valve stem seals ?
Thread Starter
Race Director
Joined: Apr 2006
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From: I'm not doing as well as I expected, but I never expected I would
valve stem seals ?
Got a 65 L79, does it use both the umbrella type and o-ring seals? Did searches but could not find anything definitive.
Drifting
Joined: Jan 2013
Posts: 1,772
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From: Asheville NC
I seem to remember that the oring type were original on both and sometime along the way the umbrella was added to the intake.
I put both types of seals (felpro) on the exhaust and intake but that's just me.
Im sure others will chime in.
Phil
I put both types of seals (felpro) on the exhaust and intake but that's just me.
Im sure others will chime in.
Phil
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From: Corsicana, Tx
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Only O ring from factory...but you can do much better with a true seal that stays on the guide itself. Viton's etc.
JIM
JIM
Safety Car
Joined: Oct 2016
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From: Olive branch Ms
A few things to pay attention to. 1. If you are going to use the umbrella type there are different styles. Make sure the diameter is small enough that the spring doesn't rub it and watch for the thickness at the top. The thin ones are not very good but the thick ones can be thick enough that the retainer smashes them against the guide especially if you have much lift. 2. You can't just put a positive seal on as the guides are not concentric i.d. to o.d. Later in the 80s Chevrolet started machining the guides for positive seals and used both positive and oring for a while.
Thread Starter
Race Director
Joined: Apr 2006
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From: I'm not doing as well as I expected, but I never expected I would
Went with the umbrellas and O-rings which fit very well. the valves had the positive guides on them which looked in good shape, but no O-ring, but as Robert said, I doubt the guides were machined. Now for the " Oh crap" moment, I was down to the last two cylinders and noticed I was going to have one set left over. I was pretty tired, so now I gotta backtrack, and get another set of O-rings as well.
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I wrote an article on valve seal replacement on SB Chevy and one of my first instructions is to count the o-rings and umbrellas before you start.
If you want a copy send me you email address.
Joe
If you want a copy send me you email address.
Joe