Valve Cover Gaskets leaking
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
Valve Cover Gaskets leaking
Hi guys,
I just recently pulled off my valve covers in order to do some cleaning and sprucing up my engine bay. I purchased some good quality Felpro gaskets from Napa made of rubber (I have never had good luck with the cork type). The guy at Napa suggested that I didn't need to use any permatex with these rubber gaskets. I put them on today and I have one side that is leaking all over my exhaust manifold. I know I got them installed properly and have the holes line up etc. I have Moroso valve covers and am using the T bolts. Any suggestions on how to correct this situation? Should I buy another set of gaskets and reinstall using permatex? Could I have over tightened (or not had them tight enough? Any advice would be greatly appreciated. Thx
I just recently pulled off my valve covers in order to do some cleaning and sprucing up my engine bay. I purchased some good quality Felpro gaskets from Napa made of rubber (I have never had good luck with the cork type). The guy at Napa suggested that I didn't need to use any permatex with these rubber gaskets. I put them on today and I have one side that is leaking all over my exhaust manifold. I know I got them installed properly and have the holes line up etc. I have Moroso valve covers and am using the T bolts. Any suggestions on how to correct this situation? Should I buy another set of gaskets and reinstall using permatex? Could I have over tightened (or not had them tight enough? Any advice would be greatly appreciated. Thx
Racer
Joined: Dec 2002
Posts: 319
Likes: 3
From: santa clara ca
I prefer the combination of both rubber and cork. I use gorilla snot only on the valve covers to confirm they will not move. I also hammer the valve cover bolt holes back up using two ball peen hammers from the bottom and i find the spreaders also help.
Racer
Joined: May 2013
Posts: 421
Likes: 6
From: Chicago IL
You can always try torquing down yours a little more and see if it helps.
If that doesn't work, pick up a rubber gasket with a steel core. That is what I did and I was able to eliminate the leak. The nice thing about the steel core is you can torque it down a little tighter and not worry about the integrity of the gasket as much. That along with some good spacers should do the trick.
http://www.summitracing.com/parts/sum-g2301
http://www.summitracing.com/parts/sum-g3434
If that doesn't work, pick up a rubber gasket with a steel core. That is what I did and I was able to eliminate the leak. The nice thing about the steel core is you can torque it down a little tighter and not worry about the integrity of the gasket as much. That along with some good spacers should do the trick.
http://www.summitracing.com/parts/sum-g2301
http://www.summitracing.com/parts/sum-g3434
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
I will try the different type of gaskets. I did try torquing the bolts down a little tighter and that didn't help. Maybe the gasket didn't stay in place between the two lower bolts or something. I am using the spacers you guys mentioned already, so maybe if I try the different type gaskets and use something like the permatex on the valve cover side to help keep them in place, that will solve my issue.
I wish there were a way to get the T bolts torqued exactly the same, but since you can't put a torque wrench on them, there is no way other than trying to turn them the same number of turns to snug them down. Thanks for the the suggestions guys.
I wish there were a way to get the T bolts torqued exactly the same, but since you can't put a torque wrench on them, there is no way other than trying to turn them the same number of turns to snug them down. Thanks for the the suggestions guys.
Melting Slicks
Joined: Jun 2011
Posts: 3,116
Likes: 598
Hi guys,
I just recently pulled off my valve covers in order to do some cleaning and sprucing up my engine bay. I purchased some good quality Felpro gaskets from Napa made of rubber (I have never had good luck with the cork type). The guy at Napa suggested that I didn't need to use any permatex with these rubber gaskets. I put them on today and I have one side that is leaking all over my exhaust manifold. I know I got them installed properly and have the holes line up etc. I have Moroso valve covers and am using the T bolts. Any suggestions on how to correct this situation? Should I buy another set of gaskets and reinstall using permatex? Could I have over tightened (or not had them tight enough? Any advice would be greatly appreciated. Thx
I just recently pulled off my valve covers in order to do some cleaning and sprucing up my engine bay. I purchased some good quality Felpro gaskets from Napa made of rubber (I have never had good luck with the cork type). The guy at Napa suggested that I didn't need to use any permatex with these rubber gaskets. I put them on today and I have one side that is leaking all over my exhaust manifold. I know I got them installed properly and have the holes line up etc. I have Moroso valve covers and am using the T bolts. Any suggestions on how to correct this situation? Should I buy another set of gaskets and reinstall using permatex? Could I have over tightened (or not had them tight enough? Any advice would be greatly appreciated. Thx
Buy these
http://www.moroso.com/catalog/catego...?catcode=38002
If your value cover's surfaces are nice and flat / smooth you can use these without any sealant. I have the stock steel covers which were not perfect so I added light amount to the valve covers only. Nothing on the head. Used valve cover spreaders plates. These are the best I have found that have given me a leak free seal. The steel reinforcing in these gaskets keeps everything in place.
Drifting
Joined: Aug 2010
Posts: 1,839
Likes: 45
From: nassau co. new york
it goes against what I would think but I have had excellent results from the cork felpro gaskets by themselves.i have cheepo valve covers to boot and have had them off quite a few times since the original install.i set them in place with leak lock on the cover end,placed on a flat surface to dry a bit,hour or so,and coated the block end with never seize.you should not have to kill the bolts to make it leak free.p.s. I never use the copper based never seize, just the nickel based stuff and I had rubber gaskets from the po and they leaked.
Burning Brakes
Joined: Jun 2009
Posts: 840
Likes: 4
From: Syracuse IN
The perimiter valve covers are very prone to overtightening. This will deform the metal. Plus the perimiter valve covers are generally cheap in quality. However, if you really want to keep with the old head designs. I have had great luck using the cork with rubber inpregnated gaskets. Clean the mating surfaces very good, I like using acetone to remove all traces of oil. I then use contact adhesive, similar to soft seal adhesive or general trim adhesive. Glue the gaskets, to both the head and valve cover. After about 1/2 hr, tighten slightly of all perimiter bolts. The use of spreader bars on the bolts, help with deflection of the valve cover. Good luck Al
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Team Owner
Joined: Feb 2003
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From: Sitting in his Nowhere land Hanover Pa
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pull it off and make sure the rubber gasket did not twist on you. every rubber gasket I ever had leaked. replaced them with cork and never had one leak
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Did you clean all of the oil off the valve cover and block surfaces before you installed them? If not, the rubber gaskets will try to squish out of the joint, if they have oil on them.
Remove the covers, clean the surfaces with lacquer thinner so there is no oil on them, wipe down the gaskets, too.
If the valve covers are stamped steel (not cast aluminum), you will need to verify that the sealing rails are VERY FLAT...especially at the bolt hole areas. Dimpled cover rails is the #1 cause of leaky valve covers. Also, you should purchase (8) 'load spreaders' [little metal pieces that fit over the cover and under the bolts]; these help to spread the bolt torque more evenly over the cover rails so that dimples don't form.
When you tighten the T-handles, just take them ALL down to 'snug', first. Then tighten them another 1/4-1/2 turn and see if they seal OK. You shouldn't have to crank them down.
Remove the covers, clean the surfaces with lacquer thinner so there is no oil on them, wipe down the gaskets, too.
If the valve covers are stamped steel (not cast aluminum), you will need to verify that the sealing rails are VERY FLAT...especially at the bolt hole areas. Dimpled cover rails is the #1 cause of leaky valve covers. Also, you should purchase (8) 'load spreaders' [little metal pieces that fit over the cover and under the bolts]; these help to spread the bolt torque more evenly over the cover rails so that dimples don't form.
When you tighten the T-handles, just take them ALL down to 'snug', first. Then tighten them another 1/4-1/2 turn and see if they seal OK. You shouldn't have to crank them down.
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
Did you clean all of the oil off the valve cover and block surfaces before you installed them? If not, the rubber gaskets will try to squish out of the joint, if they have oil on them.
Remove the covers, clean the surfaces with lacquer thinner so there is no oil on them, wipe down the gaskets, too.
If the valve covers are stamped steel (not cast aluminum), you will need to verify that the sealing rails are VERY FLAT...especially at the bolt hole areas. Dimpled cover rails is the #1 cause of leaky valve covers. Also, you should purchase (8) 'load spreaders' [little metal pieces that fit over the cover and under the bolts]; these help to spread the bolt torque more evenly over the cover rails so that dimples don't form.
When you tighten the T-handles, just take them ALL down to 'snug', first. Then tighten them another 1/4-1/2 turn and see if they seal OK. You shouldn't have to crank them down.
Remove the covers, clean the surfaces with lacquer thinner so there is no oil on them, wipe down the gaskets, too.
If the valve covers are stamped steel (not cast aluminum), you will need to verify that the sealing rails are VERY FLAT...especially at the bolt hole areas. Dimpled cover rails is the #1 cause of leaky valve covers. Also, you should purchase (8) 'load spreaders' [little metal pieces that fit over the cover and under the bolts]; these help to spread the bolt torque more evenly over the cover rails so that dimples don't form.
When you tighten the T-handles, just take them ALL down to 'snug', first. Then tighten them another 1/4-1/2 turn and see if they seal OK. You shouldn't have to crank them down.
I did clean my valve covers to make sure all the old gasket was scrapped off and all oils residue was removed. The block was free of all gasket material, however I did not clean it to make sure the oil was off. I also inspected the valve covers to make sure they were flat and did not have dimples at the bolt hole area. My valve covers are the steel chrome plated Moroso's and I am also using the load spreaders mentioned.
One thing I did notice though as I was putting the new gaskets on is that they didn't seem to fit exactly perfect and didn't want to lay flat between the bolt holes. I test fitted them by putting the studs in the block and laying the gaskets down and they did not want to lay flat between the bolts (tried to raise up slightly as if the bolt holes in the gaskets needed to be just a hair closer together). The gaskets have one set of holes on one side, and two sets of holes on the opposite side as if they can be used on more than one engine. I know Napa looked up the right gaskets for this engine because I double checked the number. I'll get some new gaskets and give it another try. Thanks
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
Well, I purchased some new valve cover gaskets today and decided to go with the rubber with steel core. I also purchased some high tack Permatex sealant. I took off the all rubber ones I had originally installed and found that the one that was leaking was because the gasket had slipped out of place between the two lower bolts (the bolt holes in the gasket were in the right place, but it still slipped out of place between the bolts). I reinstalled the new ones that were much better quality. I'll let it sit overnight and tomorrow after work I'll fire the engine up and check for leaks. I feel pretty confident I have my problem fixed. I'll let you guys know. Thanks for everyone's help and input. You guys rock !!!
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
Drifting
Joined: Apr 2002
Posts: 1,720
Likes: 19
From: Manhattan Beach Ca
Also for the record I have found the stock type valve covers dont fit properly on alumnimum heads like AFR. I have two sets of covers that still neither fit exactly perfect and seems like they are not wide enough.
I had to go with doubled up gaskets to raise the cover so the edge lip doesnt have any interference with the head. FYI
I had to go with doubled up gaskets to raise the cover so the edge lip doesnt have any interference with the head. FYI
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
Thread Starter
Racer
Joined: Feb 2008
Posts: 357
Likes: 3
From: Madisonville Kentucky
Also for the record I have found the stock type valve covers dont fit properly on alumnimum heads like AFR. I have two sets of covers that still neither fit exactly perfect and seems like they are not wide enough.
I had to go with doubled up gaskets to raise the cover so the edge lip doesnt have any interference with the head. FYI
I had to go with doubled up gaskets to raise the cover so the edge lip doesnt have any interference with the head. FYI