valve covers that won't leak - ??

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ScampMike

ScampMike

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probably a semi-stupid question - and at the risk of starting something on here.. does anybody have suggestions/experience as to which covers and gaskets to use on a small block that won't leak?
 
My stock steel valve covers and felpro rubber gaskets didn't leak even after taking them off and putting them on a few times
 
What are you using?

overall I've had great luck with stock steel ones, unless they have been tweaked and stretched around the bolt holes from overtightening... then you'll never get them to stop leaking. Look at the mounting surface of what you're using and see if it's straight and flat, if it's not, find a new set.

I had horrible luck with a cast aluminum set until I realized they had a lip that was getting hung up on the intake runner causing them to not seal against the gasket completely.

I typically look for cork gaskets, usually felpro, but I think summit has "double thick" cork ones avail from somebody too. I've used those on a car that I had the VC's off frequently for valve adjusts with good luck resealing.

Hope this helps.
 
The Moroso blue ones..best I ever used have had covers on/off numerous times no leaks..
 
It's all in the material you use and how/if you seal and tighten them.
Hate cork because it always ends up wet around the gaskets no matter what you do.

Also notice that stock iron heads are not flat but slightly raised if you look at them front to back.
In my own experience they are raised as much as 1/4 in the center and it makes sealing cast a PIA, but still can be done with thicker or multiple gaskets.

I use nothing but the black rubber on OE style covers.
Clean them up and straighten the sealing surface, then a 1/8 bead of RTV between the cover and gasket staying just on the inside of the bolt holes.
Then 1/8 bead of RTV down the center of the block side flattened and spread with a finger still going on the insides of the bolt holes.
Put it on and just lightly snug the bolts and let it sit for a few hours like that.
Then come back and tighten them down till you just see the rubber start to move around bolts and stop there.
I never have cover leaks doing it this way.

One the magnum with cast covers I used the Magnum tan silicone gaskets that are steel inside and still use a tiny bead of RTV on both side of those. (less RTV than OE covers, but I do them the same way)

BTW, I do consider myself better than the average bear at sealing things up, and my motor still looks like this months after the engine install.

MagnumswapLA.jpg
 
joeboy said:
What are you using?

overall I've had great luck with stock steel ones, unless they have been tweaked and stretched around the bolt holes from overtightening... then you'll never get them to stop leaking. Look at the mounting surface of what you're using and see if it's straight and flat, if it's not, find a new set.

I had horrible luck with a cast aluminum set until I realized they had a lip that was getting hung up on the intake runner causing them to not seal against the gasket completely.

I typically look for cork gaskets, usually felpro, but I think summit has "double thick" cork ones avail from somebody too. I've used those on a car that I had the VC's off frequently for valve adjusts with good luck resealing.

Hope this helps.
Click to expand...
stock type steel covers and rubber gaskets on aluminum heads... I have the engine out right now so I figure this is the time to get after the oil leak issue I am having... rear of both covers - go figure... hey, at least it's not the pan gasket like I thought! :thumbsup:
 
TrailBeast said:
It's all in the material you use and how/if you seal and tighten them.
Hate cork because it always ends up wet around the gaskets no matter what you do.

Also notice that stock iron heads are not flat but slightly raised if you look at them front to back.
In my own experience they are raised as much as 1/4 in the center and it makes sealing cast a PIA, but still can be done with thicker or multiple gaskets.

I use nothing but the black rubber on OE style covers.
Clean them up and straighten the sealing surface, then a 1/8 bead of RTV between the cover and gasket staying just on the inside of the bolt holes.
Then 1/8 bead of RTV down the center of the block side flattened and spread with a finger still going on the insides of the bolt holes.
Put it on and just lightly snug the bolts and let it sit for a few hours like that.
Then come back and tighten them down till you just see the rubber start to move around bolts and stop there.
I never have cover leaks doing it this way.

One the magnum with cast covers I used the Magnum tan silicone gaskets that are steel inside and still use a tiny bead of RTV on both side of those. (less RTV than OE covers, but I do them the same way)

BTW, I do consider myself better than the average bear at sealing things up, and my motor still looks like this months after the engine install.

View attachment 1714989465
Click to expand...
hum... fabricated covers.. whos' you got there?
 
TrailBeast said:
I use nothing but the black rubber on OE style covers.
Clean them up and straighten the sealing surface, then a 1/8 bead of RTV between the cover and gasket staying just on the inside of the bolt holes.
Then 1/8 bead of RTV down the center of the block side flattened and spread with a finger still going on the insides of the bolt holes.
Put it on and just lightly snug the bolts and let it sit for a few hours like that.
Then come back and tighten them down till you just see the rubber start to move around bolts and stop there.
I never have cover leaks doing it this way.
Click to expand...


holy crap thats a lot of steps... i use the ones i listed above, bolt them on and go. and they don't leak.. screw having to wait for permatex to dry..lol
 
If they aee OEM style Mike, the problem may lie in the mount holes being "worn". Similar to how oil pan holes need to be "reflattened/straightened" ??
Someone posted a link a while back. I believe it was regarding VC gasket quality and Summit (I think) had them.
 
abodyjoe said:
holy crap thats a lot of steps... i use the ones i listed above, bolt them on and go. and they don't leak.. screw having to wait for permatex to dry..lol
Click to expand...

It's a lot of never leaks also.
Personally I put them on and tighten them down to where I want them, but to err on the side of caution it's not a bad idea to let the RTV set up a little before putting pressure on so the gasket doesn't squirt out from the silicone surfaces.
 
ScampMike said:
hum... fabricated covers.. whos' you got there?
Click to expand...

Were you asking who made the fabbed covers I have?
Don't know, as I got them from another member and there was no original info with them.
All I knew was they had good thick rails, baffles and a vent hole on each one.(one for fresh air in, and the other for PCV)
You can find them on all the normal racing places and on Ebay, but I got these for about 1/2 what they charge.

Magnums have a machined flat surface on the heads instead of cast rough like OE heads so they went on real nice.
I had my own solution when I used them on my old OE heads, but using these with OE heads pretty much requires two gaskets on each one or the thick ones to compensate for the heads not having the flat surfaces for sealing.
(remember, cast covers are flat and straight and OE iron heads are not.
 
The first ones were OEM on tons of GM products.
Never needed or used the bars, but I can see that they could help distribute the load a bit more.

My neighbor was bitching over there across the street one day and I asked him what was up, and he said his 3rd set of cover gaskets were leaking.
I walked over and saw all the bolts tightened down so far that the covers were bent and gasket material squeezed out the sides and split around every bolt.
Uh, there's your problem. :D

It didn't help that they were super cheapie chrome aftermarket and thin as paper almost.
 
The way that I've dealt with bent/warped holes on stock valve covers is I take a wood block, like a 2x4, and sand a radius on it that fits the top of the valve cover where the bolt goes. Then I turn the valve cover upside-down, press it over the bolt hole against the radius, and hit the hole with a ball peen hammer. This flattens and even curves the hole upward slightly. Makes it last few a few more times taking it on/off.

In addition to doing that I bet those triangle washers or longer hold-down pieces would work pretty well if needed
 
I just installed a cheap Felpro set. VS50184R. I was setting the valves and tired of the leaks on the black wrinkle covers. So put rtv on lip of valve cover put gaskets in and let the rtv setup before installing.
Thick.as hell.020 and very stiff.
Old ones were 5 yr old rubber felpro.
Im thinking rtv on the threads of bolts would also help stop seepage?

20170718_201856.jpg
 
I ended up buying a set of Holley Fabricated valve covers and using gaskets that were suggested by a local shop - and of course I don't remember the name of them.. I know they were expensive as gaskets go, somewhere around $50 for the set and they had a persons name - like Bob Smith's hardcore gaskets or some **** like that. I had to grind the valve covers on the inner (toward the intake) edges because the intake runners sit up high enough that the covers wouldn't sit flat to the heads. I also had to trim the gaskets just a tad, they had the positioning tabs on them, those had to go, and I had to "relief" the intake touching edge of each gasket to get them to sit flat. I used black RTV on the cover and not on the head and tightened the bolts using a "star" pattern to "good and snug" spec. :thumbsup: So far so good - not leaking, and I am happy with how they look.
103_4601.JPG
 
I run Mopar Performance valve covers on my 273, but I'd have to say I like the stock ones better... I had to grind off the tabs on the top of the runners on my Torker 340 intake so they would even fit without leaking..

IMG_0071.JPG
 
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Stock steel covers in good condition, with good Moroso or Mopar steel-core rubber gaskets will work on almost anything. You're going to have trouble with any other type of cover on stock heads, because the gasket surfaces are nowhere near flat. Cast aluminum covers are nearly impossible to get to seal on stock heads because of this. The stiff aluminum won't bend to conform to the surface of the head. Cast aluminum or good stock covers will always work on aftermarket heads where the gasket surface is machined. I still like the steel-core Moroso or Mopar gaskets here.. You shouldn't need any sealer either. But as others have said, check to make sure those aluminum covers aren't getting hung up on the intake manifold. Some even hit on exhaust manifolds.
 
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69_340_GTS said:
Stock steel covers in good condition, with good Moroso or Mopar steel-core rubber gaskets will work on almost anything. You're going to have trouble with any other type of cover on stock heads, because the gasket surfaces are nowhere near flat. Cast aluminum covers are nearly impossible to get to seal on stock heads because of this. The stiff aluminum won't bend to conform to the surface of the head. Cast aluminum or good stock covers will always work on aftermarket heads where the gasket surface is machined. I still like the steel-core Moroso or Mopar gaskets here.. You shouldn't need any sealer either. But as others have said, check to make sure those aluminum covers aren't getting hung up on the intake manifold. Some even hit on exhaust manifolds.
Click to expand...
The Moroso gaskets leaked like crazy for me. Stock valve covers stock heads. I even made a post about it. Those gaskets are really made for a machined surface head. I wouldn't use them otherwise. And at the very least i'd still seal them to the valve covers.
 
wow...everybody has a different answer.I have never had a cork gasket leak but i have had the more expensive rubber ones "seep" The problem is over tightening and distorting the valve cover.Cork is best if your covers are straight and you drive regularly.The cork needs to be kept wet to seal.Think of a wine cork..that's why they are stored on their side..to keep the cork wet and swollen.
 
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