Valve Seals

6

62 Comet

Well-known member
My 6 doesnt puff out but certainly does when I let off the gas, I just checked out the valve seals, been a long time sonce they been changed, im doing this just cause I want to fix a v/c leak(started it up and couple days later realized and the #4 plug was bathing in oil). My question is if the seals are suppose to be flush down level with the bottom of the springs or if they're suppose to be up a little ways, b/c mine are all not all the way down to the head.

I dont know if this is clear enough, i'd appreciate any input..

Thanks, Lee
 
Lee, since the stock seals hugg the valve stem they will eventually ride up on the valve stem.
I like pc seals which have a teflon seal ring around the valve stem, but the rubber housing is held with a snap ring to the valve guide.
With the valve cover off see if the umbrella seals are still intact & have not cracked & broken because of hardening due to age.
You might want to run a compression check comparing #4 cylinder to the others. Let us know, Bill
 
If the seals ride up the stem, does it then ride up and down with the valve? If thats the case I would think some of the seals would be at lower and higher heights but mine arent like that. Ive had intentions on getting a compression tester but still havent, also i assumed but how do you guys think oil would get puddled up around the outside of the spark plug, i assumed valve cover gasket.

Any seal type suggestions? That i can get say at NAPA?
 
If the seals ride up the stem, does it then ride up and down with the valve?
Click to expand...

They could if they are still in good condition. At NAPA you should be able to get stock replacements and likely the PC type too.
 
Merccomet,
If you think about it this way, the stock umbrella seals, seal around the stem of the valve. It acts like an umbrella. Its not made to seal around the valve guide. Just shed oil away. The snug fit between the seal and the valve stem wipes the oil off the stem. If its worn so much that there's a gap between the seal and the stem, I would think that the seal will just fall down and oil will go down the guide. So, in other words, when you shut the engine off some could be up but some could be down. When the engine is running slow, the seals will grip the stem and go up and down. But anything more than an idle, the valve moves so fast that the seal cannot change direction fast enough because of inertia and it stays down more over the valve guide. Obviously it has to go down because the valve goes down but can ride up when you shut the engine off because it goes too slow.

I hope this makes sense.
 
I haven't tried the ones you posted but, what's not to like about them? I think I'll use them on my new build. But I would check them after you ran them awhile just to make sure they stay on the guide like they're supposed to.
 
You have to get area where valve stem comes up out of head machined for the positive lock style seals. I had it done on mine when they rebuilt head. The positive lock style seals are supposed to seal better and not dry out as fast as the umbrella style seals.
 
You must log in or register to reply here.
Back
Top