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ChrisBennet ChrisBennet is offline
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Join Date: Aug 2001
Location: Nashua, NH USA
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Re: Re: Broken head stud on 1984 Carrera

Quote:
Originally posted by kach22i
Interesting, this answers one of my long standing unanswered question that of: When doing valves will a shop/can a shop check for broken head studs.

I was wondering if a shop with good intentions but bad luck would check head studs by torqueing them to I believe 26 lbs and accidently snap a few. I suppose not all shops would tell you they messed up, and would dab a little lock-tight on them and give it back to you. Would not take long for the problem to show up, right?

So far, so good with mine, but I can't help feeling the Dilivar's are a time bomb waiting to go off.
I don't think any shop familiar with 911's is going to retorque head studs on a motor that hasn't been recently rebuilt. They know that "retorquing" an old rusty head stud is a recipe for breaking studs and they will let sleeping dogs lie. If anything, they'll give them a little twist to check that they aren't broken already. Usually the stud with a attached nut is just lying there when you remove the valve cover. (The last one I saw had an extra head stud washer lying with it. What the ???)

I think torquing a dry rusty fastener will yield a quite different bolt stretch value than what you'd get torquing them under rebuilt conditions.

Does anyone even use the simple torque method anymore? I use the later torque+angle any method as specified in the '84-'89 Carrera manual.

Perhaps Henry will weigh in and correct me?

-Chris
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Old 08-15-2004, 02:24 PM
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