......

And you are right , the Internet helps .....

walleyejack

walleyejack

people are so far out to lunch on this, how many c6 s were sold ? how many had a make believe bad balancer ? 1 % maybe. people have one issue and it is the end of the world, between this balancer and the 427 s valves, unbelievable. some folks will fall for anything, oh i need a new balacner it will destroy my engine, lol.. too funny

walleyejack

why would you buy a car that is made with a pos then ? you better stick to Prius.

need-for-speed

GFY SFB puzzy.

I've been driving and building hi performance Chevrolets since you were shytting in your pants vagina boi.

WW7

Yes, they can all be repacked with a high speed high temp grease.. The 3 pulleys I repacked were the top idler pulley, the AC idler pully, and the small metel covered drum pulley next to the crank pulley...On all three of these you can pull the side covers off to get to the bearings.. I use a small pick tool to get the side covers off..Then you just flush them with brake cleaner , let them dry or blow them dry with compressed air, then repack them with grease and reinstall the side covers...You can get these pulleys new ,but as long as the bearings are ok repacking them is fine......WW

BlindSpot

Agree - I've done the same on several cars. Easier and faster than replacing.

At the risk of starting another whacky 136 post thread on "planned obsolescence", these bearings are woefully under lubed in manufacturing.

WW7

If you don't think it's the pulley bearings causing the noise, you can try installing a Gatorback serpentine belt instead of the stock belt..These belts have solved quite a few high pitched squeals in these cars when the owners can't get anything else to work...WW
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B-Vette

The ringing noise might be the idler pulley, I'd have it checked. Usually the tell tale sign of the balancer going is belt chirp and a very noticeable wobble on the harmonic balancer.

walleyejack

But a genius like yourself, that has suppossedly building high-performance Chevrolets for a couple of years would know what the ringing noise is. Actually that ringing noise is between your ears probably

EVRose

Why would it be 2005 only when the same part was used throughout the entire C6 run? You're confusing this with the problem the few 05's had with the crank bolt coming loose. Two separate issues.

Bruze

The latest issue of Corvette Magazine has an article about buying C6s and the common problems to look for.

There was no mention of harmonic balancers.

EVRose

Well there should have been. It is not an imaginary issue.

windyC6

HUH...well we'll pawn this one off as just a bad night. Just to be sure that we all have a "clue". Most balancers run straight and true on most vehicles. Now of course straight and true is relative. Straight and true means that the balancer has no concern able wobble. You could pop the hood on thousands of different cars and the balancer will have no concern able wobble. You pop the hood on thousands of C-6 Corvettes, and the chances are there WILL be a concern able wobble on some/maybe most of them. So to suggest that anyone who got a new balancer cause theirs had a significant wobble is "Clueless".....well thats just "Clueless"......