Valve cover gaskets 440 cork or rubber or something else?

[mbc0724]

The cork gaskets on my 71 440 are shot and seeping around some of the bolt holes. Probably have not changed them in 15 years. Should I stick with cork or try something else like rubber? What are people using these days? Thanks!

 

[Aron Gleason]

I use the thick rubber gaskets, but I also have studs to keep the gaskets in place. And I put mine on dry.

 

[Mopar Hunter]

I like to use the Moroso #93055 specially if you need to adjust your valves. They’re reusable.

If you don’t need to adj. your valves, I like to use the Fel-Pro 1610 & gasket sealer.

 

[Kern Dog]

Some people have excellent results with cork.
I haven't but then again, some think I'm weird.
Valve cover condition is critical. Your rails have to be really straight to get a good seal with any gasket. I've defaulted to the cast aluminum valve covers which seem to be better for me since I have a tendency to over-tighten things. The thin rails of the steel covers bend easy if you are not careful.
Good luck.

 

[R413]

Cork, fel-pro VS13379
Covers must be straight, everything clean, clean, clean and dry no sealer.

 

[451Mopar]

The Blue Moroso valve cover gaskets are pretty good, and can be re-used as noted.
The trick with the cork gaskets is to not overtighten them. use some blue loctite on the valve cover bolts to keep them from loosining, and use an inch-pound torque wrench to tighten them to factory spec. I'd have to look up the spec, but seems like not much more then snugging them up with a screwdriver attachment, likely less then the 72 inch/pounds used for setting transmission bands.

 

[PurpleBeeper]

I prefer cork because they conform to any imperfections on the sealing surfaces. Some harder “performance” ones do not

 

[SlinktRR]

I went back to felpro cork on recommendation from the forum and the key is inch lb torque wrench to prevent overtightening, which is really easy to do. Not a drop on aluminum heads with OEM baffled valve covers. I reuse them after solid lifter lash check.

 

[Black_Sheep]

FelPro 17941 rubber, glued to the valve cover with a light coat of grease on the side facing the head. As others have previously mentioned, I also torque them with an in/lb torque wrench to avoid warping the VC flange

 

[WileERobby]

Cork gasket + Indian Head gasket shellac = no leaks over 50 years. Requirements : straight surface + proper shellac application + proper torque tightening.

 

[AR67GTX]

I also use cork but I lightly torque them, come back and retorque, retorque, retorque, retorque…. Sometimes it takes a week and maybe 10 retorquings, depending on gasket thickness to get them stable. On the Hemi I use the steel reinforced cork FelPros. They are pretty thick and take a while to stabilize. Not sure the steel if necessary on wedge head engines. I try not to over-torque to prevent warping the flanges (after I straighten them).

I like the Permatex spray high-tack gasket sealer to adhere them to the valve covers. I’ve found out that when changing gaskets cleanup is real easy. Acetone will barely soften the sealer but PrepSol instantly liquifies it and it just wipes off. Sure beats scraping RTV off of them.

 

[mbc0724]

Lots of great suggestions--thank you everyone.

 

[gtx6970]

I also use cork but I lightly torque them, come back and retorque, retorque, retorque, retorque…. Sometimes it takes a week and maybe 10 retorquings, depending on gasket thickness to get them stable. On the Hemi I use the steel reinforced cork FelPros. They are pretty thick and take a while to stabilize. Not sure the steel if necessary on wedge head engines. I try not to over-torque to prevent warping the flanges (after I straighten them).

I like the Permatex spray high-tack gasket sealer to adhere them to the valve covers. I’ve found out that when changing gaskets cleanup is real easy. Acetone will barely soften the sealer but PrepSol instantly liquifies it and it just wipes off. Sure beats scraping RTV off of them.

Interesting timing as I was contemplating it was time to go thru the valves on mine.
And was looking at these gaskets .

Cometic Valve Cover Gasket - C5976​

I did cork 2 years ago and every once in a while, I need to tighten them down due to a leak, mostly in corners

 

[AR67GTX]

I know Cometic mostly by name and forums mention. Let us know how they work. I have a set off rubber gaskets, maybe Mr. Gasket, but have been afraid they were too stiff to conform well and seal with stamped Hemi covers.

Yes, I had a leak problem at the driver side, bottom, rear corner - the corner that has a couple relief cuts in the flange. It’s a weak area. I went through a couple gaskets on it and it just kept leaking. I flattened all the bolt holes and flange runs last year but I didn’t really have a large enough flat surface to determine if that corner was flat with the rest of the flange or not. Using straight edges didn’t show much. So this last time I took a piece of 1x2 poplar and taped the end, put couple thin shims back from the corner at the nearest bolt holes to elevate it a little and went around that corner a couple of times whacking it on the corner flange with the wood block and the hammer. Didn’t even mar the paint. Put a new gasket on and spent a few days repeatedly snugging it up. I’ve driven it 3 or 4 times since and so far that seems to have done the thick.

 

[R413]

With cork the reason the bolts get loose is the gaskets compress with time and heat cycles. The bolts are not backing out. So you need to retighten the bolts. loctite won't help anything with cork.

 

[tak419]

I've used cheap cork dry with great results. Tried Felpro rubber, which seemed hard. One sealed, one leaked. Replaced it with another Felpro rubber and it sealed. I'd say it doesn't matter, either cork or rubber.

 

[LSS&B]

I like to use the Moroso #93055 specially if you need to adjust your valves. They’re reusable.

If you don’t need to adj. your valves, I like to use the Fel-Pro 1610 & gasket sealer.

Did you use the Moroso recommended 80"lbs torque?
Or did you go with the factory torque of 40"lbs?
Thanks!

 

[lewtot184]

Felpro 1610

 

[1967coronet]

Another fel pro cork guy.
Oem style covers , I use a little bit of gasket sealer to fix them to the covers.
Tighten with a nut driver.

 

[LSS&B]

Another fel pro cork guy.
Oem style covers , I use a little bit of gasket sealer to fix them to the covers.

1969 440 rebuilt 4 years ago. Moroso 93055 Gaskets newly installed on Stock Valve Covers. Currently torqued at 40"lbs. Are you saying back off on the torque?
Generic Directions all makes and models from Moroso is 80"lbs for 1/4" thread fasteners. Seems like too much to me. FSM 40"lbs.
Have not run engine with new valve cover gaskets. Previous FelPro Cork gaskets were leaking, probably because of heat from HP manifolds.