Leaky valve covers
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Fel-Pro 'combination' gaskets, which are a mixture of sythetic rubber and cork, IMO. Both sealing surfaces need to be flat...both need to be clean (as in NO oil/grease and wiped clean with lacquer thinner or gasoline, etc.). Sit the gasket in place, sit the valve cover on top, use load spreaders (if they were required for your engine), insert bolts, then torque ALL bolts to 30% of load...then to 70% of load...then to final torque. After that, they will not leak...unless there is another physical route for the oil to pass through.
Race Director
Joined: Nov 2002
Posts: 12,142
Likes: 54
From: Taylor Michigan
Almost any brand will work, its the preparation that's critical....You need clean and flat surfaces to start with and a real good hard setting adhesive spread over the valve cover lip. Then and lay the gasket into the cover and allow to completely set the full distance around the cover. If you have to use a weight to accomplish this do so...3M yellow weather stripping cement #8011 I believe, is my glue of choice as its almost bullet proof to get off....Held firmly in the cover prevents accidental bumping against the rockers and not getting the gasket sealed completely all over....And a note, Silicone is not a glue, its a gasket that's almost always incorrectly used for an adhesive.....
Just grease the head surface and apply the valve cover with the gasket firmly stuck in the cover......you may have to re-tighten the screws a few times but that's normal with cork style gaskets
Just grease the head surface and apply the valve cover with the gasket firmly stuck in the cover......you may have to re-tighten the screws a few times but that's normal with cork style gaskets
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Correctamundo 
Team Owner
Joined: Aug 1999
Posts: 30,995
Likes: 99
From: Ontario
Melting Slicks
Joined: Mar 2005
Posts: 2,838
Likes: 10
From: Austin TX
With stamped steel valve covers I'd use a quality cork or composite gasket with RTV around the entire perimeter on the valve cover, then use some RTV on heads on the lower rails and back corners where oil pools. When valve covers leak, that's where it will happen 9 times in 10.
I've not had any luck whatsoever with stamped steel valve covers and the expensive neoprene (blue) gaskets with the integral washers that prevent over-tightening. They're great with aluminum valve covers which are far more rigid. RTV isn't used with these gaskets.
With stamped steel you need to rely on RTV to help with the inherent uneveness of stamped steel.
The gray RTV is good. It's much easier to remove and clean up when it's time to R&R parts.
As a side, leaking valve covers at the rear of the engine have led to more misdiagnosed leaks than anything. People pull their tranny's to replace crank seals, or pan gaskets, etc.
Put RTV to work for you.
Good luck!
I've not had any luck whatsoever with stamped steel valve covers and the expensive neoprene (blue) gaskets with the integral washers that prevent over-tightening. They're great with aluminum valve covers which are far more rigid. RTV isn't used with these gaskets.
With stamped steel you need to rely on RTV to help with the inherent uneveness of stamped steel.
The gray RTV is good. It's much easier to remove and clean up when it's time to R&R parts.
As a side, leaking valve covers at the rear of the engine have led to more misdiagnosed leaks than anything. People pull their tranny's to replace crank seals, or pan gaskets, etc.
Put RTV to work for you.
Good luck!
Last edited by 73, Dark Blue 454; Sep 15, 2010 at 10:06 PM.