Help! Harmonic Balancer Bolt Issues
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Help! Harmonic Balancer Bolt Issues
This winter I decided to freshen up my 150K LS1 by putting on a new timing chain and oil pump. I put it back together with a new harmonic balancer bolt and tightend the crap out of it with a 3 foot long cheater bar. It still came lose after 3,000 miles and the balancer slid loose all the way to the rack and pinion. Any hints on how to do it right this time would help. Thanks
Tech Contributor
Joined: Jan 2007
Posts: 19,528
Likes: 1,196
From: Dyer, IN
This winter I decided to freshen up my 150K LS1 by putting on a new timing chain and oil pump. I put it back together with a new harmonic balancer bolt and tightend the crap out of it with a 3 foot long cheater bar. It still came lose after 3,000 miles and the balancer slid loose all the way to the rack and pinion. Any hints on how to do it right this time would help. Thanks
:
Burning Brakes
Joined: Nov 2003
Posts: 1,234
Likes: 5
From: Herriman UT
A new bolt properly torqued and you shouldn't have a problem. I don't know if I could have achieved 240 ft lbs on my ARP bolt with just a 3' cheater, the torque wrench I used was about 5' long. When you've got the pulley nearly seated, make sure and use the old bolt to pull it all the way on and torque to 240 ft lbs. Then remove the old bolt and install the new bolt.
Last edited by geezel; May 7, 2009 at 11:53 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
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From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Way too much missing info here to tell you where or what EXACTLY went wrong but here is what I have seen happen WRONG in the past:
Old OEM Bolt was REUSED!
New Bolt was used but NOT TORQUED properly.
A new bolt was used but old damper was used and the interference fit between the damper snout and damper was incorrect!!
New bolt used, new damper used but bolt was NOT torqued properly.
Everything was done properly BUT,,,,the damper rotated on the crank snout causing the bolt to come loose.
Those are the scenarios that I can think of at midnight!!!
I have approx 60 HP over stock and I decided to PIN the crank to the Damper to eliminate this very issue.
BC
LUCKY,,,,,,
NO COMMENT!
Old OEM Bolt was REUSED!
New Bolt was used but NOT TORQUED properly.
A new bolt was used but old damper was used and the interference fit between the damper snout and damper was incorrect!!
New bolt used, new damper used but bolt was NOT torqued properly.
Everything was done properly BUT,,,,the damper rotated on the crank snout causing the bolt to come loose.
Those are the scenarios that I can think of at midnight!!!
I have approx 60 HP over stock and I decided to PIN the crank to the Damper to eliminate this very issue.
BC
LUCKY,,,,,,
NO COMMENT!
Tech Contributor
Joined: Jan 2007
Posts: 19,528
Likes: 1,196
From: Dyer, IN
Way too much missing info here to tell you where or what EXACTLY went wrong but here is what I have seen happen WRONG in the past:
Old OEM Bolt was REUSED!
New Bolt was used but NOT TORQUED properly.
A new bolt was used but old damper was used and the interference fit between the damper snout and damper was incorrect!!
New bolt used, new damper used but bolt was NOT torqued properly.
Everything was done properly BUT,,,,the damper rotated on the crank snout causing the bolt to come loose.
Those are the scenarios that I can think of at midnight!!!
I have approx 60 HP over stock and I decided to PIN the crank to the Damper to eliminate this very issue.
BC
LUCKY,,,,,, NO COMMENT!
Old OEM Bolt was REUSED!
New Bolt was used but NOT TORQUED properly.
A new bolt was used but old damper was used and the interference fit between the damper snout and damper was incorrect!!
New bolt used, new damper used but bolt was NOT torqued properly.
Everything was done properly BUT,,,,the damper rotated on the crank snout causing the bolt to come loose.
Those are the scenarios that I can think of at midnight!!!
I have approx 60 HP over stock and I decided to PIN the crank to the Damper to eliminate this very issue.
BC
LUCKY,,,,,,
NO COMMENT!
Race Director
Joined: Mar 2004
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From: Fort Wayne IN
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Way too much missing info here to tell you where or what EXACTLY went wrong but here is what I have seen happen WRONG in the past:
Old OEM Bolt was REUSED!
New Bolt was used but NOT TORQUED properly.
A new bolt was used but old damper was used and the interference fit between the damper snout and damper was incorrect!!
New bolt used, new damper used but bolt was NOT torqued properly.
Everything was done properly BUT,,,,the damper rotated on the crank snout causing the bolt to come loose.
Those are the scenarios that I can think of at midnight!!!
I have approx 60 HP over stock and I decided to PIN the crank to the Damper to eliminate this very issue.
BC
LUCKY,,,,,, NO COMMENT!
Old OEM Bolt was REUSED!
New Bolt was used but NOT TORQUED properly.
A new bolt was used but old damper was used and the interference fit between the damper snout and damper was incorrect!!
New bolt used, new damper used but bolt was NOT torqued properly.
Everything was done properly BUT,,,,the damper rotated on the crank snout causing the bolt to come loose.
Those are the scenarios that I can think of at midnight!!!
I have approx 60 HP over stock and I decided to PIN the crank to the Damper to eliminate this very issue.
BC
LUCKY,,,,,,
NO COMMENT!My recommendation would be to get an ARP crank bolt. First you need to seat the pulley all the way. IIRC manual states to install the crank pulley using the prescribed tool (Look on LS1 tech for a crank pulley installation tool, a VERY well spent $35), then using your OLD factory bolt, torque to 240 ft/lbs (this is hard, I have a helluva time every time I've done it). Then simply remove your old factory bolt and install the ARP Crank bolt and TQ to 190 ft/lbs. If you look at your factory bolt you should see red loctite on the threads.......I'd use it on the new bolt too.
Reason for recommending the ARP bolt is that it's reuseable.
