New Valve Cover Gaskets
Thread Starter
Melting Slicks
Joined: Mar 2009
Posts: 2,885
Likes: 1
New Valve Cover Gaskets
What do you guys typically do when installing new gaskets for the valve covers? Do you finger coat the gaskets with oil first or some other product? Or do you just install them without anything on them? I'm trying to make sure I get a better seal, if possible. Got the gaskets from NAPA and they're for a stock '78 L48.
Also, what number should these be torqued down at?
Thanks!
Also, what number should these be torqued down at?
Thanks!
Race Director
Joined: Jun 2000
Posts: 10,046
Likes: 675
From: FL
I install dry, hand tighten, run for a while and then retighten. I use Mr. Gasket Ultra Seals (about $9 a pair). I also have studs instead of bolts and aluminum valve covers. If you have steel valve covers, make sure you use load spreaders so you don't warp the covers, which will cause leaks.
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
Rubber gaskets are coated w/ oil.
If stock L-48 are cork, dry will work for awhile anyway. Many use Permatex on cork.
I never torque them & they don't leak. Book shows 55 in./lb.
That's mainly what the repair books are good for- torque specs.
If stock L-48 are cork, dry will work for awhile anyway. Many use Permatex on cork.
I never torque them & they don't leak. Book shows 55 in./lb.
That's mainly what the repair books are good for- torque specs.
Melting Slicks
Joined: Feb 2006
Posts: 3,428
Likes: 5
From: Japan
I have the original sheetmetal covers on my '70. I installed the Fel-Pro cork gaskets by cleaning the rails on the covers thoroughly then attaching the gaskets to the covers with a thin bead of yellow 3M weatherstrip adhesive. While the glue dried I cleaned the rails on the heads with lacquer thinner (Brakleen, acetone, or some other such solvent works as well).After that I installed them onto the heads with the stock-type load spreaders just tightly enough to close any gaps all the way around the cover which I checked with an .0015" feeler gage. They don't leak.
Thread Starter
Melting Slicks
Joined: Mar 2009
Posts: 2,885
Likes: 1
My covers didn't have any load spreaders under the bolts. (Bubba strikes, once again?) I understand about not crimping the flanges if bolts are too tight without spreaders. But what if I tightened bolts enough (less than torque spec) to hold me for a couple weeks, order a set of load spreaders and then re-bolted with the spreaders on later and then torqued to spec?
Btw - cork gaskets and the stock steel (blue) covers.
Btw - cork gaskets and the stock steel (blue) covers.
Drifting
Joined: Feb 2005
Posts: 1,879
Likes: 38
From: Los Gatos CA
Mating surfaces must be flat and clean. Check around the fastener holes and use a ball peen hammer if necessary. Neoprene is more forgiving than cork, but either will work. Over torqueing will cause leaks, so just snug 'em up evenly. Easy money...
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Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
The stamped steel valve covers need to have the [sealing] rail surface flattened well...especially at the bolt hole areas...before you install new gaskets. Put the rail of the cover upside-down on a flat piece of steel/metal (not wood) and use a small hammer to flatten any bent/dented/deformed areas on each cover. Then clean the joint surfaces on head and cover with a good cleaner [paint thinner, etc.]. Buy Fel-pro cork/rubber combination gaskets (or other brand of similar construction) and install bolts lightly hand tightened/snugged-down so there is no rail deformation. They'll seal.
Drifting
Joined: Apr 2008
Posts: 1,540
Likes: 51
From: Lexington Park Maryland
That's how I do it. That way you can take the covers on and off without the gasket falling off.