Harmonic Balancer Issues
Thread Starter
Instructor
Joined: May 2010
Posts: 212
Likes: 12
Harmonic Balancer Issues
I took my 2007 in to have the harmonic balancer replaced along with the belts. It cost a bundle since the steering rack is in the way. At any rate, when I got the car back and drove it for a week I started to get a lot of squeal from the belts on startup. I took the car back to the shop and they told me it was the alternator and idler pulleys so they replaced those. As soon as I started the car the squealing was still there. I was a bit upset, to put it mildly and they immediately refunded my money ($671) and put my old parts back on. I lived with the noise until I decided to poke around a bit and I discovered that the harmonic balancer bolt was LOOSE. These are supposed to be TTY bolts so obviously no one had tightened it down. The car has been driven about 500 miles with this condition.
My questions: Has this oversight likely caused damage to the crank bearings? Would this loose pulley cause damage to the serpentine belt such that it would start to squeal?
Needless to say I am livid with anger over what they did to my baby. I'm not above demanding they put in a new replacement engine though I seriously doubt that's going to happen. I don't trust them to fix what's wrong and will need to have the entire procedure done again to be able to torque down the bolt.
My questions: Has this oversight likely caused damage to the crank bearings? Would this loose pulley cause damage to the serpentine belt such that it would start to squeal?
Needless to say I am livid with anger over what they did to my baby. I'm not above demanding they put in a new replacement engine though I seriously doubt that's going to happen. I don't trust them to fix what's wrong and will need to have the entire procedure done again to be able to torque down the bolt.
Le Mans Master
Joined: Dec 2004
Posts: 5,492
Likes: 808
From: West coast CA
I took my 2007 in to have the harmonic balancer replaced along with the belts. It cost a bundle since the steering rack is in the way. At any rate, when I got the car back and drove it for a week I started to get a lot of squeal from the belts on startup. I took the car back to the shop and they told me it was the alternator and idler pulleys so they replaced those. As soon as I started the car the squealing was still there. I was a bit upset, to put it mildly and they immediately refunded my money ($671) and put my old parts back on. I lived with the noise until I decided to poke around a bit and I discovered that the harmonic balancer bolt was LOOSE. These are supposed to be TTY bolts so obviously no one had tightened it down. The car has been driven about 500 miles with this condition.
My questions: Has this oversight likely caused damage to the crank bearings? Would this loose pulley cause damage to the serpentine belt such that it would start to squeal?
Needless to say I am livid with anger over what they did to my baby. I'm not above demanding they put in a new replacement engine though I seriously doubt that's going to happen. I don't trust them to fix what's wrong and will need to have the entire procedure done again to be able to torque down the bolt.
My questions: Has this oversight likely caused damage to the crank bearings? Would this loose pulley cause damage to the serpentine belt such that it would start to squeal?
Needless to say I am livid with anger over what they did to my baby. I'm not above demanding they put in a new replacement engine though I seriously doubt that's going to happen. I don't trust them to fix what's wrong and will need to have the entire procedure done again to be able to torque down the bolt.
Safety Car
Joined: Aug 2017
Posts: 4,924
Likes: 2,334
From: Etobicoke (Toronto) Ontario
There is a TSB about the bolt coming loose and the HB spinning on the crank snout. I don’t want to attach it because GMs electronic system might have a more recent and less work intensive version. But what the TSB does say to check is if the crank snout got galled, or metal from the HB got deposited in the snout. Sounds like the HB shouldn’t get reused in any case and the TSB did state that if there was enough damage to the snout then the crank would need to be replaced. There was no mention of any bearing damage and I don’t see why that would happen.
Installing the HB is a two step process. You use the old bolt and torque it to a specific value. Then you use the new bolt and complete the torquing by one of two methods depending on whether or not it’s an ARP bolt. If course there’s a lot of other work and steps involved. There’s a few write ups on the forum that pretty much follow the TSB.
You’re not the first to have the bolt back out and the balancer spin on the snout. But the problem is whether or not you’d trust the shop to make things right because sounds like you don’t. Did you talk to them? Can you get your money back?
Installing the HB is a two step process. You use the old bolt and torque it to a specific value. Then you use the new bolt and complete the torquing by one of two methods depending on whether or not it’s an ARP bolt. If course there’s a lot of other work and steps involved. There’s a few write ups on the forum that pretty much follow the TSB.
You’re not the first to have the bolt back out and the balancer spin on the snout. But the problem is whether or not you’d trust the shop to make things right because sounds like you don’t. Did you talk to them? Can you get your money back?
Drifting
Joined: Apr 2021
Posts: 1,934
Likes: 1,126
From: Peoria, AZ
2023 C6 of the Year Finalist - Modified
I had to pin the crank on my car with the install of the A & A S/C.......torques to spec myself, so I KNOW it's torques properly. I would go right back to the installer and tell them they need to redo the job that THEY didn't do properly IF you are so inclined to do, or get your money back and take it somewhere els with a good recommendation. There is absolutely no excuse for what they didn't do properly with torquing the bolt properly. Good luck!!
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Safety Car
Joined: May 2016
Posts: 4,654
Likes: 1,837
From: Erlanger, Kentucky
Why bother going back to the same shop that did **** work on your car? They will likely just mess up more stuff or jerk you around.
Take your car somewhere else.
Or do the job yourself. It really is not difficult, just a bit of work. All the info you need is here in the forums and plenty of people here who can help.
Take your car somewhere else.
Or do the job yourself. It really is not difficult, just a bit of work. All the info you need is here in the forums and plenty of people here who can help.
Pro
Joined: Jun 2021
Posts: 501
Likes: 40
From: SW Florida
ccrvtt, what part of the country are you in? Oddly enough, I just found out that my 2005 C6 harmonic balancer needs to be replaced. It apparently slipped forward causing my AC belt to come off. It is in a shop in SW Florida now getting the work done.
Here is a link where they talk about the C6 Harmonic Balancer:
https://legendaryfl.com/blog/corvett...r-common-issue
Here is a link where they talk about the C6 Harmonic Balancer:
https://legendaryfl.com/blog/corvett...r-common-issue
Safety Car
Joined: Aug 2017
Posts: 4,924
Likes: 2,334
From: Etobicoke (Toronto) Ontario
ccrvtt, what part of the country are you in? Oddly enough, I just found out that my 2005 C6 harmonic balancer needs to be replaced. It apparently slipped forward causing my AC belt to come off. It is in a shop in SW Florida now getting the work done.
Here is a link where they talk about the C6 Harmonic Balancer:
https://legendaryfl.com/blog/corvett...r-common-issue
Here is a link where they talk about the C6 Harmonic Balancer:
https://legendaryfl.com/blog/corvett...r-common-issue
Pro
Joined: Jun 2021
Posts: 501
Likes: 40
From: SW Florida
Two completely different problems. ccrvtt's balancer is loose on the crankshaft because it was installed incorrectly. In your case it looks like the outer half of the balancer has separated and walked forward because the rubber insulator failed. Presumably, the inner half of your balancer is still tightly secured to the crankshaft, so there's no danger the snout is damaged. It's true your balancer needs to be replaced and according to the TSB, so should ccrvtt's.
1. Asking what part of the country the person is in, because of the shop whose link I posted that knows the "right" way to do this repair
2. To add relevant information to the discussion
Right now I am awaiting the shops report as to how extensive a repair is needed. The issue began on Sunday (6/25) when suddenly my AC started blowing how. I posted this in a separate discussion in this forum and, based on suggestions, checked and found the AC belt was off. Further visual inspection and saw it looked like the balancer had moved forward. There was a lot of noise when driving, especially when braking, so I took it to the shop whose link I posted.
https://www.corvetteforum.com/forums...owing-hot.html
I hope ccrvtt gets the correct repair and his money refunded for the shoddy work.
Thread Starter
Instructor
Joined: May 2010
Posts: 212
Likes: 12
Update on Friday: Took the car back to the shop on a roll back (that's a painful sight, believe me) and expressed my concern to the owner. To his credit he was very patient and understanding. They have had the car for a day and a half now and have not updated me on the progress. I know that they'll have to disassemble everything to fix it. If the part is defective they can take it back to wherever they bought it and file a labor claim. The success of that is going to depend on how good their relationship is with the parts supplier.
At this point I'm beginning to question my unhealthy emotional attachment to a car. But then I remind myself, "It's a Corvette, this is perfectly normal."
At this point I'm beginning to question my unhealthy emotional attachment to a car. But then I remind myself, "It's a Corvette, this is perfectly normal."
Pro
Joined: Feb 2021
Posts: 729
Likes: 317
From: Ashevile, NC
OP you don't say what brand of balancer you bought or if you had an ARP bolt installed. I wouldn't trust any balancer (particularly an OEM) other than an ATI or a PowerBond. The ARP bolt is essential, again never re-use the original or even a new GM bolt. Proper torque specs is extremely important. All this being done properly you shouldn't have any issues. Best of luck.
Safety Car
Joined: May 2016
Posts: 4,654
Likes: 1,837
From: Erlanger, Kentucky
Update on Friday: Took the car back to the shop on a roll back (that's a painful sight, believe me) and expressed my concern to the owner. To his credit he was very patient and understanding. They have had the car for a day and a half now and have not updated me on the progress. I know that they'll have to disassemble everything to fix it. If the part is defective they can take it back to wherever they bought it and file a labor claim. The success of that is going to depend on how good their relationship is with the parts supplier.
At this point I'm beginning to question my unhealthy emotional attachment to a car. But then I remind myself, "It's a Corvette, this is perfectly normal."
At this point I'm beginning to question my unhealthy emotional attachment to a car. But then I remind myself, "It's a Corvette, this is perfectly normal."
Anyway, I hope the show does right.
Thread Starter
Instructor
Joined: May 2010
Posts: 212
Likes: 12
Got the car back yesterday. No squealing belts yet. Having run the gamut of emotions regarding the car, the shop, feelings for my wife, kids and grandson I'm a bit spent. 'Papas blue car' is resting serenely in the garage right now. It's going to get treated to some cleaning and a coat of Meguiar's Ultimate over the 4th of July weekend.
Being in the parts business I've come in contact with a lot of shops and I understand things can go wrong. The vast majority of shops don't want to screw up and have comebacks. Reputation is everything in small businesses. I'm not the kind to write scathing reviews for Yelp and I won't do it in this case. I once heard an industry executive say that we take the brightest kids and send them to college to be doctors then those of us left over go into other fields like retail and auto mechanics. After over 70 years in this vale of toil and sin I've come to understand that more than a few doctors make bad diagnoses as do some technicians. But anyone who's really good at what they do will have a job forever.
Being in the parts business I've come in contact with a lot of shops and I understand things can go wrong. The vast majority of shops don't want to screw up and have comebacks. Reputation is everything in small businesses. I'm not the kind to write scathing reviews for Yelp and I won't do it in this case. I once heard an industry executive say that we take the brightest kids and send them to college to be doctors then those of us left over go into other fields like retail and auto mechanics. After over 70 years in this vale of toil and sin I've come to understand that more than a few doctors make bad diagnoses as do some technicians. But anyone who's really good at what they do will have a job forever.
Team Owner
Joined: Sep 2002
Posts: 30,459
Likes: 4,592
From: Bonita Springs, Florida
Sounds like the crank bolt wasn't torqued to spec. Hopefully two's a charm.
Was an OEM balancer and bolt installed or did you go with an ATI, Summit or Powerbond Balancer and an ARP bolt? Either way hope it was done properly.
We're all attached to our Corvettes.
Was an OEM balancer and bolt installed or did you go with an ATI, Summit or Powerbond Balancer and an ARP bolt? Either way hope it was done properly.
We're all attached to our Corvettes.
Pro
Joined: Jun 2021
Posts: 501
Likes: 40
From: SW Florida
My 2005 C6 is still in the shop waiting for the Harmonic Balancer to be replaced. It slipped forward causing my AC belt to come off and the serpentine belt to shift.
The shop is planning to use a Dorman harmonic balancer for the repair. Does anyone know if that is a good choice? The work is supposed to start on Monday, 7/3.
The shop is planning to use a Dorman harmonic balancer for the repair. Does anyone know if that is a good choice? The work is supposed to start on Monday, 7/3.