Crank Pulley Torque Spec
Thread Starter
Instructor
Joined: Jun 2008
Posts: 220
Likes: 0
From: Somers Point New Jersey
Crank Pulley Torque Spec
Well, just last night as I was racing, my crank pulley/balancer walked off my crank and slammed my steering rack. Great, huh! 
....blood chilling scraping sounds and lots of smoke and oil.... I thought my engine was toast.
Well, I had the car towed to my shop and plan to check out the extent of the damage tonight. I know why this happened. I didn't feel comfortable putting 240ftlbs of torque on one bolt like I was recommended when installing the crank pulley last week. Ok, I'm an idiot...
What I would really love is for a few people to tell me how much they tightened their CP bolt without breaking it. Would anyone like to share so I feel a little more at ease?
....blood chilling scraping sounds and lots of smoke and oil.... I thought my engine was toast.
Well, I had the car towed to my shop and plan to check out the extent of the damage tonight. I know why this happened. I didn't feel comfortable putting 240ftlbs of torque on one bolt like I was recommended when installing the crank pulley last week. Ok, I'm an idiot...
What I would really love is for a few people to tell me how much they tightened their CP bolt without breaking it. Would anyone like to share so I feel a little more at ease?
Tech Contributor
Joined: Jan 2007
Posts: 19,450
Likes: 1,155
From: Dyer, IN
Well, just last night as I was racing, my crank pulley/balancer walked off my crank and slammed my steering rack. Great, huh!
....blood chilling scraping sounds and lots of smoke and oil.... I thought my engine was toast.
Well, I had the car towed to my shop and plan to check out the extent of the damage tonight. I know why this happened. I didn't feel comfortable putting 240ftlbs of torque on one bolt like I was recommended when installing the crank pulley last week. Ok, I'm an idiot...
What I would really love is for a few people to tell me how much they tightened their CP bolt without breaking it. Would anyone like to share so I feel a little more at ease?
....blood chilling scraping sounds and lots of smoke and oil.... I thought my engine was toast.
Well, I had the car towed to my shop and plan to check out the extent of the damage tonight. I know why this happened. I didn't feel comfortable putting 240ftlbs of torque on one bolt like I was recommended when installing the crank pulley last week. Ok, I'm an idiot...
What I would really love is for a few people to tell me how much they tightened their CP bolt without breaking it. Would anyone like to share so I feel a little more at ease?
Melting Slicks
Joined: Mar 2002
Posts: 2,203
Likes: 63
From: Staten Island NY
Because it will just come loose again.
The factory bolt is a one time use item. Been there done that. It wasnt much fun replacing the balancer, bolt and oil seal - but the folks on this forum helped me out again with instructions.
Pro
Joined: Mar 2007
Posts: 578
Likes: 0
From: Mission Viejo CA
You'll hear this a 100 times at least but, 
the GM bolt is a one time use because it is torqued to yield and it is not a torgue requirement but it specifies 140 degrees of turn for proper tightening.
If you want a replceable bolt go with the ARP bolt. If not follow the proper installation and do not re-use.
Also pin the pulley on the crank. I spun mine and am in the process of repairing it as we speak.
I am 90% thru pulling the steeering rack out right now and I am going with a powerbond 25% u/d pullley since it already has a keyway. I have the ATI crank pin drilling fixture and will pin the crank and pulley. This with the ARP bolt and a new front seal will fix my problem and is probably what you will need.
Although your damage may be more since your pulley walked. Good luck.
savage1
the GM bolt is a one time use because it is torqued to yield and it is not a torgue requirement but it specifies 140 degrees of turn for proper tightening. If you want a replceable bolt go with the ARP bolt. If not follow the proper installation and do not re-use.
Also pin the pulley on the crank. I spun mine and am in the process of repairing it as we speak.
I am 90% thru pulling the steeering rack out right now and I am going with a powerbond 25% u/d pullley since it already has a keyway. I have the ATI crank pin drilling fixture and will pin the crank and pulley. This with the ARP bolt and a new front seal will fix my problem and is probably what you will need.
Although your damage may be more since your pulley walked. Good luck.
savage1
Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
screw the stock bolt, its almost the same cost to get a nice 12 point ARP bolt...i think mine was 23$?
and that bolt is hardened and thick as hell....your not going to break it. I've torqued many of them. give it hell
and that bolt is hardened and thick as hell....your not going to break it. I've torqued many of them. give it hell
Tech Contributor
Joined: Jan 2007
Posts: 19,450
Likes: 1,155
From: Dyer, IN
I make no apologies for saying....that's just fu$king stupid
Thread Starter
Instructor
Joined: Jun 2008
Posts: 220
Likes: 0
From: Somers Point New Jersey
Ya know partner, I'm not trying to be a dick, but you got exactly what you deserved in this circumstance. You could read for hours on this subject within this forum, or you could have simply just used the service manual. Instead, you thought you knew better than all the other members of this forum who have posted their experiences, and knew better than GM.
I make no apologies for saying....that's just fu$king stupid
I make no apologies for saying....that's just fu$king stupid
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Le Mans Master
Joined: Nov 2005
Posts: 5,451
Likes: 2
From: East Peoria Illinois
Ya know partner, I'm not trying to be a dick, but you got exactly what you deserved in this circumstance. You could read for hours on this subject within this forum, or you could have simply just used the service manual. Instead, you thought you knew better than all the other members of this forum who have posted their experiences, and knew better than GM.
I make no apologies for saying....that's just fu$king stupid
I make no apologies for saying....that's just fu$king stupid
Tech Contributor
Joined: Jan 2007
Posts: 19,450
Likes: 1,155
From: Dyer, IN
If your friend ran his car with no bolt in the harmonic balancer (and at the dragstrip to boot), then you are certainly in good company.
At the end of the day, it's your car to destroy any way you see fit....
