Tom, Jim, et Listers,
I have heard various theories about using, or not using, valve stem seals.
All the way from using the really good Teflon seals to using no seals at
all, the latter choice being made to promote good lubrication of the valve
stems. I started out years ago using Teflon seals, the ones that require
special machining to install, and have had good results, so I've stuck with
'em. However, if you have a good tight stem-to-guide fit, then I would not
expect there to be a great deal of oil getting into the combustion chamber;
at least not nearly what Jim is having. If the guides were that loose, then
the heads will soon need to be reworked anyway, stem seal or no stem seal.
I'm still betting the PCV valve is the problem.
Bob
At 06:25 PM 5/16/99 -0700, Tom Hall wrote:
>At 05:59 PM 5/17/99 -0400, you wrote:
>
>Best non-destructive tool for this application is a leak-down tester which
>will measure the relative leak rate for each cylinder at TDC. Similar to a
>compression test except that it is a static test and not a dynamic test. A
>liberal squirt of oil in a low cylinder followed by a retest will improve
>(reduce) the leak rate if it is ring related, and have essentially no
>effect if it is valve seal related. The test should give you uniform
>readings on each cylinder in the 85% or better range. If the number are
>below this level, mechanical work is likely warranted.
>
>You might also pull the valve cover on the offending side and inspect for
>valve seal components which would indicate failures that are obvious.
>
>Tom
Robert L. Palmer
Dept. of AMES, Univ. of Calif., San Diego
rpalmer@ames.ucsd.edu
rpalmer@cts.com
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