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Discussion Starter #1
Heres an age old question for the SBC... whats a good combination of valve covers and gaskets to get the damn covers to stop leaking?

Im currently using a set of Edelbrock covers that came free with my heads. Theyre nothing special, Im pretty sure theyre steel. With these covers Im using gaskets that are made from a dense foam type material, I forget what brand. I have the gaskets secured to the covers with RTV silicone for easy removal and installation. However, no matter what I do they continue to seep oil, mainly from the back of the cover (towards the firewall), all over my cylinder heads. I can't stand having leaks, especially from my brand new motor! :crazy: :laughing:

Im sure there is someone out there that has come up with a good setup that doesnt leak, so I figured I'd ask.

I did some searching online and came up with one possibility....

~Fel-pro's top gaskets, theyre molded Silicone rubber.
http://www.summitracing.com/parts/FEL-1628/
~Trans-dapt spreader bars to spread the bolts tension over more of the cover.
http://www.summitracing.com/parts/TRD-4993/

I also considered getting new Cast Aluminum covers if you guys think theyd be less likely to leak.

Also, one other thing that may be worsening my issue is my plug wire looms. I have these looms listed below... theyre secured with the two lower valve cover bolts. I dont know if maybe this is messing with the torque of the bolts......?

http://www.summitracing.com/parts/MFY-5035613/


I'd appreciate any advice or shared experiences. I'd love to be able to keep my engine a little cleaner, but I dont want to just start throwing money around at parts that aren't going to work! :D
 

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There is nothing wrong with steel valve covers.
The trick to leak less covers are to ensure the flanges and bolt holes are flat.

After making sure the flanges and bolt holes are clean and flat.
Smear a bead of RTV about 1/8" thick on each cover.
I let the RTV set for a minute or two before I press the gaskets in. I use fel-pro gaskets. If you don't have flange stiffeners
get some! If you don't you will never get the covers to seal.

Don't over torque the covers and you should not have any problems.

BoL...
 

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Working under the assumption your current covers are tweaked......

Gluing the gasket on one side is a good idea, but you've got to let the RTV cure while setting on a flat surface with a few pounds on top of the covers. I've seen them glued weirdly and that caused leaks.

Load spreaders are your friend. The 5 inch long versions, not the one inch long versions.

Cast aluminum covers are less prone to warping but if you're bending a quality steel cover (edelbrock, moroso, etc) then lay off the prybar buddy! :laughing:

Common causes for "back of valve cover" leaks are the rear oil pressure port being 1/4 turn from tight, or a wire trapped under the back of the covers.

Honestly, a cork gasket ought to do fine for what you're asking. Maybe these weird foam gaskets are to blame?? I'm not really picturing what you're speaking of.

Good luck with your project
 

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Lots of folks make the mistake of thinking tighter-is-better so they lay on the valve cover bolts and get them way too tight.

The actual recommended torque on valve ocver bolts is next to nothing.

:thumbsup:
 

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The OE heads have cast, rough sealing surfaces, and can hold a lot of the original gaskets, especially in hard to reach areas. Be super-duper sure they're totally clean. If you're not bleeding they're probably not clean enough. :cheers:

And as noted, a 1/4 inch drive nutdriver/screwdriver deal is the tool to tighten a valve cover, possibly combined with a 1/4" drive ratchet with one finger worth of pressure. It is certainly not a 3/8 drive ratchet, by the time you generate enough torque to make a 3/8" drive perform ratchet action you're too tight.
 

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Discussion Starter #6
The OE heads have cast, rough sealing surfaces, and can hold a lot of the original gaskets, especially in hard to reach areas. Be super-duper sure they're totally clean. If you're not bleeding they're probably not clean enough. :cheers:

And as noted, a 1/4 inch drive nutdriver/screwdriver deal is the tool to tighten a valve cover, possibly combined with a 1/4" drive ratchet with one finger worth of pressure. It is certainly not a 3/8 drive ratchet, by the time you generate enough torque to make a 3/8" drive perform ratchet action you're too tight.
Thanks for all the input guys.

Theyre not OE heads, theyre Edelbrock aluminum heads. I don't think I overtightened, I was very concious of the amount of torque I was applying when I installed them because Ive seen what can happen.



Load spreaders are your friend. The 5 inch long versions, not the one inch long versions.
Good to know. I had never heard of them until I did a google search on valve cover leaks the other day. I'll definitely pick up some 5in ones like you said.

Cast aluminum covers are less prone to warping but if you're bending a quality steel cover (edelbrock, moroso, etc) then lay off the prybar buddy!
I swear I was gentle! lol The only thing is I had a valve train issue early on (<100miles) after getting the motor in the car. I had to take the covers off and reinstall numerous times... maybe at one point I tweaked them without realizing it.

Common causes for "back of valve cover" leaks are the rear oil pressure port being 1/4 turn from tight, or a wire trapped under the back of the covers.
The only thing is its on both sides. Also, it doesnt seem to be running down from the oil pressure sensor port.

Honestly, a cork gasket ought to do fine for what you're asking. Maybe these weird foam gaskets are to blame?? I'm not really picturing what you're speaking of.
Yeah, I had never seen valve cover gaskets other than rubber or cork. These are like a dense spongey material that came with the covers.
 

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no one has mentioned that there is oil drain holes at the back of the head inside the rocker arm area if these get blocked by sludge ,ditd or a piece of the ols gaskets the oil will back up and fill the ares up above the gasket line, then it will leak ,check itout
 

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Discussion Starter #8
no one has mentioned that there is oil drain holes at the back of the head inside the rocker arm area if these get blocked by sludge ,ditd or a piece of the ols gaskets the oil will back up and fill the ares up above the gasket line, then it will leak ,check itout
Definitely good to know, and I will take a look. But theres only about 550miles on the motor and all the parts, other than the block are new, so hopefully nothing is that sludgey lol, and this is the first set of gaskets used so far. Also, the valvetrain issue I was having was I wasnt getting enough oil through the pushrods to the rocker arms... because of this there were a couple occasions last fall that I had the motor running with the valve covers off while I was working on it. While I was doing this I didnt notice any blockages, everything seemed to be flowing fine.
 

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Definitely good to know, and I will take a look. But theres only about 550miles on the motor and all the parts, other than the block are new, so hopefully nothing is that sludgey lol, and this is the first set of gaskets used so far. Also, the valvetrain issue I was having was I wasnt getting enough oil through the pushrods to the rocker arms... because of this there were a couple occasions last fall that I had the motor running with the valve covers off while I was working on it. While I was doing this I didnt notice any blockages, everything seemed to be flowing fine.
With a new motor you shouldn't have any drainage problems.
The best valve covers are the oem sbc aluminum L82 covers.
They look good and have oil drippers inside and also a lip around the gasket flange on the inside preventing oil from running onto the top gasket seal surface. I haven't seen any aftermarket covers designed this well.

If using stamped steel covers, these gaskets pictured work well, a little pricier than most. They have a solid steel core and ribbed silicone surface. The only thing I would add to the instructions is to clean and blowout the bolt holes with lacquer thinner and put rtv in those holes after putting the valve cover on but before installing the bolts. The torque is listed in the instructions. As far as your lack of oiling, try using a lower viscosity oil, there is really no need to run a 50 weight these days.

The lowest is the original GM load spreader
The middle is the Felpro supplied spreader
The spreader on the cover is from a early 80's gmc truck
Doesn't leak even after 1 year.











 

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Good to know. I had never heard of them until I did a google search on valve cover leaks the other day. I'll definitely pick up some 5in ones like you said.
Car trivia.......in addition to "turbo" mufflers, musclecar builders owe a nod of thanks to the corvair for.......

Those long load spreaders. Yep, that classic staple of the Mr Gasket store display is just a chromed corvair load spreader.
 

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Discussion Starter #11
The best valve covers are the oem sbc aluminum L82 covers.
They look good and have oil drippers inside and also a lip around the gasket flange on the inside preventing oil from running onto the top gasket seal surface. I haven't seen any aftermarket covers designed this well.
Yeah, my car was actually originally an L-82 and I still have the original valve covers. I could clean them up and paint them. However, I'm not sure if they'd clear my rocker arms. I'm using Crane Cam Gold Race Extruded rocker arms.... theyre pretty big!

If using stamped steel covers, these gaskets pictured work well, a little pricier than most.
Those look real nice, Ill look into getting a set for sure.

As far as your lack of oiling, try using a lower viscosity oil, there is really no need to run a 50 weight these days.
No, that was actually a whole nother issue lol. I fixed that right away. There was an issue with the lifters I was using, and when they were at peak lift oil was sneaking out around them rather than going straight through them and up the pushrods to the rocker arms. I was getting oil, just not as much as I should. I swapped the lifters and started it without the valve covers and it flows like a raging river now lol.


I like your ideas about the gaskets and RTV in the bolt holes, however, I have one concern. I posted a link above that brings you to the listing on Summit of the spark plug wire looms I use. The type that I use bolt to the lower two valve cover bolts on both side. Basically you put them on the valve cover and the valve cover bolts run down through the looms and into the valve cover and head. Do you think this will change the needed torque for the valve cover bolts???

Car trivia.......in addition to "turbo" mufflers, musclecar builders owe a nod of thanks to the corvair for.......

Those long load spreaders. Yep, that classic staple of the Mr Gasket store display is just a chromed corvair load spreader.
lol nice!
 

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Most aftermarket heads raise the valve cover gasket surface so that short covers have similar clearance to talls with stock heads.

You don't need drippers with roller rockers, those are to keep the OE ball fulcrums from overheating, so if they're the only clearance issue grind em out.

Finned aluminum is totally the way to go regardless if it's L82 or aftermarket. Ton of corvette hipo heritage there. Aluminum also eliminates the need for spreaders.

Your lower bolt situation.....When GM did the same thing they used a stud with a flanged nut permanently attached so you could install/torque the valve cover like it had a bolt, then attach the loom using the stud.

Good luck!
 

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THE BEST gaskets are the Fel-Pro Blue Silicon. They're a bit more expensive, but totally worth it.

They have solid spacers for the bolt hole so you can't over-torgue, and they're re-usable. A little taller than OEM cork.

I've been running them on my L-82 for 15+ years with absolutely no leaks.

The only way to go IMHO!
 

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Discussion Starter #14
THE BEST gaskets are the Fel-Pro Blue Silicon. They're a bit more expensive, but totally worth it.

They have solid spacers for the bolt hole so you can't over-torgue, and they're re-usable. A little taller than OEM cork.

I've been running them on my L-82 for 15+ years with absolutely no leaks.

The only way to go IMHO!
I think those are the ones I was looking at on Summit... they're like $47 or something, that'd be worth it. I'll probably order them.
 

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FYI
The blue silicone are the Perma Dry and the black silicone pictured above are the one step above, Perma Dry Plus

From Felpro website
Federal-Mogul's Fel-Pro® brand offers two lines of premium valve cover gaskets: PermaDry® and PermaDryPlus®.

PermaDry gaskets, made of molded rubber, are excellent as replacement parts on engines that were originally equipped with molded-rubber gaskets. PermaDryPlus gaskets have a rigid carrier and molded-silicone rubber sealing bead. They are designed and built specifically to seal difficult problem leaks.
http://www.federalmogul.com/en/Afte...utions/Products/LeakRepair/Fel-ProValveCover/

Blue Silicone
http://www.federalmogul.com/en/Afte...oducts/LeakRepair/Fel-ProValveCover/Permadry/

Black Silicone/steel core
http://www.federalmogul.com/en/Afte...ts/LeakRepair/Fel-ProValveCover/Permadryplus/

From Summit
http://www.summitracing.com/parts/FEL-VS12869T/

Cheaper at Advance Auto
http://shop.advanceautoparts.com/we...9783646-P_107_R|GRPGASKAMS____?zoneAssigned=1
 

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Discussion Starter #16
Thanks man, good info.

Looking at Summit though I cant figure out why the PermaDryPlus are cheaper than the regular PermaDry...wouldn't the top end model be more expensive? lol Heres what Im talking about:

http://www.summitracing.com/parts/FEL-VS12869T/

http://www.summitracing.com/parts/FEL-1628/

What do you think?

Also in the picture in the first link, gaskets #12869, what are those small things that come with the gaskets? They almost look like load spreaders....
 

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A simple trick I've used for years on all sort of things like valve covers, oil pans, front covers, etc, is this.

I clean the bolt threads with i.e. carb spray, solvent, etc,
and either air dry thoroughly or dry with compr air.

I use carb spray thru the straw to clean out the bolt holes,
then blow them clean with compr air.

I use a dab of blue Loctite on the bolts and torque them,
then let things set overnite before starting the engine.

Very seldom get even a seep doing it that way.
 

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Thanks man, good info.

Looking at Summit though I cant figure out why the PermaDryPlus are cheaper than the regular PermaDry...wouldn't the top end model be more expensive? lol Heres what Im talking about:

http://www.summitracing.com/parts/FEL-VS12869T/

http://www.summitracing.com/parts/FEL-1628/

What do you think?

Also in the picture in the first link, gaskets #12869 what are those small things that come with the gaskets? They almost look like load spreaders....
Yes they are load spreaders on the first pic, the 12869T gaskets are for street use. The 1628s' are more pricey because they are primarily for race applications.
I use the 12869Ts', I've removed & reinstalled them a couple of times with no problems and no leaks. Remember to install them dry.
 

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Discussion Starter #19
Yes they are load spreaders on the first pic, the 12869T gaskets are for street use. The 1628s' are more pricey because they are primarily for race applications.
I use the 12869Ts', I've removed & reinstalled them a couple of times with no problems and no leaks. Remember to install them dry.
So for my engine setup with aftermarket heads and valve covers would the race application be more fitting? I primarily drive it on the street but it will be going to the strip on weekends.
 
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