Valve cover gasket issue.

66Hardtop

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Last week I put new valve cover gaskets in the 383 in my 66 Polara. The old gaskets were originals and petrified. I went with the fel-pro high temperature rubber ones instead of cork. After putting them in all was well but after a few days I noticed the drivers side leaking again. I tightened the bolts and the leak was gone for a few days. Basically I have to retighten it every couple days. These gaskets when I got them were pretty stiff and not very pliable, more like a stiff hard rubber. Maybe it just needs a few heat cycles to conform? Has anybody else used these ones or should I stick to the cork ones? Thanks.
 

HWYCRZR

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Interesting I just put one of these on when I pulled my head the other day. The cork one was new but torqued down once. On a brand new engine I didn’t want to any leak chances so I put a new felpro hi temp on the side I removed. I left the other cork. See what works best longer term. The instructions were clear that adhesive should be used to secure it to the valve cover so it cannot move prior to installation. I guess I will see if one works better than the other.
 

Newport 66

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Make sure the area around the bolt holes on the valve covers is flat. Overtightening can " concave" that part of the cover and they won't seal. I use gascasinch on both sides of the new gasket. If using aluminum valve covers use a thin bead of silicone sealer.
 

Newport 66

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I just put the RealGasket Silicone VCGs on mine, and FOLLOW THEIR DIRECTIONS! They are doing great! Initial install, torque to 20-25 INCH pounds, not FOOT pounds. Bring it up to operating temperature, and retorque them.

Valve Cover Gaskets - MOPAR Big Block V8 - Silicone Gaskets - Real Gaskets Tennessee


No adhesive, no RTV. I put a drop of blue Loctite on the bolts though.
I wondered how well those performed. I seem to recall MoPar having orange silicone formed gaskets for B/RB engines. Thanks for the info!
 

BLUPORT

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I wondered how well those performed. I seem to recall MoPar having orange silicone formed gaskets for B/RB engines. Thanks for the info!
I was very impressed. They resist the high heat of the exhaust manifolds, and form fit to fill any imperfections in the heads or VCs.
 

1978 NYB

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I have used these FelPro VS 50145 R Hi-Performance valve cover gaskets for a 1969 R/T 440 for decades and never had one leak. They are black fiber constructed. They don't move at all during installation. I use a light coat of adhesive just out of habit.

20190402_195903.jpg
 

Dobalovr

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I have used these FelPro VS 50145 R Hi-Performance valve cover gaskets for a 1969 R/T 440 for decades and never had one leak. They are black fiber constructed. They don't move at all during installation. I use a light coat of adhesive just out of habit.

View attachment 274825

Same thing I use every time Bob! I put the gasket on the cover first with some copper permatex lay them gasket side down on the bench overnight install next day good to go no leaks!
 

1978 NYB

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Same thing I use every time Bob! I put the gasket on the cover first with some copper permatex lay them gasket side down on the bench overnight install next day good to go no leaks!

:thumbsup::thumbsup:

:usflag::canada:
 

66Hardtop

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I popped the drivers side cover off and the gasket disintegrated. I picked up a cork one and so far so good.
 

BLUPORT

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When I took mine off, they had turquoise overspray on them, but my valve covers had never been painted, aside from the factory. They were cork. Original? Maybe?
 

Castle

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I was told to go with cork.... the silicone ones can’t handle the high engine heat and slide all over... especially if they are over tightened.
 

BLUPORT

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I was told to go with cork.... the silicone ones can’t handle the high engine heat and slide all over... especially if they are over tightened.
Silicone is more heat resistant than cork, and if you follow the directions, they're really as good as it gets.
 

BLUPORT

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I hear you, just going with what I was told.... I have the combo cork/silicone on mine.... no problems
I have no stock in Silicone, just that it's the first time I've used it, and I'm more than happy with it.

Not counting my wife's lady lumps, but I digress.
 
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