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[VAC] Re: Smoke & Tears



The biggest problem with steel valve covers is bending the flange by over
tightening, or tightening too fast.  GM used to have (maybe still does) an
oval washer for the fastening bolt to spread the load over a larger area  of
the flange to minimize bending.

Neoprene rubber gaskets require a lot less tightening torque to seal than
cork.

The cheapest good solution would be to straighten the steel valve cover's
flange and then install neoprene gaskets.

Follow the criss cross tightening sequence in the engine shop manual.  But
MOST IMPORTANT tighten each bolt to a low torque, following the tightening
sequence pattern.  Then increase the torque a little and repeat the
sequence.  Up the torque again  and tighten as above.  Repeat this sequence
with modest torque increases until the specified torque is reached.

A cheater technique is to use some Silicone RTV gasket material on both
sides of the gasket.  Permatex makes it and it really works.  Some vehicles
don't even have gaskets, just use the RTV (room temperature vulcanizing
[cure])  Just be sure all surfaces are clean and free of oil and grease, and
let the material dry for the required time before putting the vehicle in
service.

Oliver Filippi