Crank pulley/balancer bolt torque specs?
Thread Starter
Drifting
Joined: Jan 2004
Posts: 1,736
Likes: 2
From: Broken Arrow Oklahoma
St. Jude Donor '09
Crank pulley/balancer bolt torque specs?
Ok my balancer slipped and moved out after a cam swap. I have the rack moved out of the way and I am ready to wrench. I need to know what the torque spec is. I have seen 200 and 250 ft lbs listed. After you torque the bolt to 250 why remove it and use a new bolt?
I followed ls1howto and torqued to 200 then installed a new bolt and torqued it to 37lbs and then marked it and turned it another 140deg. My only mistake was no locktite because the new bolt looked like it had some on it from GM.
Does the balancer spin on the crank and back the bolt out? I know someone will mention crank pinning or ARP bolt. I also know tons of people do not have this problem after cam swaps using the stock bolt only. Does anyone have a better way to go at this? Or should I just repeat my steps and loctite it?
Thanks Steve
I followed ls1howto and torqued to 200 then installed a new bolt and torqued it to 37lbs and then marked it and turned it another 140deg. My only mistake was no locktite because the new bolt looked like it had some on it from GM.
Does the balancer spin on the crank and back the bolt out? I know someone will mention crank pinning or ARP bolt. I also know tons of people do not have this problem after cam swaps using the stock bolt only. Does anyone have a better way to go at this? Or should I just repeat my steps and loctite it?
Thanks Steve
Melting Slicks
Joined: Aug 1999
Posts: 3,452
Likes: 3
From: Spring, TX
You torque the balancer back on to 250ft lbs. Then use a new bolt to 37lbs then twist 140 degrees.
Yes the balancer can spin on the crank and cause the bolt to back out.
Did you re-use your balancer? I think this is the main problem. Re-using a balancer that has already been stretched onto the crank once will not hold the same again when stretched over the snout. I would always use a new balancer whether it was stock or not. Otherwise I would pin crank. Actually if I did this again I would key the crank anyways.
I feel your pain. My stock balancer failed in the rubber section and slid into the front engine cover. It did a lot of damage. While I was in there fixing it I did a cam swap. Getting everything out of the way then fighting with the bolt was a real experience.
Yes the balancer can spin on the crank and cause the bolt to back out.
Did you re-use your balancer? I think this is the main problem. Re-using a balancer that has already been stretched onto the crank once will not hold the same again when stretched over the snout. I would always use a new balancer whether it was stock or not. Otherwise I would pin crank. Actually if I did this again I would key the crank anyways.
I feel your pain. My stock balancer failed in the rubber section and slid into the front engine cover. It did a lot of damage. While I was in there fixing it I did a cam swap. Getting everything out of the way then fighting with the bolt was a real experience.
Safety Car
Joined: Apr 2004
Posts: 3,818
Likes: 4
From: San Bruno ca
The crank bolt is suppose to strech when you torque it down. That is why you use the old bolt first. Trust me it is worth the time and money to use a old bolt. The previous owner of my car did that and it end up cost me a new motor 
Racer
Joined: Apr 2005
Posts: 466
Likes: 0
From: Greenville NC
My UD pulley bolt backed out twice this week- yesterday it was on the dyno when it happened. Turns out you can only use those stretch bolts once 
like everyone else said, tq the crap out of the original bolt to get that pulley on good and tight, then pull teh bolt, put the new stretch bolt on (with loctite!!) and tq to 37ft/lbs- then another 140degrees, and hopefully it'll stay on.
Good luck getting that steering rack out of the way- its a real PITA!
like everyone else said, tq the crap out of the original bolt to get that pulley on good and tight, then pull teh bolt, put the new stretch bolt on (with loctite!!) and tq to 37ft/lbs- then another 140degrees, and hopefully it'll stay on.
Good luck getting that steering rack out of the way- its a real PITA!
Drifting
Joined: Dec 2003
Posts: 1,268
Likes: 0
From: Ca
Originally Posted by STLBLUES
Ok my balancer slipped and moved out after a cam swap. I have the rack moved out of the way and I am ready to wrench. I need to know what the torque spec is. I have seen 200 and 250 ft lbs listed. After you torque the bolt to 250 why remove it and use a new bolt?
I followed ls1howto and torqued to 200 then installed a new bolt and torqued it to 37lbs and then marked it and turned it another 140deg. My only mistake was no locktite because the new bolt looked like it had some on it from GM.
Does the balancer spin on the crank and back the bolt out? I know someone will mention crank pinning or ARP bolt. I also know tons of people do not have this problem after cam swaps using the stock bolt only. Does anyone have a better way to go at this? Or should I just repeat my steps and loctite it?
Thanks Steve
I followed ls1howto and torqued to 200 then installed a new bolt and torqued it to 37lbs and then marked it and turned it another 140deg. My only mistake was no locktite because the new bolt looked like it had some on it from GM.
Does the balancer spin on the crank and back the bolt out? I know someone will mention crank pinning or ARP bolt. I also know tons of people do not have this problem after cam swaps using the stock bolt only. Does anyone have a better way to go at this? Or should I just repeat my steps and loctite it?
Thanks Steve
Been through this twice thanks to ####...pin that sucker, use new bolt and balancer to recomended specs w/red lock tight.
Thread Starter
Drifting
Joined: Jan 2004
Posts: 1,736
Likes: 2
From: Broken Arrow Oklahoma
St. Jude Donor '09
Ok a new balancer will be purchased this week. I do not want a underdrive because I have enough hp as it is. I have the rack moved and a new bolt in hand. I think the new balancer and locktite will get me back on the road.
Anyone make a stock size balancer thats better than gms?
Thanks, Steve
Anyone make a stock size balancer thats better than gms?
Thanks, Steve
Team Owner
Joined: Mar 1999
Posts: 22,025
Likes: 192
From: At the beach in little Rhody
Originally Posted by gonbad
Did you re-use your balancer? I think this is the main problem. Re-using a balancer that has already been stretched onto the crank once will not hold the same again when stretched over the snout. I would always use a new balancer whether it was stock or not. Otherwise I would pin crank.
I installed the ATI, and the interference called for is 0.0007 - 0.0009". I don't know what the stock balancer interference fit is, but I personally believe that they should not be re-used either.
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Race Director
Joined: Apr 2004
Posts: 16,135
Likes: 5
From: Newberry FL
Cruise-In VIII Veteran
St. Jude Donor '07
Originally Posted by gonbad
You torque the balancer back on to 250ft lbs. Then use a new bolt to 37lbs then twist 140 degrees.
Yes the balancer can spin on the crank and cause the bolt to back out.
Did you re-use your balancer? I think this is the main problem. Re-using a balancer that has already been stretched onto the crank once will not hold the same again when stretched over the snout. I would always use a new balancer whether it was stock or not. Otherwise I would pin crank. Actually if I did this again I would key the crank anyways.
I feel your pain. My stock balancer failed in the rubber section and slid into the front engine cover. It did a lot of damage. While I was in there fixing it I did a cam swap. Getting everything out of the way then fighting with the bolt was a real experience.
Yes the balancer can spin on the crank and cause the bolt to back out.
Did you re-use your balancer? I think this is the main problem. Re-using a balancer that has already been stretched onto the crank once will not hold the same again when stretched over the snout. I would always use a new balancer whether it was stock or not. Otherwise I would pin crank. Actually if I did this again I would key the crank anyways.
I feel your pain. My stock balancer failed in the rubber section and slid into the front engine cover. It did a lot of damage. While I was in there fixing it I did a cam swap. Getting everything out of the way then fighting with the bolt was a real experience.
Well said!
Melting Slicks
Joined: Aug 1999
Posts: 3,452
Likes: 3
From: Spring, TX
Originally Posted by STLBLUES
Ok a new balancer will be purchased this week. I do not want a underdrive because I have enough hp as it is. I have the rack moved and a new bolt in hand. I think the new balancer and locktite will get me back on the road.
Anyone make a stock size balancer thats better than gms?
Thanks, Steve
Anyone make a stock size balancer thats better than gms?
Thanks, Steve
Racer
Joined: Jun 2005
Posts: 466
Likes: 0
From: Va. Beach VA
Seriously guys, you replace the balancer just because you remove it? Must be something exclusive to a Gen III or newer. I've been working on SB Chevys for 30 years and never heard of having to do that. If you remove it with a puller, what damage have you done?
Thread Starter
Drifting
Joined: Jan 2004
Posts: 1,736
Likes: 2
From: Broken Arrow Oklahoma
St. Jude Donor '09
Originally Posted by kdub1
Seriously guys, you replace the balancer just because you remove it? Must be something exclusive to a Gen III or newer. I've been working on SB Chevys for 30 years and never heard of having to do that. If you remove it with a puller, what damage have you done?
Drifting
Joined: Dec 2003
Posts: 1,268
Likes: 0
From: Ca
Originally Posted by STLBLUES
The balancer is press fit with no key way. The only thing that holds it on is the bolt and a tight tolerance. I wish gm would have made it just like the old small blocks.
