Vance---Well, I did it again! The message inadvertantly sent to the
List was meant to go to Dennis Semanaitis, at Road &Track.
Nonetheless, I agree that the replacement head gasket does not seem to
require retorquing at some later date. At least I've never been
penalized for not doing this.
It would appear that once a new head gasket is crushed during the
tensioning of the head studs, no further dimensional changes take place.
Furthermore, studs properly torqued stay under tension, even under years
of cyclic stress. In fact these studs can be reused many times if their
yield strength have not been exceeded thru overtorquing.
Some may not agree and still re-torque their head studs. Fair enough.
But I will offer a pretty reliable simple check that requires no
removing of the valve cover and pedestals....Test the exposed head nuts
to see if you can get an extra "click" out of them! If you can, then by
all means go after the others.
Dick
From: vance.navarrette@intel.com(Navarrette, Vance) Date: Wed, Nov 30,
2005, 12:55pm To: tr6taylor@webtv.net (Sally or Dick Taylor) Cc:
6pack@autox.team.net Subject: RE: Head gaskets, II
Dick:
Actually, it is the
gasket manufacturers that have the most to say about this.
I believe that
retorquing pretty much disappeared by the end of the 60's
or so. When I look at GMHPP catalogue for example, all the gaskets I
find listed specifically
state "No retorquing necessary".
Whether or not you need
to retorque depends on what the gasket is made of.
Modern materials have pretty much eliminated the need to retorque,
except possibly
for some special applications.
Vance
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