big block chevy valve cover not sealing
 

bought this 1 ton chevy dually with a 1972 chevy 454. the passanger valve cover will not seal! i always use cork gaskets ( new ) ..... tried rtv silcon with it 3 different valve covers. yes they are straight and not bent. different bolts differnent hold downs. i even bought mr gasket thick cork gaskets and will not seal. i took this passanger valve cover off probably 15 plus times and does the same thing EVERYTIME anything over 2700 rpm its starts leaking. it spews out onto the header and spark plug wires. the pvc valve is on the passanger side it rattles and im getting good suction from the carb to the pvc

Do you think the oil passages on the head are clogged or something??

Maybe a return problem, try these they will NOT leak & reusable.


http://www.jegs.com/i/Fel-Pro/375/1635/10002/-1

Doubt that. Next time you have it off check the drains on both ends. One end has a round hole about 5/8" and the other end has a much larger square hole. Would be almost impossible for them to become clogged. They dump right into the lifter valley.

Permatex makes a sealer/gasket maker called The Right Stuff. You can get it at Oriellys. Warning you may never get it off again but it won't leak.
http://www.oreillyauto.com/site/c/de...2362&ppt=C1984

Really don't understand why you are having such a problem with it though. That's unusual.

Yeah I'd look a bit further into it before I went the sealer route. If you do though go right to the Chevy dealer and get a tube of gm engine sealant. Let it sit overnight and you could leave the bolts out. The stuff is like 5200 for cars!

what is your oil pressure? if its like 80 psi @ 2700 rpm's then your pushing way too much oil pressure....Btw whos valve covers and are you straightening the vc holes with a ball pean hammer b4 you install them?

i tried mercury stock stamped steel valve covers. a chrome one, and a moroso style. all with no luck. i dont have 80psi either at 2700 rpm
someone told me i need a breather on the driver side valve cover and keep my pvc on the passanger side. right now i have a oil cap on the driver side. would this help?

Are they leaking around the base? If so, use a set of the GM gaskets. They aren't cheap, but they are the absolute best gaskets made. They will last forever. I have some sets out there that are over 10 years old. Here is a link with the part #, but you should be able to get them from your local GM dealer.

http://paceperformance.com/i-6255394...r-package.html

Eddie