Harmonic balancer question.
Drifting
Joined: Sep 2012
Posts: 1,665
Likes: 789
From: Hernando MS
Put a white indicator mark inside to outside and check it every now and then to see if the HB has moved. Check it once a week or so.
If the mark does not stay in line you probably need to replace the HB.
I had it replaced on my 03 vert. Cost me around $500 parts and labor. I used the Powerbond HB with the ARP bolt.
I also changed out tensioners, idlers and belts. That cost extra.
Good luck!
If the mark does not stay in line you probably need to replace the HB.
I had it replaced on my 03 vert. Cost me around $500 parts and labor. I used the Powerbond HB with the ARP bolt.
I also changed out tensioners, idlers and belts. That cost extra.
Good luck!
The balancer in my '99 came apart (luckily) just a few hundred feet out of my driveway, it hadn't shown any of the tell tail signs of impending failure beforehand. I swapped it out with a Powerbond myself.
I've put a paint mark on my Z06's and keep an eye on it. Hopefully when it comes time it'll give me a little warning.
Instructor
Joined: Oct 2018
Posts: 113
Likes: 21
From: Phoenix, AZ
Wow, that is lucky. Precisely why I wanted to change mine out preemptively. I use my car for long road trips, and didn't want to be at the mercy of an unknown shop in another state.
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From: In a parallel universe. Currently own 2014 Stingray Coupe.
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Burning Brakes
Joined: Jun 2017
Posts: 1,045
Likes: 275
From: Wichita Falls Texas
Peace of mind about the vehicle you are driving is priceless.
The HB is a known problem in the C5. Fix it and move on is what works for me.
Do what you want, I always do.
Good luck!
Team Owner
Joined: Mar 2002
Posts: 24,160
Likes: 78
It's possible the wobble is just a visual effect of discoloration. Looking at mine, you'd swear it wobbles, but I can touch a stick to it while the motor idles and verify that there's no perceivable in-out movement.
Pro
Joined: Sep 2017
Posts: 675
Likes: 195
From: Green Oak Township, Michigan
Its not the center hub or bolt that is the issue..Its the sleeve on the rubber isolator that comes off. Through the years, the rubber deteriorates and the sleeve starts moving. How loose you let it get....is up to you. Cant make a horse drink water. Idle or off idle,, it probably wont do much. Throw the belt,,make a lot of racket,, scratch things up pretty good. 6K RPM is a whole different ball game. Could rip out your tensioners,,your Idler pullys..Go into your power steering pump..crack your timing chain cover...etc. and etc. You could get lucky and it will just come off and lay there. The choice is yours. At any rate, its a tow truck ride for your Corvette. In my opinion,,, its a waste of time painting lines on a wobbling balancer. Kinda' like playing Russian Roulette. If its not wobbling,,, dont worry about it. If it wobbles,, then just change the dam thing. If you do your own work,,it dont cost that much. Kinda like....I see that bulge in my tire,,,Ill just wait and see if it gets bigger.. Maybe Ill just paint a white line around it....
Instructor
Joined: Oct 2018
Posts: 113
Likes: 21
From: Phoenix, AZ
Its not the center hub or bolt that is the issue..Its the sleeve on the rubber isolator that comes off. Through the years, the rubber deteriorates and the sleeve starts moving. How loose you let it get....is up to you. Cant make a horse drink water. Idle or off idle,, it probably wont do much. Throw the belt,,make a lot of racket,, scratch things up pretty good. 6K RPM is a whole different ball game. Could rip out your tensioners,,your Idler pullys..Go into your power steering pump..crack your timing chain cover...etc. and etc. You could get lucky and it will just come off and lay there. The choice is yours. At any rate, its a tow truck ride for your Corvette. In my opinion,,, its a waste of time painting lines on a wobbling balancer. Kinda' like playing Russian Roulette. If its not wobbling,,, dont worry about it. If it wobbles,, then just change the dam thing. If you do your own work,,it dont cost that much. Kinda like....I see that bulge in my tire,,,Ill just wait and see if it gets bigger.. Maybe Ill just paint a white line around it....
Racer
Joined: Mar 2005
Posts: 275
Likes: 21
From: North Carolina
All GM C5 Harmonic Balancers are junk.
I have been through 3 Gm dealer installed harmonic balancers. All have failed. The last time one failed I was on a 200 mile trip and I by chance happened to check my oil and noticed that the Bolt that holds the balancer in had worked itself loose and was up against the steering rail. I found a Chevy dealership and took it to them, only about 2 miles, and they kept it and called me later in the day and said that it was fixed. What they did was tighten the original bolt and told me everying was fixed. They charged me close to 400.00 dollars! I got my vet home and went round and round with the dealer that installed the prior 3 balancers and finally they agreed to do the labor if I furnished the Bolt and Balancer. Best move I have made in a long time. I bought a ATI balancer from Summit Racing and an ARP Bolt. That was several years ago and my ATI and ARP bolt are still like new. No Wobble AT ALL. The ATI balancer runs at true as true can get and if I ever have a problem with Wobble you can rebuild the ATI and are good to go. I feel very good about the quality of Summit Racing's products and the ATI Balancer and ARP Bolt are as good as good gets.
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Racer
Joined: Mar 2005
Posts: 275
Likes: 21
From: North Carolina
https://www.summitracing.com/parts/a.../submodel/base
https://www.summitracing.com/parts/a...2503/overview/
ATI Super Damper Serpentine Series Harmonic Balancers 917266
https://www.summitracing.com/parts/a...2503/overview/
ARP Balancer Bolts 234-2503
Pro
Joined: Sep 2017
Posts: 675
Likes: 195
From: Green Oak Township, Michigan
A little cheaper,, but still SFI approved is the Powerbond/Dayco, PB1117N SS Race from Summit or Jegs at about $250 bucks. ATI is top quality., also Summit or Jegs.. Do it once,,,and forget about it. Summits phone number is 1-800-230-3030 24 hours a day... Jegs is 1-800-345-4545....
No Hostility Be Happy
Joined: Aug 2018
Posts: 10,079
Likes: 7,398
From: South Hill Wa
2022 C5 of the Year Finalist - Modified
2021 C5 of the Year Finalist - Modified
A little cheaper,, but still SFI approved is the Powerbond/Dayco, PB1117N SS Race from Summit or Jegs at about $250 bucks. ATI is top quality., also Summit or Jegs.. Do it once,,,and forget about it. Summits phone number is 1-800-230-3030 24 hours a day... Jegs is 1-800-345-4545....
Any of the SFI approved balancers even cheaper varieties are worlds better than any non SFI balancers of any brand including GM.
Instructor
Joined: Oct 2018
Posts: 113
Likes: 21
From: Phoenix, AZ
I have been through 3 Gm dealer installed harmonic balancers. All have failed. The last time one failed I was on a 200 mile trip and I by chance happened to check my oil and noticed that the Bolt that holds the balancer in had worked itself loose and was up against the steering rail. I found a Chevy dealership and took it to them, only about 2 miles, and they kept it and called me later in the day and said that it was fixed. What they did was tighten the original bolt and told me everying was fixed. They charged me close to 400.00 dollars! I got my vet home and went round and round with the dealer that installed the prior 3 balancers and finally they agreed to do the labor if I furnished the Bolt and Balancer. Best move I have made in a long time. I bought a ATI balancer from Summit Racing and an ARP Bolt. That was several years ago and my ATI and ARP bolt are still like new. No Wobble AT ALL. The ATI balancer runs at true as true can get and if I ever have a problem with Wobble you can rebuild the ATI and are good to go. I feel very good about the quality of Summit Racing's products and the ATI Balancer and ARP Bolt are as good as good gets.
Le Mans Master
Joined: Jul 2010
Posts: 6,671
Likes: 38
From: Newark DE
Racer
Joined: Jan 2018
Posts: 450
Likes: 165
The funny thing is how pathetic looking the stock balancer looks and feels when compared to an Innovators West Balancer. I can't wait to get the cam and balancer, etc... all in next week. One step closer to joining the high horsepower club with you guys.
Burning Brakes
Joined: Feb 2019
Posts: 1,028
Likes: 377
From: SW Ohio
Either powerbond option will be great for you - they are very reliable based on experiences here. I just did my own swap - and honestly it's pretty damn easy if your a guy who has worked on your own cars. Rent a balancer puller and 250 ft lb torque wrench from autozone / Oreilly Auto, and the parts are $200 ish. It took me about 6 hours total, and that was going very slow and being careful. Make sure you have flare nut wrenches for the power steering lines as well. Replace your front main seal while you have it off - I was shocked at how brittle my original seal was I took out.
If you don't replace it on your terms it will fail on it's own terms, which you can bet the farm that will be at most inconvenient time possible. It's sage advice everyone is giving you here to be honest.
If you don't replace it on your terms it will fail on it's own terms, which you can bet the farm that will be at most inconvenient time possible. It's sage advice everyone is giving you here to be honest.