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Valve cover gaskets

Holey76 - Square Nut

Holey76 - Square Nut

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Hey all, I've had a bad time with valve covers and gaskets. The center bolt style valve covers have had raised channels for the gasket. the fel pro blue rubber gasket measures .23" thick while the channel is .25" deep. They leak bad.
SO, i order VC's that have a shallow channel. But the gaskets won't sit flat in any of the VC's i have. I'll post a cpl pics. Which gaskets do you use that fit properly and don't flippin LEAK ?

20240507_123446.jpg

20240507_123440.jpg
 
Did those blue gaskets fit the stock valve cover flat ? I do not think .002 would be the cause of your leak. Check the gasket channel is not bent warped or tweaked, try to straighten it if it is. If it's bad it will need replacing. If i were doing this I would use Gasgacinch on the valve cover and the mating side of gasket, let get tacky for 30ish seconds place gasket in valve cover. tighten cover down evenly from center out.
Be sure the oil drain back holes are clear, the head surface is scraped clean and dry.
 
Wes Harden said:
Did those blue gaskets fit the stock valve cover flat ? I do not think .002 would be the cause of your leak. Check the gasket channel is not bent warped or tweaked, try to straighten it if it is. If it's bad it will need replacing. If i were doing this I would use Gasgacinch on the valve cover and the mating side of gasket, let get tacky for 30ish seconds place gasket in valve cover. tighten cover down evenly from center out.
Be sure the oil drain back holes are clear, the head surface is scraped clean and dry.
Click to expand...
.02” difference, but hey should still work

GM makes an orange one that works best
Problem is once you mess with aftermarket valve covers, you get what you get. They are not all to spec
 
duh yeah .020 still less than a 1/16". I would expect the Felpro to work. All I have ever used were GM orange myself and not very often
 
The gaskets sit on the raised edge of the head so the recess isn’t wrong. Lay a straight edge in the channel to see if the covers are bent too.
 
Wes Harden said:
Did those blue gaskets fit the stock valve cover flat ? I do not think .002 would be the cause of your leak. Check the gasket channel is not bent warped or tweaked, try to straighten it if it is. If it's bad it will need replacing. If i were doing this I would use Gasgacinch on the valve cover and the mating side of gasket, let get tacky for 30ish seconds place gasket in valve cover. tighten cover down evenly from center out.
Be sure the oil drain back holes are clear, the head surface is scraped clean and dry.
Click to expand...
These gaskets and vc's and heads are new. The old stuff was cast iron heads & steel vc w cork gaskets.
Been fighting this leak since i built the engine. Idk about the 2 thousanths inch, but it doesn't seem like that's much to compress ?

I'll try that gasket sealer, thank you.
I did add a hv oil pump but never checked the new head's drain-back hole size or quantity.
Thanks, Wes.
 
It would take a large blockage to slow the oil draining back, like a chunks of old cork gasket, or excessive rtv. If I read right you switched from perimeter to aftermarket center bolt heads. Aftermarket sometime have taller walls, possible requiring different VC bolts ?
 
Wes Harden said:
It would take a large blockage to slow the oil draining back, like a chunks of old cork gasket, or excessive rtv. If I read right you switched from perimeter to aftermarket center bolt heads. Aftermarket sometime have taller walls, possible requiring different VC bolts ?
Click to expand...
Sorry, I didn't explain that very well. The heads have the option to use either bolt style valve covers. So I have used both styles. The surface area where the gasket meets the head is milled flat unlike the rounded hump on the cast iron heads. The channel edges on the vc meets that milled surface b4 the gasket compresses.
 
Last edited:
I did take your suggestion on the gasket sealer and it does seem to be holding them down in place:woot: I've been fighting this oil leak for MONTHS, and we even had a discussion about it.
Finally found some transdapt finned vc with shallow channels to fix that part. Now, getting that gasket to sit right, should do the trick
 
Last edited:
Bent77 said:
.02” difference, but hey should still work

GM makes an orange one that works best
Problem is once you mess with aftermarket valve covers, you get what you get. They are not all to spec
Click to expand...
I've noticed that. Even Fel pro was different from one gasket to another.
eodcoduto said:
The gaskets sit on the raised edge of the head so the recess isn’t wrong. Lay a straight edge in the channel to see if the covers are bent too.
Click to expand...
These heads have no raised edge, they're milled flat. (Aftermarket aluminum)
 
Update:
I ended up buying another set of fel pro blue rubber vc gaskets, because it's all autozone or O'Reilly's had. It fit like it's supposed to. So the previous (new) gaskets were too big. Talk about an exercise in futility !! ;(
 
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