using extentions on torque wrench cause headgasket leak

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If you used the proper size 1/2" drive torque wrench I'd say no, but if you used some wimpy 3/8" drive with an extension, I'd say yes you were probably flexing the extension. Did you do the proper torque sequence when tightening them? That is usually the cause of a head gasket installation gone wrong. my .02
 
Rule of thumb is increase torque 1/2 lb for every 1" of extension used. The torque spec for the headlbolts is 65-72 on the final sequence, so even with a short extension and no increase you will still hit the 65, so I would say unless you had like a 12" extension, thats not the problem.
 
Tonys89GT said:
Rule of thumb is increase torque 1/2 lb for every 1" of extension used. The torque spec for the headlbolts is 65-72 on the final sequence, so even with a short extension and no increase you will still hit the 65, so I would say unless you had like a 12" extension, thats not the problem.


That's some good advice:nice:
 
The rule of compensating torque when using an extension on a torque wrench refers to when you change the drive end length of the wrench, i.e. using a breaker bar on the wrench for added torque. When that's the case, you use the formula

S=

T x La
-------
La x Ea

S being your answer, T is torque applied at end of adapter, La is length of handle, and Ea is length of extension in inches.

I've never heard of adjusting final torque when using just a socket extension.. then again we go strictly by the book only where I work. :shrug:
 
I've never heard of increasing torque values based on using extensions... but I'm not a machinist either. When I installed my heads, the torque specs were in three steps. They went 35, 50, 70lb/ft and then for the long bolts, increase torque by 10lb/ft.