Harmonic Balancer Installation
Thread Starter
Pro
Joined: May 2006
Posts: 583
Likes: 66
From: Fayetteville North Carolina
St. Jude Donor '17-'18
Harmonic Balancer Installation
Starting my install this weekend on my MN6 99 coupe. I have all the parts ordered and have gathered all the proper tools. I will be doing this on a 4 post lift. I have the service manuals in the 3 volume set. I have researched it on the forum for a couple of weeks. I will be sure to bungie/tie my steering wheel to keep it from turning. Any other tips or gotchas I should be aware of. Thanks for the help.
Mike
Mike
Drifting
Joined: May 2007
Posts: 1,547
Likes: 210
From: Huntersville, NC
It will take a lot of force to tighten the bolt. I used a 3/4 drive with a cheater pipe and another guy to help pull. If you can heat the center hub without damaging the rubber in the balancer that may help installation.
If you are just doing the harmonic balance, then all you have to do is move the steering rack.
if you get a piece of 16mm all thread and nuts, it will help with the install, instead of trying to find a longer bolt.
It the service manual there is a dimension for the distance from the end of the crank to the hub of the pulley. You need to get the harmonic balancer to that point with the old bolt then put the new one in. You always have to replace that bolt.
If you are just doing the harmonic balance, then all you have to do is move the steering rack.
if you get a piece of 16mm all thread and nuts, it will help with the install, instead of trying to find a longer bolt.
It the service manual there is a dimension for the distance from the end of the crank to the hub of the pulley. You need to get the harmonic balancer to that point with the old bolt then put the new one in. You always have to replace that bolt.
Melting Slicks
Joined: Nov 2013
Posts: 2,049
Likes: 316
From: USA
Some things I did for an easy seamless install:
-Put a dab of antiseize on the crank snout
-Put my new balancer in a big pot filled with water...put it on the stovetop until the water boiled. Pulled it out (with gloves of course) and did the install quickly before it had time to cool down much.
-I used the longer "LS7" bolt to get it started, then once it was threaded in all the way I pulled it out and pressed it on the rest of the way with ARP bolt.
-With all that done and my torque wrench is around 2 feet or longer, honestly I didn't find it all that hard to hit the torque spec.
-Put a dab of antiseize on the crank snout
-Put my new balancer in a big pot filled with water...put it on the stovetop until the water boiled. Pulled it out (with gloves of course) and did the install quickly before it had time to cool down much.
-I used the longer "LS7" bolt to get it started, then once it was threaded in all the way I pulled it out and pressed it on the rest of the way with ARP bolt.
-With all that done and my torque wrench is around 2 feet or longer, honestly I didn't find it all that hard to hit the torque spec.
Safety Car
Joined: Mar 2005
Posts: 3,757
Likes: 1,215
From: Wisconsin
Starting my install this weekend on my MN6 99 coupe. I have all the parts ordered and have gathered all the proper tools. I will be doing this on a 4 post lift. I have the service manuals in the 3 volume set. I have researched it on the forum for a couple of weeks. I will be sure to bungie/tie my steering wheel to keep it from turning. Any other tips or gotchas I should be aware of. Thanks for the help.
Mike
Mike
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Joined: Dec 2010
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2020 Corvette of the Year Finalist (performance mods)
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Thread Starter
Pro
Joined: May 2006
Posts: 583
Likes: 66
From: Fayetteville North Carolina
St. Jude Donor '17-'18
I will use the correct installation tool, not a bolt for installation. Thanks.
Melting Slicks
Joined: Feb 2001
Posts: 2,804
Likes: 358
From: Northville, MI
When I installed mine I used a new GM bolt, torqued it to 37 ft-lb then measured another 240 degrees and drew a line on the balancer with white paint stick. I had a 30 to 1 torque increase tool used for truck tires, wedged it to the frame and then used a standard 1/2 in torque wrench and gingerly turned it the last 240 degrees. I have helped to other friends install their new balancer as well and the hardest part was lining up the power steering threads when putting the steering rack back in.
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Race Director
Joined: Sep 2005
Posts: 11,060
Likes: 291
From: Pasco WA
I've had mine off three times to do various mods, and all that heating and special tool stuff is nonsense. Fastenal, and other tool stores have long bolts in stock threads that work great. Just get one about 125mm long. Another good idea is to pin the balancer to the crank, thus avoiding the possibility of the two ever separating again.
Burning Brakes
Joined: Aug 2010
Posts: 1,051
Likes: 54
From: Raleigh NC
The long rod is the simple, safest, and best way to do it if you have access. But most stores around here dont have them in stock. Or they want $30 for a 2 foot long rod.
I found it WAAAAAAY easier to just heat the pulley in the oven (never tried boiling lol) and then it just slides on the crank. A couple light taps with a rubber mallet and you have enough of the pulley on the crank that you dont have to worry about stripping the threads. Then just instal.
People also like to complain about removing the steering rack. Its take me about 15 minutes to pull it or reinstall it. Its not a hard Job. Just take your time
I found it WAAAAAAY easier to just heat the pulley in the oven (never tried boiling lol) and then it just slides on the crank. A couple light taps with a rubber mallet and you have enough of the pulley on the crank that you dont have to worry about stripping the threads. Then just instal.
People also like to complain about removing the steering rack. Its take me about 15 minutes to pull it or reinstall it. Its not a hard Job. Just take your time
Instructor
Joined: Feb 2014
Posts: 136
Likes: 6
From: Lees Summit Missouri
When I installed mine I used a new GM bolt, torqued it to 37 ft-lb then measured another 240 degrees and drew a line on the balancer with white paint stick. I had a 30 to 1 torque increase tool used for truck tires, wedged it to the frame and then used a standard 1/2 in torque wrench and gingerly turned it the last 240 degrees. I have helped to other friends install their new balancer as well and the hardest part was lining up the power steering threads when putting the steering rack back in.
The proper way to install is to do the initial torque of 37 ft-lb then do an angle torque of 240 degrees to stretch the bolt. That is why you should never reuse the harmonic balancer bolt and head bolts for that matter.
You can purchase or borrow this special angle torque wrench or make some marks on the bolt head in reference to the harmonic balancer pulley for 240 degrees. Using any other method is risky, strip or snap the bolt will be a real expensive alternative.
Ray
Safety Car
Joined: Jul 2001
Posts: 4,871
Likes: 15
From: Detroit's West Side MI
The stock bolt is the way to go. The bolt was changed after the 2005 C6's had issues with the balancers coming loose and now the bolts are all the same (except C6 Z06, which is longer). It's about $8 at the dealer and does the job better than the ARP. The rubber coating under the head prevents slippage. I have used the ARP and not only was it $40, but the included washer did not fit inside the balancer.
However, as stated above, you must do the 37ftlb then 240 degree torque. Do not use the old torque to a value method. Personally, I find the easiest way is to borrow a good Snap-on impact and drive that f$%$er to 240. Takes about a minute but you're not messing with breaker bars or long ratchets. Lesser impacts can not get it all the way.
However, as stated above, you must do the 37ftlb then 240 degree torque. Do not use the old torque to a value method. Personally, I find the easiest way is to borrow a good Snap-on impact and drive that f$%$er to 240. Takes about a minute but you're not messing with breaker bars or long ratchets. Lesser impacts can not get it all the way.
Last edited by ScaryFast; Jan 16, 2015 at 04:16 PM.
Drifting
Joined: Jan 2012
Posts: 1,341
Likes: 8
From: Hopatcong New Jersey
The proper way to install is to do the initial torque of 37 ft-lb then do an angle torque of 240 degrees to stretch the bolt.........
You can purchase or borrow this special angle torque wrench or make some marks on the bolt head in reference to the harmonic balancer pulley for 240 degrees.
Guys....it's 140 degrees....NOT 240.
Melting Slicks
Joined: Sep 2005
Posts: 2,568
Likes: 212
From: Winnipeg
Ask that to me when I did my H/C/I with my fancy ARP bolt. Snapped the head off with the final torquing. GM bolt was like kindergarden. Easy Cheesy. Oh and I believe it's 140 degrees final torque till your torque wrench clicks at 240 ft lbs. !! I did it without a cheater pipe, but I do weights. :P Everything else lined up. Honestly it was so easy I couldn't believe it after reading all the horror stories here on H/C jobs. Finished up with zero leaks or issues anywhere. I was surprised since I did it by myself over the course of a long summer. Had electrical gremlins that took a while to figure out. One thing lead to another.. lol.. The rack was simple. The worst when it was all done was my lower back muscles after all the bending. Of course I was 3 years younger than now. 
Last edited by REDZED2; Jan 17, 2015 at 02:03 AM.
