Sealing up valve covers

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Texas Red

Texas Red

Old Flunky
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Bought some neoprene valve cover gaskets trying to seal up my 318 in Project 53 truck of mine. I Have to run stock valve covers due to the power brake booster
being so close to my valve cover. Dug around in my spares and came up some super clean 360 valve covers from a previously parted out engine. wire buffed the gasket sealing surface, used some Permatex high tack on the valve cover side to stick the gasket to the valve cover and installed.
I dont think the gaskets are crap because I am running the very same gasket on my Duster 410 engine without any leaks but have some quality welded aluminum valve covers I obtained from Mancini Racing and have zero leaks on it. I dont think the factory stamped steel valve overs have enough clamp down power to make that happen in comparison to the aluminum ones I am running on my Duster engine. I hate to even think about using high tack on both sides of the gasket but space is a problem over close to the brake booster side.... Oil gangs up in the corners no matter what you do........... Any ideas?????? Thanks everybody Texas Red
 
Did you make sure the bolt holes were not deformed and straighten them out if they were? That said, I've had the absolute BEST luck using good old cork gaskets. They seal every time.
 
I have both stamped steel and aluminum covers on my two 440s and I have found that the gaskets will relax and become slightly loose after sitting couple of hours (around a 1/2 to 3/4 turn) and I will retorque several more times over several days (at least once a day) till the torque stabilizes at the factory torque setting. Have had no leaks doing it that way.
 
Use brake parts cleaner to clean oil film from parts to be sealed.

Felpro cork gaskets, black silicone gasket maker (RTV) on both sides of gaskets. Light film gasket maker on valve cover and the porous cast heads. Assemble, let cure over night before adding oil or starting the engine.

Never Leaks

Want to get it apart again? Spray brake parts cleaner on the gasket area, let it soak for 15 minutes > keep it wet.

That softens the RTV so you can get it apart again.


☆☆☆☆☆
 
Im a big proponent of " let the gasket do it's job "
I often assemble oil pans (on stand) with only 4 pea sized dabs of, now "Right Stuff" where the gaskets meet.
(All regular RTV went in the garbage)
Same with intake, no slather of goop, just 4 pea dabs where gskts meet.
I do use 3M Weatherstrip Adhesive to hold a valve cover gasket to the cover, same to hold oil pan side gskts to block, from under the car, and timing cover gsk, water pump gaskets etc, only to hold the gasket in place during assembly, not to seal, - let the gasket do it's job.

RTV works as long as it ADHERES to the surfaces .
You go around "snugging" a RTV gskt, you often break the adhesion and cause a leak, - been there too often, fixing other folks "goop" jobs.
Professional mechanics have a time limit and customers have expectations. Having them wait till the next day for something to "cure", that likely shouldn't have been used is less than satisfactory.
We clean, glue v/cover gskt to cover, install, drive it out and away it goes.

GM tried to use GMS (orange RTV) for pans, valve covers, all the tin, auto trans pans, - was the biggest "recall" in gm history.

Just my experience .
Good Luck .
 
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Inertia said:
Im a big proponent of " let the gasket do it's job "
I often assemble oil pans (on stand) with only 4 pea sized dabs of, now "Right Stuff" where the gaskets meet.
(All regular RTV went in the garbage)
Same with intake, no slather of goop, just 4 pea dabs where gskts meet.
I do use 3M Weatherstrip Adhesive to hold a valve cover gasket to the cover, same to hold oil pan side gskts to block, from under the car, and timing cover gsk, water pump gaskets etc, only to hold the gasket in place, not to seal, - let the gasket do it's job.

RTV works as long as it ADHERES to the surfaces .
You go around "snugging" a RTV gskt, you often break the adhesion and cause a leak, - been there too often, fixing other folks "goop" jobs.
Professional mechanics have a time limit and customers have expectations. Having them wait till the next day for something to "cure", that likely shouldn't have been used is less than satisfactory.
We clean, glue v/cover gskt to cover, install, drive it out and away it goes.


Just my experience .
Good Luck .
Click to expand...
The only thing I ever use on any valve cover gaskets is 3M yellow weather strip in just a few places to hold it in place and let it dry good before I put it on. At least that way, when you flip the cover upright, the gasket stays on place.
 
Use the white Permatex Hi-heat thread sealer on the vc bolts. Stops oil from wicking up the threads. I wasn't a believer until I tried it. I now use it on all timing cover/water pump bolts too.

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4spdragtop said:
I did check, but can't remember if they are open or not. Regardless, I would always have "leaks" around the bolts. On my latest build I used the permatex and it sealed them right up. Dry as a popcorn fart now.
Click to expand...
It wouldn't surprise me if they might leak regardless since the holes make that area of the valve cover rail pretty thin.
 
First off, make SURE the valve cover is able to tighten down properly, and isn't interfering with the intake manifold... many aftermarket manifolds have taller runners and meatier flanges that contact the lip of the valve cover, preventing it from tightening down fully. Yes, even the stock stamped covers can have this issue. Usually a little judicious grinding in selected areas of the valve cover lip solves the problem.
Also, are you using the little triangular valve cover washers? They're pretty much a necessity on the stamped v.c.s- they help to distribute the load without as much distortion. Even the factory was using them after time went on...
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https://www.jegs.com/i/Mopar-Perfor...m_term=4581596255650123&utm_content=Evergreen
 
I just use the gasket also and maybe a light dab of something to hold it in place. Weather strip adhesive works well. Like Rusty said.
 
Texas Red said:
Bought some neoprene valve cover gaskets trying to seal up my 318 in Project 53 truck of mine. I Have to run stock valve covers due to the power brake booster
being so close to my valve cover. Dug around in my spares and came up some super clean 360 valve covers from a previously parted out engine. wire buffed the gasket sealing surface, used some Permatex high tack on the valve cover side to stick the gasket to the valve cover and installed.
I dont think the gaskets are crap because I am running the very same gasket on my Duster 410 engine without any leaks but have some quality welded aluminum valve covers I obtained from Mancini Racing and have zero leaks on it. I dont think the factory stamped steel valve overs have enough clamp down power to make that happen in comparison to the aluminum ones I am running on my Duster engine. I hate to even think about using high tack on both sides of the gasket but space is a problem over close to the brake booster side.... Oil gangs up in the corners no matter what you do........... Any ideas?????? Thanks everybody Texas Red
Click to expand...

You might check to see if the rails on the heads are flat front to back.
I have had to deal with heads that had an 1/8 rise in the center.
 
I always check the vc naked on the head, looking for wobbles side to side or end to end. And I chase the vc holddown bolt holes, (if I'm not using vc studs, which I usually do). Rtv or sealer in the bottom of the boltholes can give false torque readings.
Then I use gasket cement of choice to bond the gasket to the cover, and then use bigger wider load spreaders that I make myself, out of 1/8 aluminum. The spreaders are necessary on the stamped aluminum (paper thin) moroso covers.
 
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Yep I'm getting what you're saying. The ONLY leaks were coming up bolt holes and I took @str12-340 advice and used Permatex and it solved it. I guess I'll have to chk 318 heads I have on shelf to see if holes are open or not. I used thick gaskets, can't remember if Fel or MP.
I can't add anymore than what has been posted by everyone else except the Permatex worked lol.
Bodyperson said:
I'm not sure you are picking up what I am laying down Steve. The sealing of the oil needs to be before the fasteners.
Click to expand...
 
4spdragtop said:
Yep I'm getting what you're saying. The ONLY leaks were coming up bolt holes and I took @str12-340 advice and used Permatex and it solved it. I guess I'll have to chk 318 heads I have on shelf to see if holes are open or not. I used thick gaskets, can't remember if Fel or MP.
I can't add anymore than what has been posted by everyone else except the Permatex worked lol.
Click to expand...
It doesn't take much clamping force to hold oil back with a good valve cover. I've re-used glued to valve cover cork gaskets double stacked over and over.
 
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