Balancer Bolt
Thread Starter
Burning Brakes
Joined: Jul 2018
Posts: 979
Likes: 258
From: Maryland
Balancer Bolt
After reinstalling the balancer on my 69 SBC, I noticed the bolt I took off (and was going to use) had some rounding on the edges. So I've decided to get a new one and not take any chances. Interestingly, the factory assembly manual for a 69 shows a bolt (9428643) a lock washer (138494) and the washer (3739422) but apparently the guy who was working on the engine before me did not use the lock washer. So I am looking for a good replacement and came across this one:
945G Mr. Gasket Harmonic Balancer Bolt & Washer Set - JEGS
Its a grade 8 bolt and looks like the head is thicker to reduce socket slippage. Does this look like something I should order or should I just go with the stock pieces? Also, should I put a dab on blue locktite on the bolt or no?
945G Mr. Gasket Harmonic Balancer Bolt & Washer Set - JEGS
Its a grade 8 bolt and looks like the head is thicker to reduce socket slippage. Does this look like something I should order or should I just go with the stock pieces? Also, should I put a dab on blue locktite on the bolt or no?
NCM Grand Opening Veteran
Joined: Sep 2005
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From: South of giving a damn
St. Jude Donor '11, '17
Le Mans Master
Joined: Aug 2017
Posts: 8,336
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From: Cool Northern Michigan
Here is what's going to happen jpatrick.
It may not be tomorrow, or next week or in five yrs. But eventually you will be turning over the entire engine assembly with the plugs still in and BANG.
You just snapped the bolt off in the crank.
Good luck getting that out. Your worst nightmare just happened.
That bolt is in place to hold the harmonic balancer on. That's all. That's its job.
But we all know it will turn the crank with a breaker bar. So we all abuse it.
If you purchase the above, you will NEVER have to worry about breaking it.
No lock-washer needed. Just a drop of Loctite Blue.
It may not be tomorrow, or next week or in five yrs. But eventually you will be turning over the entire engine assembly with the plugs still in and BANG.
You just snapped the bolt off in the crank.
Good luck getting that out. Your worst nightmare just happened.
That bolt is in place to hold the harmonic balancer on. That's all. That's its job.
But we all know it will turn the crank with a breaker bar. So we all abuse it.
If you purchase the above, you will NEVER have to worry about breaking it.
No lock-washer needed. Just a drop of Loctite Blue.
Drifting
Joined: May 2020
Posts: 1,663
Likes: 702
From: Baton Rouge, Louisiana, metro area
ARP has their own torque (at least for the LS series). There should be instructions in the package.
I got one for my 99 when I replaced the LS1 balancer. The ARP bolt torque was a lot less than the GM factory bolt. You need to look for what ARP says. They even sent a little pack of their special lubricant with the bolt.
I got one for my 99 when I replaced the LS1 balancer. The ARP bolt torque was a lot less than the GM factory bolt. You need to look for what ARP says. They even sent a little pack of their special lubricant with the bolt.
Thread Starter
Burning Brakes
Joined: Jul 2018
Posts: 979
Likes: 258
From: Maryland
ARP has their own torque (at least for the LS series). There should be instructions in the package.
I got one for my 99 when I replaced the LS1 balancer. The ARP bolt torque was a lot less than the GM factory bolt. You need to look for what ARP says. They even sent a little pack of their special lubricant with the bolt.
I got one for my 99 when I replaced the LS1 balancer. The ARP bolt torque was a lot less than the GM factory bolt. You need to look for what ARP says. They even sent a little pack of their special lubricant with the bolt.
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Thread Starter
Burning Brakes
Joined: Jul 2018
Posts: 979
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From: Maryland
Pro
Joined: May 2017
Posts: 583
Likes: 196
From: Wisconsin
80 ft/lbs is how I read the chart with using their "fastener assembly lubricant" when installing.
Last edited by JETS C3-C4; Apr 9, 2024 at 10:30 PM.
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
JPatrick,
Remember that the Harmonic Balancer is a "press-fit" and requires a special tool to install the unit.
I wouldn't be too concerned about the bolt torque, 70 or 80 will work. The bolt just holds the balancer on.
Years from now, somebody will be trying to turn the crank over with a breaker bar and applying 100 lbs anyway.
Remember that the Harmonic Balancer is a "press-fit" and requires a special tool to install the unit.
I wouldn't be too concerned about the bolt torque, 70 or 80 will work. The bolt just holds the balancer on.
Years from now, somebody will be trying to turn the crank over with a breaker bar and applying 100 lbs anyway.
Safety Car
Joined: Oct 2004
Posts: 3,926
Likes: 739
From: Youngstown Ohio
Agree with above post. Early 283 & 327 small block chevys did not even use a balancer bolt. The dampers were simply pressed on. Only the high perf. engine crankshafts were drilled and tapped for a bolt. Your 70-80 torque is more than enough insurance.
Thread Starter
Burning Brakes
Joined: Jul 2018
Posts: 979
Likes: 258
From: Maryland
Thanks all - had the balancer rebuilt by the Damper Doc and used a special tool to put it back on. Even with the tool, i only went on so far and I had to use the old bolt and washer to get it all the way on. I agree, that balancer is not going to fall off on its own. I was thinking I would put the bolt on using the suggested 75-80 ft/lbs of torque but I know that will not be so easy. Getting the old bolt snug up at 60 ft/lbs was hard enough.
At least I know the bolt should not snap during the attempt!
At least I know the bolt should not snap during the attempt!
Instructor
Joined: Jun 2023
Posts: 201
Likes: 66
From: Orlando, FL.
The purpose of the "torque specification" is not just as a function of a load sum being incurred in an act of retention, but is rather to provide a means of targeting the "elastic" range of the fastener, and this being unique to each as differently manufactured fastener, this so as with the utilization of the fasteners' "stretch" provides a tension function that then provides resistance to the fasteners' act of rotation, this generally in the loosening direction, in service.
"Lock-Washers" are a poor choice today as they are a leftover from a different era of fastening retention systems; think about it, the only way in which a lock washer actually functions as such, is if the fastener is already loose!
For the damper bolt, use Loctite!
Scott.
"Lock-Washers" are a poor choice today as they are a leftover from a different era of fastening retention systems; think about it, the only way in which a lock washer actually functions as such, is if the fastener is already loose!
For the damper bolt, use Loctite!
Scott.