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Leaky valve cover gasket

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Spit_Newbie

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Hello all, I'm running an after market valve cover. The finish is pollished. My gasket slipped out of position and started leaking like a siv. I corrected the gasket location and cranked down on the nuts to try to compress the cork a little more and the gasket split on me. Any suggestions to correct this small problem? Thanks, Spit Newbie.
 
Well, obviously you'll need a new gasket /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

Check the cover to see if you've distorted it by over-tightening. If it's steel, you can probably work it back into shape, but alloy may have to be replaced.

I've had pretty good luck with gluing the gasket to the cover with RTV or Permatex. Take whatever steps are necessary to hold the gasket in place, then set it lightly on a flat surface while the glue dries. Then use Hylomar on the side of the gasket next to the head. With luck, that will let you remove and reinstall the gasket many times (leaving it glued to the cover, but applying a fresh coat of Hylomar each time).
 
ditto.

I use gasket adhesive (pertmatex spray) or good ol' fashioned "gorilla snot" (3m weatherstrip adhesive) to tack the gasket to the valve cover to keep it from slipping.

I don't use anything on the bottom surface usually, but sometimes I'll use heavy grease to aid sealing.
 
If you over tighten the valve cover, it actually lifts up the front and or rear of the cover and will certainly leak. In your case, when you went too tight it split.
When I replaced mine, I cleaned the rim of the valve cover really good, glued the gasket on with gasket cement, snugged it on the cleaned head, ran the engine for a while until there was a small seepage from the back. Then I snugged it a little more and it has been perfect. "Snug" is the key word here. I think that is why they went from hex nut to Flathead nuts on the stock valve covers on later models. By using a screwdriver, it's harder to over tighten the valve cover.
 
I recently re-did my gasket, using a technique picked up from earlier posts in this forum.

I used Indian Head shellac (aviation sealer) on one side of the gasket to stick the gasket to the rocker cover and hold it in place. I cleaned off the cylinder head carefully and applied a light coating of grease to the bottom side of the gasket, mounted it on the head and torqued it down to spec (2 lb/ft as I recall).

No leaks.

As suggested by others, do make sure the bottom edges of the rocker cover are still nice and flat, or that the sides have not been splayed out by too much tightening on the nuts.
 
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