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Looking for better valve cover gaskets.

M

MailmanDan

NAXJA Forum User
Location
Riverside, Iowa
I have a 1996 and 1998 xj w/4.0 motors. I have them both out being rebuilt at a local machine shop. I supplied the gasket set from Felpro, but the rebuilder said he prefers the VALVE COVER GASKETS to be OEM, as in his experience, the Felpro ones leak. I said that the OEM ones leak and I would not choose them, let me ask the NAXJA forum what others think. We both agreed that just using Silicone RTV would make a no-leak gasket, but was too good as a cement and too hard to get off when I need to get the Valve Cover off.

So are there any Valve cover Gaskets that do NOT leak and still let you in and out of the Valve Cover without problems?
 
I run "the right stuff" on valve cover gaskets.
 
I think your mechanic is old school and trying to protect his butt! Never had a problem with the Fel-pro's without using any kind of sealant.
After years of using Curil, I have switched to Yamabond whenever sealing is required!
 
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On my 92 I switched to the later style stamped valve cover and run that rubber gasket. I think fel pro also has a perma dry rubber gasket for the early style. Anything is better than the cork crap.
 
There are a couple different kinds. FEL-PRO VS50458R is a steel core with rubber coating and o-rings for the cover bolts, very good, almost identical to OEM. It is for the stamped steel cover on 96-up, might work on earlier style too but I haven't ever tried.
 
ehall said:
There are a couple different kinds. FEL-PRO VS50458R is a steel core with rubber coating and o-rings for the cover bolts, very good, almost identical to OEM. It is for the stamped steel cover on 96-up, might work on earlier style too but I haven't ever tried.
Click to expand...

That's what I just put on my '96 4.0. No leaks yet, but time will tell. Seems very similar to the OEM steel gasket, but with a rubber coating. Fel-Pro claims no sealant necessary, and that if you do put sealant on one of their gaskets, it can actually CAUSE leaks. Proper valve cover bolt torque also seems to be critical to preventing leaks, and the torque spec isn't much. (Something like 75 in/lbs on mine if I recall right.)
 
I ran into an issue where my fel-pro stamped steel/rubber gasket was not thick enough. The metal cup washer/rubber ring assembly would bottom out on the head before compressing the gasket by only .010". Shaved a small amount off the metal cup washer thingy and presto, never leaked since.
 
ehall said:
There are a couple different kinds. FEL-PRO VS50458R is a steel core with rubber coating and o-rings for the cover bolts, very good, almost identical to OEM. It is for the stamped steel cover on 96-up, might work on earlier style too but I haven't ever tried.
Click to expand...

I have put many of these on various jeeps over the years, never had an issue.
 
I've had no trouble with the Fel Pro ones, put on dry and torqued to spec but I reused the factory inserts. Victor-Reinz makes the factory gaskets.
 
I had done this method for years. and people are probly going to say its not a good idea. but it has worked for me for years.
I take two cork gaskets. stick them together with rtv first. let it dry pressed under something.
then when you install it. the cover sits a little higher up (nice for roller rockers for clearance) but it has prevented leaks for years.
 
md21722 said:
I've had no trouble with the Fel Pro ones, put on dry and torqued to spec but I reused the factory inserts. Victor-Reinz makes the factory gaskets.
Click to expand...

Ditto, Fel Pro with factory inserts worked for me also.

I'm kind of anal about clean when I put any new gasket in. I wiped down the head and valve cover sealing surface multiple times with brake cleaner.

I noticed when I took the factory gasket off it kind of stuck, figured the new one wasn't going to stick to an oil covered surface. If you feel the gasket sealing surface it is kind of tacky. Even the old style cork gaskets often have a coating, often asphaltum.

I also cleaned out the bolt holes and put a tiny dab of Loc Tite on the bolts. I don't know exactly why the valve cover bolts come loose, maybe the gasket shrinks, maybe it is the cool down cycles, but I've found many loose over the years on various XJ's.
 
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THANK YOU ALL for the great replies! I appreciate the various experiences and perspectives! I will verify the Felpro Gasket number in the kit I got to be sure that it is the same as mentioned in replies.
 
The latest fel-pro perma-dry gasket didn't seal for me, so I bought the cork gasket and it works great.
 
This is my first rodeo... so when you refer to "factory inserts", what are you referring to? Does the gasket kit come with Felpro "inserts" which are inferior to the "factory inserts" ?
Also, the reply which referred to "the metal cuppy thing" being too thick causing a poor seal, what part is this so I can watch for the problem when I assemble it?
Thanks for your help!
 
MailmanDan said:
This is my first rodeo... so when you refer to "factory inserts", what are you referring to? Does the gasket kit come with Felpro "inserts" which are inferior to the "factory inserts" ?
Also, the reply which referred to "the metal cuppy thing" being too thick causing a poor seal, what part is this so I can watch for the problem when I assemble it?
Thanks for your help!
Click to expand...

If you look at the valve cover, there are something like 11 bolts, there are metal sleeves with rubber bushings underneath them. I believe the idea was to create an even positive seal without overtorquing. I am sure there are better technical names. But I reused the rubber bushings, rather than the the cheaper feeling plastic ones that Fel Pro supplies. If the Fel Pro bushings had thicker heads, I could see them not allowing the gasket to seal well since the torque spec is only something like 84 in-lbs. I didn't measure I just thought the factory ones were of higher quality. The Fel Pro blue gasket itself seems top notch. I have bought them at Auto Zone or NAPA.

Its usually better to go with your guy wants, even if many of us use Fel Pro.
 
8Mud said:
Ditto, Fel Pro with factory inserts worked for me also.

I'm kind of anal about clean when I put any new gasket in. I wiped down the head and valve cover sealing surface multiple times with brake cleaner.

I noticed when I took the factory gasket off it kind of stuck, figured the new one wasn't going to stick to an oil covered surface. If you feel the gasket sealing surface it is kind of tacky. Even the old style cork gaskets often have a coating, often asphaltum.

I also cleaned out the bolt holes and put a tiny dab of Loc Tite on the bolts. I don't know exactly why the valve cover bolts come loose, maybe the gasket shrinks, maybe it is the cool down cycles, but I've found many loose over the years on various XJ's.
Click to expand...

^This^ I kinda had the same train of thought when I did mine and a solid half of the job (at least!) was probably spent on cleaning up the valve cover and mounting surfaces. Sprung for carb cleaner though, because I figured some would get into the oil, and then into the combustion chamber, and hey, if you can use it to clean a carb, it can't be that big of an issue to burn it in an engine, right?

My factory gasket also stuck a bit as well, but I attributed that to it just being old and being on the engine for a while.

Didn't Loctite the bolts down, but I did torque them to spec. If I notice leaks, I'll re-check the torque and remove, Loctite, and re-torque if necessary. Another thing I did do though is torque the bolts down starting in the middle and working my way outwards in a staggered pattern, kinda like a cylinder head. Don't know if that would help or not, but if tightening the bolts on something as thick as a cylinder head can screw the sealing up, imagine something as thin as a valve cover...
 
I will try to explain better about the "metal insert thingy" problem. I kept having a leak at the back of my valve cover. I was torquing the bolts down and noticed I hit a dead stop before I met the torque value. I took the cover off and measured the thickness of the fel-pro gasket compared to the amount the metal thingy bolt bushings protrude out the bottom of the valve cover and the bushings stuck out .005" more than the actual thickness of the gasket. So in essence there was little to no actual squish happening between the two for the gasket to work. I took the bushings to work and removed .010" of an inch off. Never had a problem since.
 
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