Head Valve Seals
Thread Starter
Pro
Joined: Dec 2002
Posts: 560
Likes: 1
From: Mooresville NC
Head Valve Seals
Potentially I found my overheating problem with leaking head gaskets. While I have the heads off I want to replace the valve stem seals. When I took the valve springs off I expected to see the typical umbrella seals and did not. Only a badly dried out o-ring on the bottom groove of the valve. The heads date back to a '76 smog motor - station wagon, caprice, etc. Engine is not original.
My question is, do I need only to order the O-rings or get the umbrellas or get both?
Thanks.
MILO
My question is, do I need only to order the O-rings or get the umbrellas or get both?
Thanks.
MILO
Instructor
Joined: May 2006
Posts: 168
Likes: 0
From: Florence NJ
Just umbrellas are fine, that is what I did in all mine. I got a little confussed when I saw this for the first time too. I asked a friend who owns a speed shop and using just the umbrellas was per his instructions. I had no problems, so he was right.
Le Mans Master
Joined: Sep 2003
Posts: 8,812
Likes: 2,029
From: eastern NC
Summit carries these seals... about $14.00 a set and made by TFS
http://www.amazon.com/gp/product/B00...nce&n=15684181
Regardless of who you get them from, look for a seal made of Viton®... these are some of the best seals available for this application.
Good luck... GUSTO
http://www.amazon.com/gp/product/B00...nce&n=15684181
Regardless of who you get them from, look for a seal made of Viton®... these are some of the best seals available for this application.
Good luck... GUSTO
Drifting
Joined: Nov 2003
Posts: 1,634
Likes: 4
From: Northern NJ
St. Jude Donor '04 & '05
When I did my 75's valve seals last year, here's what came out.
I replaced them with both new O rings and Vitron umbrellas too. Probably overkill, but my replacement kit included both so I figured what the heck.
Some day someone will have this engine apart and probably will be saying WTF when they find the "double protection".
BTW, it's nice not to be belching smoke at startup and upon deacceleration too. Next I have to do the same thing on the 84 as it needs them too.
Good Luck!
I replaced them with both new O rings and Vitron umbrellas too. Probably overkill, but my replacement kit included both so I figured what the heck.
Some day someone will have this engine apart and probably will be saying WTF when they find the "double protection".
BTW, it's nice not to be belching smoke at startup and upon deacceleration too. Next I have to do the same thing on the 84 as it needs them too.
Good Luck!
Race Director
Joined: Nov 2000
Posts: 11,872
Likes: 12
From: Waterloo ontario Canada
My new brodix heads came without intake seals. I wanted to install them but the local speed shop talked me out of using any seal on the intake. The exhuast have the seals in the above post.
Le Mans Master
Joined: Oct 2002
Posts: 7,098
Likes: 378
From: Las Vegas - Just stop perpetuating myths please.
Using both Pioneer umbrellas and the little stock O-rings too. No problems and have inspected them frequently but not many engine hrs yet. Some times the dampner spring eats the umbrella seals and i can't explain y. Remember the umbrella seals will ride on the vlv stem so don't try to force it down onto the guide boss.
If fact i installed the little O-rings 1st to fill the stem groove then oiled and slid the umbrella seals over the O-ring.
GM performance has the best in steet seals - PC seals made of that Viton.
norvalwilhelm, don't u means seals on the intake and no seals on the exhaust? As the intake stroke tends to pull oil into the chamber while the exh stroke has high positive press that keeps oil out until engine shutdown and oil will drip down the guide.
Good luck and please post what works MILO.
cardo0
If fact i installed the little O-rings 1st to fill the stem groove then oiled and slid the umbrella seals over the O-ring. GM performance has the best in steet seals - PC seals made of that Viton.
norvalwilhelm, don't u means seals on the intake and no seals on the exhaust? As the intake stroke tends to pull oil into the chamber while the exh stroke has high positive press that keeps oil out until engine shutdown and oil will drip down the guide.
Good luck and please post what works MILO.
cardo0
Thread Starter
Pro
Joined: Dec 2002
Posts: 560
Likes: 1
From: Mooresville NC
The heads cleaned up pretty good. Like I said in my post this is a quickie head gasket replacement to save the rest of the summer driving and some auto-x. While I was at it, I took the valves apart and removed the ice cream cone of carbon buildup on the intakes. I didn't see any visible cracks between the int/exh seats so I think I may be OK. I could see a carbon tracks from the cylinders to a couple of the water passages. The head gasket was a blue teflon type of gasket that was as slick a snot. The heads weren't even stuck to them. I'll be going to a composite gasket, only running about 8.5 in compression. The valve guides were in good condition. The outlaws are coming next weekend so I'll have plenty of time in the garage 
. I've decided to do the belt and suspenders here, umbrellas and o-rings. Thanks again, time to stir the sunday sauce.
. I've decided to do the belt and suspenders here, umbrellas and o-rings. Thanks again, time to stir the sunday sauce.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
