Help with leaking valve cover??? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**68350** · 02-23-2007, 02:01 PM

I have a set of cast aluminum valve covers and the passenger one leaks. I have tried fel-pro gaskets, rubber gaskets, and even silicone, and it still leaks. I have a high volume oil pump, which puts the small block at 60+ psi for driving. Could the valve cover be bad, or is the oil pressure to high? thanks

70rs/ss · 02-23-2007, 02:06 PM

Quote:

Originally Posted by 68350

I have a set of cast aluminum valve covers and the passenger one leaks. I have tried fel-pro gaskets, rubber gaskets, and even silicone, and it still leaks. I have a high volume oil pump, which puts the small block at 60+ psi for driving. Could the valve cover be bad, or is the oil pressure to high? thanks

Cast aluminum should not leak, are the gaskets split? If not then that's not the leak. Sounds like maybe blowby? It the top of the valve cover wet, do you have a breather, with a PCV or just breathers? These are all part of the equation. Lastly, is the cover split, cracked or broken? If none of the above look at the breather system. Oh crap how about baffles? Are the covers baffled, if not it is a straight shot out of the cover.

hvychve · 02-23-2007, 02:20 PM

[QUOTE=70rs/ss;2044701]Cast Lastly, is the cover split, cracked or broken?
I would have to agree with above, If you had tried a new gasket and even went as far as to silicone it. I think I would be looking for a crack, too much oil pressure would only be an issue where there are pressure points, valve cover area is not one ... pull your v/c off again(keeping in mind location where oil was coming from) and look real closely for a crack, v/c may just be junk from someone over tightening it.... goood luck

cdowns · 02-23-2007, 02:24 PM

inop pcv system is good for valve cover leaks

fastwillie 696969 · 02-23-2007, 03:36 PM

check with a straight edge see if any defect in the casting i had a m/t valve cover that had a little bump barely see it with your eye i changed the cover and wah la no leaks

724x4a/cchevy · 02-23-2007, 05:06 PM

Have you tried the steel core valve cover gaskets? I havent tried them yet. Just a thought.

1968SWBBigBlock · 02-23-2007, 05:28 PM

Make sure the rail that the valve cover sits on is not cracked, ie the top of the head. Try the steel reinforced VC gaskets if you have not. Also before you use your form a gasket or regular gasket, clean the top of the head and the valve cover with brake cleaner. That insures a good clean surface sealing surface.

Aarons72s · 02-23-2007, 07:46 PM

One last thing. On the motor out of my orange and white, the valve covers always leaked. When I pulled the the motor apart I found that ther was still some casting flash on top of the heads keeping them from sealing.

**68350** · 02-23-2007, 07:49 PM

I think the valve cover might be bad, since the motor was professionally rebuilt. I will try a new set of covers and see what happens. thanks

02-23-2007, 02:01 PM	#1
68350 Senior Member Join Date: Jan 2002 Location: Williston, ND Posts: 2,999	Help with leaking valve cover??? I have a set of cast aluminum valve covers and the passenger one leaks. I have tried fel-pro gaskets, rubber gaskets, and even silicone, and it still leaks. I have a high volume oil pump, which puts the small block at 60+ psi for driving. Could the valve cover be bad, or is the oil pressure to high? thanks __________________ 68 Chevy CST/10, 50th Anniversary, 327/th400, 373 posi, buckets 68 GMC Shortbox Stepside, 402/th400, Tilt, Tach, Bucket Seats, 3.08 Positraction 69 Chevy Camaro SS, 383, 4 speed, positraction 70 Chevy El Camino SS396, Triple Black, 454/th400, Tach 70 Chevy Shortbox Stepside 4x4, 350/th350, Tilt, Tach, Cab Lights, Bumper Guards, Tow Hooks 70 Chevy 3/4 Longbox, 350/auto, 70k, SURVIVOR 71 Chevy Blazer, CST, 350/auto 71 GMC Sierra K2500, 454, 4 speed, 4.10 posi, 37s 71 Custom/30, Open Road, 350/th400, tilt 72 Chevy Shortbox Fleetside, 496 Stroker/th400, Tilt, Tach, Bucket Seats, 3.42 Posi 72 GMC Sierra Grande 2500. 427/th400, tilt, a/c, tool and stowage, buckets/console, 3.54 posi

02-23-2007, 02:20 PM	#3
hvychve To The Levy Join Date: Jan 2007 Location: california Posts: 391	Re: Help with leaking valve cover??? [QUOTE=70rs/ss;2044701]Cast Lastly, is the cover split, cracked or broken? I would have to agree with above, If you had tried a new gasket and even went as far as to silicone it. I think I would be looking for a crack, too much oil pressure would only be an issue where there are pressure points, valve cover area is not one ... pull your v/c off again(keeping in mind location where oil was coming from) and look real closely for a crack, v/c may just be junk from someone over tightening it.... goood luck

02-23-2007, 02:24 PM	#4
cdowns Senior Member Join Date: Jan 2003 Location: daytonabeach Posts: 22,956	Re: Help with leaking valve cover??? inop pcv system is good for valve cover leaks __________________ 71c-10 350/2004r/4:11 lowered3/4 longbed/dead by hurricane MEANING OF DEATH::::: SOMEBODY ELSE GETS YOUR STUFF DONT BELIEVE EVERYTHING YOU THINK TAKE MY ADVISE;I DON'T USE IT ANYWAY

02-23-2007, 03:36 PM	#5
fastwillie 696969 ~Rest In Peace~ Join Date: May 2005 Location: CALIFORNIA NOR CAL Posts: 9,707	Re: Help with leaking valve cover??? check with a straight edge see if any defect in the casting i had a m/t valve cover that had a little bump barely see it with your eye i changed the cover and wah la no leaks __________________ is it fast ? it has a lighting bolt donut? B___H please, I can remove 90% of your so called "beauty" with a kleenex

02-23-2007, 05:06 PM	#6
724x4a/cchevy Self-proclaimed LED man Join Date: Nov 2003 Location: Harrisburg, Missouri Posts: 1,021	Re: Help with leaking valve cover??? Have you tried the steel core valve cover gaskets? I havent tried them yet. Just a thought. __________________ My LED Website My Photobucket Album of LED's Ask me about hand-made custom L.E.D brake and reverse lights. <- LINK I also do LED: -Third Brake/Cargo -Brake (truck and burb) -Reverse (truck and burb) -67-68 Front Turn Signals -69-70 Front Turn Signals -71-72 Front Turn Signals -GMC Front Turn Signals I can also do custom lights for other vehicles....i did a set for a AMC Gremlin once Norwood Survivor

02-23-2007, 05:28 PM	#7
1968SWBBigBlock Active Member Join Date: Oct 2006 Location: Ohio Posts: 1,643	Re: Help with leaking valve cover??? Make sure the rail that the valve cover sits on is not cracked, ie the top of the head. Try the steel reinforced VC gaskets if you have not. Also before you use your form a gasket or regular gasket, clean the top of the head and the valve cover with brake cleaner. That insures a good clean surface sealing surface. __________________ 1968 SWB 454 + .040, 490HP x 540 FT pounds of Torque 10-1 Kb Forged pistons, recon rods w/ ARP wave loc bolts 781 heads Ported with 2.19/1.88 SSTvalves Lunati 60204 cam, Micro Trol lifters, Ported Edelbrock Performer Rpm manifold armor coated, Pertronix Triple Strike Ignition Holley 770 Street Avenger carb,Headers armor coated Built by Watson Ruppel Performance in Sarahsville Ohio. Hardshift Tranny Built Turbo 350,TSI 10" 3000 stall 12 Bolt Eaton Posi 4.10 Richmond Gears moser axles 18.5" x 31" Hoosier Pro Street Radials ET Classic 5 Wheels - polished Power Steering, Power Brakes,Disc Brakes,Tach & Gauge Dash, Tilt,Factory Air (gone) Custom Paint & Body Work Special thanks to my wife, my son and my money tree

02-23-2007, 07:46 PM	#8
Aarons72s Registered User Join Date: Apr 2006 Location: oklahoma Posts: 10,669	Re: Help with leaking valve cover??? One last thing. On the motor out of my orange and white, the valve covers always leaked. When I pulled the the motor apart I found that ther was still some casting flash on top of the heads keeping them from sealing.

02-23-2007, 07:49 PM	#9
68350 Senior Member Join Date: Jan 2002 Location: Williston, ND Posts: 2,999	Re: Help with leaking valve cover??? I think the valve cover might be bad, since the motor was professionally rebuilt. I will try a new set of covers and see what happens. thanks __________________ 68 Chevy CST/10, 50th Anniversary, 327/th400, 373 posi, buckets 68 GMC Shortbox Stepside, 402/th400, Tilt, Tach, Bucket Seats, 3.08 Positraction 69 Chevy Camaro SS, 383, 4 speed, positraction 70 Chevy El Camino SS396, Triple Black, 454/th400, Tach 70 Chevy Shortbox Stepside 4x4, 350/th350, Tilt, Tach, Cab Lights, Bumper Guards, Tow Hooks 70 Chevy 3/4 Longbox, 350/auto, 70k, SURVIVOR 71 Chevy Blazer, CST, 350/auto 71 GMC Sierra K2500, 454, 4 speed, 4.10 posi, 37s 71 Custom/30, Open Road, 350/th400, tilt 72 Chevy Shortbox Fleetside, 496 Stroker/th400, Tilt, Tach, Bucket Seats, 3.42 Posi 72 GMC Sierra Grande 2500. 427/th400, tilt, a/c, tool and stowage, buckets/console, 3.54 posi

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