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Crank bolt torque?

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Old Sep 30, 2017 | 02:52 PM
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Default Crank bolt torque?

As stupid as this sounds, I don't recall doing the crank bolt torque procedure when i put my motor back together, I know, how the hell could I not remember doing that!! Fortunately, I haven't put many miles on it.. I have a new crank bolt that I can use. My thought was, crank the existing bolt to 240, back it off and replace with the new and follow the rest of the process.. Does this sound reasonable? Or should I pull the pulley and start over? Also, is there a DIY way of holding the crank from spinning? If not, I'll order the tool/holder or track one down and do this next week.. TIA
13' silverado 6.2 auto..
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Old Oct 1, 2017 | 05:30 PM
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Originally Posted by JJK
As stupid as this sounds, I don't recall doing the crank bolt torque procedure when i put my motor back together, I know, how the hell could I not remember doing that!! Fortunately, I haven't put many miles on it.. I have a new crank bolt that I can use. My thought was, crank the existing bolt to 240, back it off and replace with the new and follow the rest of the process.. Does this sound reasonable? Or should I pull the pulley and start over? Also, is there a DIY way of holding the crank from spinning? If not, I'll order the tool/holder or track one down and do this next week.. TIA
13' silverado 6.2 auto..
Very reasonable. Keep in mind that the 240 is with the balancer NOT seated fully.

If the balancer is already seated fully, I believe it's 37ft lb.
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Old Oct 1, 2017 | 10:07 PM
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I know of GM technicians that stick a little red lock tite on it and hit it a few times with an impact.
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Old Oct 2, 2017 | 01:34 PM
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Originally Posted by madmann26
Very reasonable. Keep in mind that the 240 is with the balancer NOT seated fully.

If the balancer is already seated fully, I believe it's 37ft lb.
Good point. Spec on new bolt is 37 ft lb, then 140 degrees.. From what I've read it's tough to get the 140 out of it. Also, keeping the crank from turning is a challenge.
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Old Oct 3, 2017 | 04:06 PM
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I put a 24 inch breaker bar on it, then a 2 foot piece of pipe, then pulled till the breaker bar made a smiley face. Done!!!!!
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Old Oct 3, 2017 | 08:50 PM
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i use a ratcheting 1/2 inch breaker bar i got online. it make putting the bolt on pretty easy.
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Old Oct 5, 2017 | 10:06 PM
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Originally Posted by JJK
Good point. Spec on new bolt is 37 ft lb, then 140 degrees.. From what I've read it's tough to get the 140 out of it. Also, keeping the crank from turning is a challenge.
Yeah that 140* is tough. Used a 25" pullbar with a jack handle as a cheater got me close but the engine stand started to roll on it's casters. Pushed the engine/stand against the workbench, pulled up a chair, two feet on the engine stand frame, pulled hard... SNAP!

My heart skipped a couple beats thinking I'd snapped off the crank bolt! When I saw the broken impact socket (or what I thought was and impact socket) I could finally breath again!

Crank bolt torque?-yhsggrv.jpg

See my mark... I'm calling it 140* anyway lol

Crank bolt torque?-1ce2omd.jpg
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Old Oct 7, 2017 | 11:16 PM
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Originally Posted by 2002_Z28_Six_Speed
i use a ratcheting 1/2 inch breaker bar i got online. it make putting the bolt on pretty easy.
Wouldn't that just be a ratchet?
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Old Oct 9, 2017 | 08:51 AM
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Originally Posted by 2xLS1
Wouldn't that just be a ratchet?
Not when the handle is several feet long. It is what they are called in the catalogs.
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Old Oct 10, 2017 | 02:57 PM
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Ya I broke a large half inch drive snap on ratchet trying to get to 140 degrees. My buddy who is a mehanic just puts some loctite on them and runs it in with an impact.

Fwiw when I did the wife's car I stretched it a little past 90 and stopped.
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