Impact to remove head bolts?
Thread Starter
Race Director
Joined: Dec 2002
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From: Baltimore suburbs Maryland
Impact to remove head bolts?
About to pull my heads, started with the passenger side. The 15 mm bolts wow, those were stuck 
I so far did it with a breaker bar with cheater, but some of them require a really odd position almost me climbing onto the windshield. Wondering if it's acceptable to impact off these bolts. I'd start at the lowest setting and progressively move higher. Saw a thread on LS1Tech about this but the opinions were mixed. Don't want to run into potential damage like the cradle nuts but dang using an impact would save lots of time and swearing. I'll be installing the ARP studs and yes, those will be installed completely by hand, with a torque wrench, in the correct sequence 
I so far did it with a breaker bar with cheater, but some of them require a really odd position almost me climbing onto the windshield. Wondering if it's acceptable to impact off these bolts. I'd start at the lowest setting and progressively move higher. Saw a thread on LS1Tech about this but the opinions were mixed. Don't want to run into potential damage like the cradle nuts but dang using an impact would save lots of time and swearing. I'll be installing the ARP studs and yes, those will be installed completely by hand, with a torque wrench, in the correct sequence
Last edited by ericdwong; Jan 8, 2016 at 12:30 PM.
Burning Brakes
Joined: Aug 2010
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From: Raleigh NC
The cradle nuts cant have an impact used on them because you will break the Rivets that hold them in place. The head bolts have no rivets. But what they do have is a tendency to break every once in a blue moon. So I wouldn't use the impact to break them loose. Break them loose by hand and then take them out with the impact if you want. But Head bolts would be one place I wouldn't use air unless I had to.
Drifting
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I used a breaker bar to remove my head bolts and was pouring sweat after removing them. Looking back there is no retainers or anything like is the case the with the front cradle bolts that could be damaged. I think you are good to go with air tools if you break them loose using breaker bar.
Found this thread...
http://ls1tech.com/forums/generation...air-tools.html
Found this thread...
http://ls1tech.com/forums/generation...air-tools.html
Last edited by tommypenguin; Jan 8, 2016 at 12:38 PM.
Melting Slicks
Joined: Mar 2012
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When I rebuilt my LS1 I used a breaker bar and did it by hand. I came to the decision from talking with the techs at the local Chevrolet dealer. They said due to the aluminum block and the possibility of thread damage with the impact they broke them lose by hand and then used a impact turned down to low power to remove them. 
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breaker bar to break them loose and a cordless impact the rest of the way works pretty good... I would never use an impact to initially break them loose
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