Harmonic Balancer, BIG issue or???
Thread Starter
Melting Slicks
Joined: May 2018
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From: Question Government
Harmonic Balancer, BIG issue or???
I'm thinking of selling my C4 and moving up to a 2003 or 2004 C5. The C4 guys have told me to watch out for failing harmonic balancers in the C5 engines. How common of an issue is this, and how hard is it to repair/replace for a qualified mechanic (not me)?
Team Owner
Joined: May 2001
Posts: 87,335
Likes: 1,590
From: Western NY
Due to the way the engine sits in a C5, low and rearward, access to the balancer is prevented by the steering rack, therefore a significant amount of disassembly is required to R&R it, Also again due to it's location, if it does "let go", the amount of damage it can cause could be considered significant. If it jumps forward, it'll tear up the steering rack. If it jumps rearward, it'll start to grind up the front cover of the engine.
Drifting
Joined: Mar 2017
Posts: 1,486
Likes: 343
From: Long Island New York
It will cost anywhere (average) from $650.00-$850.00 to do completely with parts installed depending on the shop.
If you are checking C5's out and notice a slight wobble, negotiate the price accordingly.
If you are checking C5's out and notice a slight wobble, negotiate the price accordingly.
Last edited by pjdbm; Dec 15, 2019 at 11:23 AM.
Burning Brakes
Joined: Jun 2017
Posts: 1,045
Likes: 275
From: Wichita Falls Texas
If you pick out a C5 that still has the factory balancer I would suggest you negotiate with them about getting it changed.
What I would do is try to get $1000 off the price and have your mechanic change out the balancer with a Powerbond and new tensioners and pulleys and belts.
I'm pretty sure a thousand will cover all that and then your front end of the engine would be good for many trouble free miles.
I had all that done to my 03 vert about a year and a half ago. I purchased all the parts and my mechanic installed them.
sure gives me peace of mind knowing that!
Good luck!
What I would do is try to get $1000 off the price and have your mechanic change out the balancer with a Powerbond and new tensioners and pulleys and belts.
I'm pretty sure a thousand will cover all that and then your front end of the engine would be good for many trouble free miles.
I had all that done to my 03 vert about a year and a half ago. I purchased all the parts and my mechanic installed them.
sure gives me peace of mind knowing that!
Good luck!
Last edited by Grandpa1; Dec 15, 2019 at 12:25 PM.
Melting Slicks
Joined: Mar 2018
Posts: 2,502
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From: California
It’s a easy install might take you a half a day. Yes the steering rack needs to be moved not entirely taken out. Besides that a alternator. And the radiator get moved forward. Water pump comes off. Power steering pump and abs junk comes off. I think just that’s about all I could be wrong. It’s really not a hard job. But it’s a good time to take care of any cam swaps or seals or timing to be done it’s all fairly cheap and if your down there you might as well change whatever you could.
Melting Slicks
Joined: Nov 2014
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From: Havre de Grace Maryland
Pro
Joined: Mar 2004
Posts: 714
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From: Springfield Ohio
Can't be done in half a day by a person that has not done at least one before and probably not by an experienced mechanic either. There is a lot of disassembly needed and there are a few connections and fittings that have to be finessed on removal and reassembly. You also need some special tools that most of us won't have. Tools can be borrowed or rented from many auto parts stores but they are sometimes not the best for the job. Anyone that can read and follow directions can do the job but plan a spending a couple of days doing it if you decide to do it yourself. There is a reason the repair is pricey at most shops - choose one that knows Corvettes. You generally get what you pay for!
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Team Owner
Joined: May 2001
Posts: 87,335
Likes: 1,590
From: Western NY
Can't be done in half a day by a person that has not done at least one before and probably not by an experienced mechanic either. There is a lot of disassembly needed and there are a few connections and fittings that have to be finessed on removal and reassembly. You also need some special tools that most of us won't have. Tools can be borrowed or rented from many auto parts stores but they are sometimes not the best for the job. Anyone that can read and follow directions can do the job but plan a spending a couple of days doing it if you decide to do it yourself. There is a reason the repair is pricey at most shops - choose one that knows Corvettes. You generally get what you pay for!
I swapped out the HB on my car, and will admit that I also got a bad case of "while I'm in there", which led me to also swap out the timing chain, for an LS2 chain, and also install a Trick Flow timing chain stabilizer. I'm retired, and my Corvette isn't my DD, so I didn't have to rush the job, but I didn't dawdle, either. Including the extra work I did, which also included "pining" the balancer hub, it took me about 24 hours, spread over 3 days.
In terms of "extra tools", I obtained a crankshaft locking tool, which butts up against the flywheel, to keep the crank in place, when you "torque up" the HB retaining bolt (an ARP piece) to 240 ft/lbs, a torque wrench, with a 250 ft/lb capability, as well as a front cover alignment tool. I've been a "backyard mechanic" for over 50 years, and in my honest opinion, this isn't a job for a "first timer"....
Melting Slicks
Joined: Mar 2018
Posts: 2,502
Likes: 187
From: California
Note to the op. I used the summit pulley puller and installer. Plus I have a pin tool from trick flow for my sfi 18.1 balancer stock size. I used the ls3 timing conversion with billet gears. I didn’t swap cam shafts didn’t see a need as of that time. Easy peezy.
most of my time spent was honestly waiting for parts to come in that were not really related to what I was doing like a original gm power steering tank rubber hose,and idler pulley. I tried using a cheap dorman which apparently doesn’t fit our car had to using the original part #! I do have a ls6 arp crank bolt I would let go cheap because arp sent me the wrong crank bolt and head studs. I sent the head studs back.
most of my time spent was honestly waiting for parts to come in that were not really related to what I was doing like a original gm power steering tank rubber hose,and idler pulley. I tried using a cheap dorman which apparently doesn’t fit our car had to using the original part #! I do have a ls6 arp crank bolt I would let go cheap because arp sent me the wrong crank bolt and head studs. I sent the head studs back.
Last edited by Speedy007; Dec 16, 2019 at 01:22 PM.
Intermediate
Joined: Aug 2013
Posts: 33
Likes: 5
From: Wake Forest, NC
I had mine done and was told that because the cradle was removed they had to do an alignment. I had mine done at the dealer and it was $1300 plus tax which included the balancer, bolt, crank seal, serpentine belt and A/C belt. The belts were $178. The alignment was $100. There was a $20 shipping charge.
Last edited by LuckyLou; Dec 16, 2019 at 06:43 PM.
Moderator
Joined: Jun 2004
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Ive done this in 4-5 hours, the only thing that needs to come out is the steering rack. Disconnect the tie rods, remove the front wheels, disconnect the hydraulic lines, secure the steering wheel with a bungee cord and disconnect the steering shaft from the rack.
With the rack out of the way the balancer is accessible without removing anything else. You can loosen the cradle bolts and drop the front cradle about an inch, that helps. Its not a big job but it is laborious
With the rack out of the way the balancer is accessible without removing anything else. You can loosen the cradle bolts and drop the front cradle about an inch, that helps. Its not a big job but it is laborious
Burning Brakes
Joined: Feb 2019
Posts: 1,028
Likes: 377
From: SW Ohio
Ive done this in 4-5 hours, the only thing that needs to come out is the steering rack. Disconnect the tie rods, remove the front wheels, disconnect the hydraulic lines, secure the steering wheel with a bungee cord and disconnect the steering shaft from the rack.
With the rack out of the way the balancer is accessible without removing anything else. You can loosen the cradle bolts and drop the front cradle about an inch, that helps. Its not a big job but it is laborious
With the rack out of the way the balancer is accessible without removing anything else. You can loosen the cradle bolts and drop the front cradle about an inch, that helps. Its not a big job but it is laborious
