You should NOT torque the studs into the block. When you torque the nuts
onto the top of the studs, you are stretching the stud and providing
clamping force. When you tighten a stud into the block, the progress stops
when you reach the end of the threads cut either on the stud or in the
bottom of the hole in the block. Further tighening forces unthreaded areas
where they shouldn't be and two metalic objects, the block and the stud,
try to occupy the same space. I have heard some interesting new wave
scientific theories that may allow this but for more general applications,
we should consider this impossible. Something has to give and this is
often the block. The hole spreads and cracks appear in the relatively
brittle cast iron. Again, I have yet to run into a practical application
where this could be considered a "good thing."
Personally, I prefer to chase the threads clean with the appropriate tap /
die and set the studs by hand. Call me Mr. Cautious but I back them out
1/2 turn or so to completely avoid any possible issues. I am not sure if
MG's have blind or open holes into the block but if the cylinder stud holes
are open to antifreeze, use a sealer specifically for this application.
Your local automotive store or your Chevy dealer should have this
available.
Regards,
Bill Eastman
61 MGA living in fear of the next thing I will take apart to "fix"
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