SB Valve cover gasket

Knebel

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Last year I installed some fabricated valve covers on my Smallblock along with..i think they were edelbrock gaskets, they have only a couple hundered miles on them. I don't know if i haven't tightened them enough or what but they leak!!! It looks like the oil is seeping through the gasket, both sides the same.

I have seen somwhere some expensive reuseable rubber with steel core gaskets advertised as "they never leak and are worth the investment" but can not for the life of me remember the manufacturer or the part number!? does anyone know what I am talking about?

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I personally like using Fel-Pros line of all rubber valve cover gaskets. They create a good seal, durable - and can be applied multiple times. Do not have to worry about carefully inserting and reinserting so they dont break like cork or some thin silicone gaskets.
 
Regardless of which gasket, use some red Permatex form a gasket on both sides to seal them. You may be having issues with the covers being slightly warped from all that welding and not making a good seat. The red stuff fills any gaps and provides a good seal. Be sure to have the mating surfaces free of oil.

Dave
 
see I only put some permatex on the covers and lightly glued the gaskets on. They seem to be seeping all the way around!?

Non of those manufacturers ring a bell... i wonder if it was felpro or moroso or something like that. I just cant remember lol
 
You were seeing the oil "wick" though the gasket. This can be variable as to how much "thin factions" there are in the particular brand of motor oil you are using. It can be slowed with increased "clamping pressure", but once it starts, there's NO stopping it, unless you change brands of oil.

A friend once cussed Castrol GTX as he couldn't get his valve covers to not seep. I ran that idea by my machine shop operative and he mentioned the "wicking" action. He normally bought the brand of oil that was on sale at the auto supply, rather than being loyal to just one. He said, back then, that he noticed that Valvoline would seep, but when he put Pennzoil in, it dried-up. This was in the later '80s.

Some brands of rubberized cork valve cover gaskets have smaller or larger cork particles and/or more or less rubber in their mix. I usually like the smaller cork bits myself, which usually cost more.

In any event, here's the fix I've used with great success. I'll get some black high-heat silicone and coat EACH side of the valve cover gasket with it. Using my index finger to smear a thin coat of it on. Let it cure and do another side until it's all covered. All FOUR sides and maybe the insides of any bolt holes. This can usually take a day or two to happen.

This effectively seals the gasket from any oil intrusion and wicking. Do NOT attach the covered gasket to the valve cover. Just lay it all in place and put it together. This also makes for a quick clean-up/removal when you take things apart again. I use this technique on ALL gaskets in the engine, paper or rubberized cork.

With gaskets with a bead, as intake gaskets, I'll fill in the bead with the sealer, using a Mr. Gasket gasket scraper to smooth it out. This effectively makes it a "Print-o-seal" style of gasket. Sealing is much better. Still easy to remove and clean up.

In the '60s, we chiseled the 3M "yeller" sealer off of the valve covers, where it was used to glue the gasket to the cover (didn't help it seal any better!) and hammered the bolt holes on the covers themselves for a flat sealing surface. But nothing really helped! I suspect that aluminum valve covers sealed better than the stamped steel ones, but I don't know that for sure.

IF you really need the high-heat tolerance of a solid orange silicone valve cover gasket, then you need that type of gasket. For normal stuff, the "sealed gasket" can work very well.

If you're worried about the fabricated valve cover sealing surface, put a straight edge on the sealing surface and see what it looks like. Or put a thin skin of chassis grease on it and lay it against the cyl head to look for "hills and valleys"? But I suspect that's all in pretty good shape.

With any sheet metal valve cover, be sure to use a "spreader bar" with every hold-down bolt/nut. There were some good ones on the middle '80s Chevy small blocks. Rather than the smaller ones that are more like big flat washers, contoured to fit.

Enjoy!
CBODY67
 
i actually found the gaskets, they were moroso. However before i buy those ill check and see if the valve covers are straight and change oil. gotta do that anyways.
 
So I have not gotten the rubbergaskets with steel core yet. I took the valve covers off to add some bilet spark wire looms to it and inspected the gasket. I had a ot of oil accumulation by the bolt hole in the ery back (surprisingy thats where it also leaked the most. the rest of the gasket looked virtually dry. I put it back together and fired it up an holy *** it dripped and dripped out!!! I could get it to stop dripping by tightening a little more but...wth? I got this "Permatex the right stuff" which has worked pretty awesome in a lot of places, should I just use that and put a smal bead on the head surface and around the boltholes and see if that will do? Or do I hae to 100% instal a new gasket?
 
So I have not gotten the rubbergaskets with steel core yet. I took the valve covers off to add some bilet spark wire looms to it and inspected the gasket. I had a ot of oil accumulation by the bolt hole in the ery back (surprisingy thats where it also leaked the most. the rest of the gasket looked virtually dry. I put it back together and fired it up an holy *** it dripped and dripped out!!! I could get it to stop dripping by tightening a little more but...wth? I got this "Permatex the right stuff" which has worked pretty awesome in a lot of places, should I just use that and put a smal bead on the head surface and around the boltholes and see if that will do? Or do I hae to 100% instal a new gasket?


That is good stuff, The black or red form a gasket also works well and probably better for this situation, also check the covers for a bolt head indent, might have to take a ball peen hammer to remove the defect. Also check the bolt holes in the heads for debris, that can keep the bolts from properly seating. Be sure all the bolts are the same length.

Dave
 
should I be using that with a gasket or just use the right stuff on the head surface and then put the cover on?
 
At this point, you might want to forgo cork gaskets and just use RTV to form your own gasket. The cork gaskets tend to wick oil thru the voids in the cork and the latex bonding material that holds the gasket together and there is no good cure for this. Usually they will not leak enough to cause major issues, but on a show quality engine this can be a significant problem, so the RTV is probably your next best bet.

Dave
 
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