Valve cover gaskets

[SirRobyn0]

I've always run cork, really for no other reason other than they rolled out of the factory that way. My method with tin factory covers has always been to peen the covers if needed and run the longest spreader bars I could get. Glue the gasket to the cover and install, unless there is a history of leaking or an obvious flaw in which case I might silicone the engine side (I like right stuff). However my truck started leaking enough oil from the cover gaskets to make an oil burning smell at idle with the A/C on about a month ago. I don't really like the process or meticulousness that one must go though to make cork seal up so I thought I'd try something else. Did a little looking around and settled on the Fel-pro permadry units the ones with the metal core and rubber on each side of the metal. Looked like a good quality product. Well they never really did seal fully. I've smelled it albeit much less every time I've driven the truck since then. At first I thought it was just from residual but over the past week I was able to start to see just a trace amount on the left side.

Today I found the time to take them off. Sure enough there was an area where you could tell oil had seeped past the gasket on the block side. Both sides were doing that. Wished I'd pick up a cheap set of corkers, but I hadn't. I need to drive the truck on Monday so out came the right stuff and thin bead applied to the engine side. To me that sucks. Oh well. Hopefully this will do the trick if not I'll be going back to cork. Curious what other folks have had for experiences with rubber gaskets on tin covers.

Here's a few pics of the covers after reinstalling them, if you can see them in there lol.

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[85Sierra Classy]

I just went through a similar experience as you. I had good success with the Permadry gaskets in other applications so I gave it a shot on my trucks valve cover gaskets. No matter what I did, I couldn’t get them to seal 100%. I just got done replacing them again with a Fel-pro cork style gasket and no more leaks. A little Permatex gasket sealer on both sides of the gasket (not RTV) this time maybe had something to do with it as well. I’m just glad to not smell the burning oil at idle anymore!

 

[PrairieDrifter]

I used the right stuff on my felpro gaskets, haven't had any issue at all. But I did ditch the stamped valve covers for some cast aluminum ones. That's the problem, these old tin covers don't have enough strength in them to make that much gasket seal with 4 bolts in the center.

You can get spreader bars and cork, but you'll just be fixing the same valve cover leak within the year.

Cast aluminum covers are the way to go, and ditch the cork gaskets. They just soak up oil till they can't anymore then they leak.. that doesn't inspire confidence lol.

 

[82sbshortbed]

I've always used cork and no problems.

 

[SquareRoot]

Haven't used cork for like 20 years. Never had a rubber/steel gasket leak.

 

[SirRobyn0]

@PrairieDrifter I agree the tin covers are far from the best at sealing with only 4 bolts, but I've done fine with cork in the past. I have thought about going to cast aluminum but the thing is that as you can see from the pictures the truck is mostly stock. I don't see that to much anymore and would like to keep it that way if I can.

@85Sierra Classy I think it does not help that the head to valve cover gasket surface is not machined on the head side. Not only is it rounded but who knows how even it was from factory let alone 40 or so years later. A soft cork gasket will conform to all that a relatively stiffer rubber gasket with metal in the middle not so much. I should have known better than to try, but I wanted it to work. Guess I'll be seeing if the right stuff will get those gasket to seal up.

 

[Octane]

I 've had rubber gasket leak issues more frequently than cork.Presently I am using the rubber style with the steel core and one cover is sealed.The other has a spot at the bottom that gets a little very slight oil residue down onto the side of the head.I've got long spreader bars on it and have lossened and retorqued a couple of times,last 100 miles now it seems fine.Seeps again and off the gasket comes and I'll use some kind of sealer. Why the factory never machines the head there is the engineers fault.

 

[Octane]

I used the right stuff on my felpro gaskets, haven't had any issue at all. But I did ditch the stamped valve covers for some cast aluminum ones. That's the problem, these old tin covers don't have enough strength in them to make that much gasket seal with 4 bolts in the center.

You can get spreader bars and cork, but you'll just be fixing the same valve cover leak within the year.

Cast aluminum covers are the way to go, and ditch the cork gaskets. They just soak up oil till they can't anymore then they leak.. that doesn't inspire confidence lol.

And the cork gets hard as a rock and oil soaked.About like not even having a gasket on it.

 

[SirRobyn0]

@Octane I completely agree with your thoughts and experiences. I would have gone back to cork gaskets, but since I did not have them, I ran a bead of right stuff on the block side of the gaskets. This has been the first week that I've not smelled the oil in who knows how long so I'm pretty happy about that but pretty disappointed that gaskets costing 3X the price of cork have given me so much trouble. Lesson learned.

 

[bucket]

In the past, I've used Mr Gasket Ultra Seal valve cover gaskets on SBC's with wonderful success. They are a cork type gasket with some type of non-stick coating on them. I've even been able to reuse them.

 

[SirRobyn0]

In the past, I've used Mr Gasket Ultra Seal valve cover gaskets on SBC's with wonderful success. They are a cork type gasket with some type of non-stick coating on them. I've even been able to reuse them.

I'm aware of those, but have never used them. I've pretty much just stuck with traditional cork with spreader bars, both on my rigs and customers rigs, mainly because it's what I'm use to using on older rigs and seal fine for me most of the time. For some reason I decided I wanted to try something new on my rig. I think part of it is that the old hardened cork gaskets are a pain to get off, and lets face it the process to install them and have them work correctly is not the quickest either, so looking for a better way. I was pretty much game to try either the cork coated metal or rubber. If you remember back in the day when all we had was floppy cork or floppy rubber the rule of thumb was cork for best seal, rubber if you plan to take the covers off a lot and want to be able to reuse the gaskets. So for that reason I would have preferred to try the cork coated metal, but none were in stock locally, the rubber was. I reasoned that I'd installed tons of rubber coated metal gaskets in modern engines with very good success, but of course the mating surfaces are completely different. I could clearly see when I lifted the valve covers and then the gaskets off the engine the second time that both sides were seeping from the engine side of the gasket not the cover side. So I think it's just that the round non-machined surface of the head is not a fine enough surface for the rubber to work effectively on.

I like to do repairs one time and have them last. While I'm ok with RTV where it needs to be I do feel that my current scenario is a bandaid, if it fails I may take the leap and try those or I might go back to old fashion cork as I'm not giving up my stock tin covers.

I assume from what you said about reusing them that you don't apply any kind of adhesive or RTV?

 

[bucket]

I'm aware of those, but have never used them. I've pretty much just stuck with traditional cork with spreader bars, both on my rigs and customers rigs, mainly because it's what I'm use to using on older rigs and seal fine for me most of the time. For some reason I decided I wanted to try something new on my rig. I think part of it is that the old hardened cork gaskets are a pain to get off, and lets face it the process to install them and have them work correctly is not the quickest either, so looking for a better way. I was pretty much game to try either the cork coated metal or rubber. If you remember back in the day when all we had was floppy cork or floppy rubber the rule of thumb was cork for best seal, rubber if you plan to take the covers off a lot and want to be able to reuse the gaskets. So for that reason I would have preferred to try the cork coated metal, but none were in stock locally, the rubber was. I reasoned that I'd installed tons of rubber coated metal gaskets in modern engines with very good success, but of course the mating surfaces are completely different. I could clearly see when I lifted the valve covers and then the gaskets off the engine the second time that both sides were seeping from the engine side of the gasket not the cover side. So I think it's just that the round non-machined surface of the head is not a fine enough surface for the rubber to work effectively on.

I like to do repairs one time and have them last. While I'm ok with RTV where it needs to be I do feel that my current scenario is a bandaid, if it fails I may take the leap and try those or I might go back to old fashion cork as I'm not giving up my stock tin covers.

I assume from what you said about reusing them that you don't apply any kind of adhesive or RTV?

Right, no sealant or adhesive of any kind used on the Ultra Seal cork gaskets.

I didn't mention it before because the discussion was mostly about cork gaskets, but several times in recent years I have used the rubber gaskets with steel core. I thought they were the absolute bee's knees, except for the last pair I installed. The ones (Summit brand) I put on my '78 454 leak just as much as the old rotten gaskets I took off. All the other ones (don't remember the brand, but not Summit) that I installed sealed perfectly. It may just be my valve covers.

 

[SirRobyn0]

Right, no sealant or adhesive of any kind used on the Ultra Seal cork gaskets.

I didn't mention it before because the discussion was mostly about cork gaskets, but several times in recent years I have used the rubber gaskets with steel core. I thought they were the absolute bee's knees, except for the last pair I installed. The ones (Summit brand) I put on my '78 454 leak just as much as the old rotten gaskets I took off. All the other ones (don't remember the brand, but not Summit) that I installed sealed perfectly. It may just be my valve covers.

I did the Fel-pro rubber coated metal, those are the ones that leaked on me. I don't know, I just like not smelling burning oil. lol thanks for the info on the cork coated.

 

[Dutch Rutter]

I had a hard time getting mine to seal, aluminum heads, and cast aluminum covers.

Tried cork, tried the felpro rubber with metal inserts (kinda finned looking type) and still no luck.

I ended up trying these from speedway and they solved all my issues. They are a bit softer then the felpro so they change shape better then the felpro. No sealers and no problems since. The corners fit the cast covers better then any others I've found.

https://www.speedwaymotors.com/Spee...l-Core-Valve-Cover-Gaskets-Pre-1986,1872.html

 

[Raider L]

I can appreciate the fact that many of you want to keep your trucks stock. But I have taken a different route as far as how my truck is done and that is I have used more race products than anything else but with a balance of factory parts and methods to.

I have used them all kinds of gaskets and did not find one that held up very long, and have used Permatex and RTV Blue and Red on one side, both sides, valve cover side, engine side, let it get tacky, etc., etc., until that is, I made a trip to one of my favorite race parts machine shops/parts stores and this is what they had.

Moroso has valve cover gaskets made from a blue silicone with metal in the middle. The silicone conforms to every tiny bump and dot on the head metal. They are completely reusable, and you can flip them over and reuse them which is amazing. Just for g. p. I have kept them on one side and have had them off a dozen times and they don't leak a drop and they've been on my heads for years with no leaks.
Now, let me warn you right now....they are expensive like some race parts can be, like about $50 bucks for the two but they are worth it when they will be the last gaskets you'll need! Make sure your heads are clean, there isn't pieces of cast iron missing out of the rib around the edge where the gasket seals, and the valve cover is straight. If all that is okay then these gaskets I'm recommending will be the ones you need.

The part number is Moroso #93020. Let me quote some: Specially designed gaskets are manufactured from 40 durometer silicone rubber, molded over and vulcanized to a rigid steel frame.
The extra strength design will not leak, blow out, or get sucked in like stock or inferior quality aftermarket gaskets.
Superior quality silicone/steel gaskets outlast cork and rubber composite designs to provide years of dependable service, especially when constantly removing and reinstalling valve covers.
Full 3/16" thick.

And let me say again, I've had mine on my engine for years and have had them off and on I don't know how many times and they have never leaked.