Valve cover gasket opinion...Cork vs Rubber

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Michael Brisebois

Michael Brisebois

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I always seem to have seen to have difficulty getting my valve covers to seal well on my 273. What do you guys like...and do you use gasket sealer?
 
both will work, I've used both. I prefer cork with a thin coat of Indian Head shellac. I take them off and on many times without buying new. Trick is don't overtighten.
 
I'll use either but prefer rubber. RTV on the cover side. Lightly peening the flange hole areas flat first is one of the big keys to a good seal, as well and juuust snugging them down, not torquing them to any large degree. Looks like I just said the same thing as WR above!
 
Post a couple of pictures of the valve covers & we might be able to see why you have a sealing problem.
 
I use the cork with the impregnated rubber on mine. Yes, like mentioned, make sure the gasket rail is flat especially around the bolt holes and don't over torque.
 
I've always had decent results with cork.

All mentioned above, move around the covers with a small hammer and make sure all holes are flat, clean cover well and apply some RTV (doesn't require gobs) install gasket on cover and let set up overnight allowing for the gasket to "stick" to the cover.

Make sure surface on the head is clean and there isn't old gasket material stuck.

As a final step I use my finger and smear a little grease all the way around the gasket where it mates to the head, reason being if you need to remove the covers the grease helps keep the gasket from sticking to the head.

DO NOT over tighten.

I have removed covers and reused the gasket in place several times without a leak. YMMV
 
I use rubber glued to the valve cover with yellow 3M weatherstrip adhesive, little studs in the cylinder heads, and nuts with captive lock washers.

Tighten gently with a little screwdriver type handle and a 7/16" socket. Valve cover can be removed and replaced whenever (for valve adjustment, etc.)

Another good idea is washers that spread the load (last two fotos). You will need all the help you can find.

handle.jpg


stud.jpg


spreader1.jpg


spreader2.jpg
 
I use oil on the head side, and with sheetmetal covers adhesive on the cover side. I had some old McCord gaskets that were cork/rubber made from 4 pieces glued together - they sucked and fell apart. with cast aluminum covers I run "black rubber" cheap fel pro gaskets - retorque - no leaks.
 
I've had the same set of rubber & steel sandwich gaskets on the race car for 9 years with no problems. Keep in mind, I have a solid lifter roller cam in the car & routinely pull the covers to check the lash.
 
Save yourself a lot of grief and get Moroso blue gaskets . guaranteed not to leak . Torque them to 8-12 ft.lbs. Most v.c.gasket leaks come from overtightening .
 
Quoting the post made before this one #18 above: "Torque them to 8-12 ft.lbs. Most v.c.gasket leaks come from overtightening."

Please be careful, 1972 Chrysler Factory Service Manual (page 9-93) lists small block torque specs for "cylinder head covers" (valve covers) as 40 INCH/LBS which works out to only 3.33 ft/lbs (40 divided by 12 = 3.33). That's why I only use a screwdriver handle adapted to use a small socket.

torque specs from FSM.png
 
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I have them on my 383 and they don't leak with cast valve covers . rubber leaks and cork drys up and sticks to everything
 
[QUOTE="Michael Brisebois]I always seem to have seen to have difficulty getting my valve covers to seal well on my 273. What do you guys like...and do you use gasket sealer?[/QUOTE]

As weird as this sounds, the 3'rd 'short fuse' 273 (built
circa '79) leaked from the right rear and left center !!!
--- Light Bulb ---
File down the head to cover surfaces...

Michael Brisebois
I look forward to Your Pictures.
 
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