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MG MGA - head gasket

I'm replacing the head studs on a rebuilt engine that has had the head torqued down but never run. I have a Payen head gasket installed now, can I reuse it or should it be replaced?

Thanks, George
G Goeppner

Are you feeling lucky? Are you willing to serve the consequences if the head gasket fails? It sounds like something I would do with my own car, but I wouldn't recommend it to anyone else.

Just out of curiosity, why are you replacing the head studs? The factory issue studs with "22" stamped on the top end are some of the best, pretty much good forever if not abused or damaged. Some recent replacement studs are garbage, and it is pretty much impossible to tell without destructive testing.
Barney Gaylord

Barney - the worst studs out there are the ones with a sharp cutoff at the top of the bottom (UNC) thread - these fail just at the top of that thread.

either 22 or a dimple - both will go happily to 55 ft lbs. I agree, as long as the stud is not damaged or rusted then I will reuse with no worries at all.
Chris at Octarine Services

Barney, when I installed the head, I didn't know that the studs with 22 on the end could be reused, I have those studs. I assumed a new set was needed, but I got that "bad" feeling on a couple of them when torqued, like maybe they stretched a lot. So I wanted to replace them, to avoid a broken stud when re-torqueing later. So its ok to reuse the studs with 22 stamped on the end?

Thanks as always,
George
G Goeppner

For the original studs, lay it on a table and roll it to see if it's straight. Then if you can spin new nuts down the threads with your fingers it should be good to go.

The only way I know for sure to test replacement studs is destructive testing. Put one of the new studs in a fixture and pull it up to at least 65 lb-ft torque to see what happens.
Barney Gaylord

A sheet of glass is a good surface to test on.
Keith Lowman

This thread was discussed between 10/08/2013 and 13/08/2013

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