>My understanding is that they do not need to be replaced. The bolts in my
>car are 35 years old and have been off and on quite a few times.
>There are bolts that are meant to stretch and these must be replaced each
>time. The head bolts are not of that type.
>john
Yes, some bolts are under cut, and are meant to stretch, but the stretch is
measured, and stretch used instead of torque for tightening. They also are
multi-use, and arent tossed at each use, but rather a log is kept for each
fastener, and when the fastener does NOT return to its static length, then
the fastener is tossed.
It could'nt hurt to replace your head bolts if you dont know how many times
that they have been cycled. Call it cheap insurance that you'll only do
it once.
Jarrid Gross
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