VC Gasket (archive)

Here's what I learned from my experience
with a pesky leaky VC gasket on the M60
V-8.
First, they seem to leak from the back right
by the fire wall, and just where a leak will drip
onto the exhaust and make it stinky.

Second, I've seen several occasions of roughness
in the valve cover casting (and also rough spots
where the paint is coming off). I believe that
this might exacerbate any leaks that tend to
develop.

Third, when you change the gaskets, it's
important to clean all mating surfaces really
well. I put on a pair of leather gloves (so I
don't slice a knuckle on a rough casting edge),
and clean up with an old linen rag and some
liquid wrench (sprayed on the rag). If there're
still deposits present, I'll carefully scrape with
a putty knife or gasket scraper (do NOT gouge the
head casting!). I also cleaned by covers (incl the
groove for the gasket. There were a few rough
spots that looked like either casting problems or
paint roughness. I smoothed them with 600 grit
sand paper (not perfectly smooth, but at least
not rough anymore), followed by a quick pass with
super fine Scotch brite.

Fourth, OBEY the torque specs, otherwise, you risk
warping your VC to the point where the pressure
around the perimeter of the gasket is really
uneven. Sure fire way to cause another leak.

Use new bolt seals.

After having done this, my M60 is leak free.

John

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