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Old 07-09-2012, 08:08 AM
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Hey cobalt,
Quote:
Originally Posted by cobalt327 View Post
That is a positive type seal, although the valve stems are set up w/the same double grooves (one for the keepers, the other lower groove for the small O-ring type seal) and there is a tin oil deflector, like has has been used since day one, pretty much.
I wanted to run something by. You mentioned that the picture of the valve I posted in post #136 has double grooves. I've taken a look a few times at the images I have as well as the valve stems themselves, but I am only seeing one groove for the keepers, much like the one shown on the right in this image (second one) from another forum by one of our members here: "2 groove valves: post #5. There is another view of both the intake and the exhaust stems in post #139.




Quote:
Originally Posted by cobalt327 View Post
The second ones have a more positive sealing area, and might be the better choice for used valve stems. But there can be too much sealing; you want there to be a slight amount of lubrication reaching the valve stem/guides. But in the case of a SBC, the guide is the head itself (cast iron) so there is always "extra" clearance.

Bottom line is I'd expect either to work. The second ones would be a good intake seal, the first ones possibly a better exhaust seal (where you need a bit more lubrication reaching them). If you were only going to get one set, the first ones in conjunction w/the small O-rings, or the second ones w/o O-rings.
Great! I'll consider ordering both sets. Otherwise I'll do the second set by itself. The reason I am concerned about getting the right set is because I've never replaced these before and do want to eliminate the plug-fouling issues. I definitely follow on the too much sealing, but I am not sure on how " reasonably loose" can a seal be. I imagine using a seal meant for a 0.344" valve stem is ok on a 0.341" valve stem. Any advice on this is greatly appreciated.




Hey Pugsy,
Quote:
Originally Posted by 123pugsy View Post
Hey Hawk.

You probably read it somewhere but I thought I'd throw it out there in case you haven't.

If you don't have an installation sleeve, use scotch tape around the keeper grooves to avoid cutting the seals.
Actually, one of the sets I bought from Felpro did come with a plastic sleeve. I won't be using that kit at this point, but had not come across the scotch tape method. Thanks!




Thanks!
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