Piners,
This is kinda techie, so delete now if you dont want gory details
about valvetrain stuff.
I was pulling my head last night on the alpine, when I ran across some
interesting
details on my engine.
The headgasket was suspected of failing after a very spirited driving
session
where the engine was subjected to several seconds of 7500+ rpm opperation.
BTW, this engine was NOT built for those kind of revs, as others I have
built were.
The engine sat dormant for over a year, until I could get a ROUND TOIT.
Pullinf the rocker gear last night I discovered that a single rocker finger
had really taken a pounding to the valve stem. I continued on.
I pulled the side plate and then started pulling pushrods and lifters.
As I inspected number 2 intake pushrod, I found the lifter was full of oil.
Funny the other lifters dont seem full of oil...
I pulled the lifter clear out and found that it lacked the drain hole in the
bottom of the lifter, and it wouldnt drain the oil. I suspect that the
added
mass of the oil in the lifter caused valve float, which allowed the rocker
to beat on the stem.
BTW, the lash was correct, and the engine has about 40 hours of running
time including two speed events/races.
I dont recall where I got these lifters from, might have been Vicky Brit,
or might have been Sunbeam Specialties, I do recall having to return
lifters back to S.S. for having chips in the sides, but I dont know if these
were the replacements or not.
Secondly....
I discovered that the rocker fingers that I paid $5 each to have them re
profiled
were still very coarse, and had not really worked into the stems smoothly.
I recall that when I had the fingers done, they looked to me to have been
done on a belt sander, and not on a quality ginding jig as they were
reported
to have been.
This explains my perpertually changing valve lash that was experienced
in years past for those that recall that e-mail thread.
In conclusion:
1) Verify your lifters if you have them out.
If the lifters lack the oild drain passage, gunk and metal particles
get in, and cant get out, whicg causes rapid wear.
2) If you have your rocker fingers re profiled, be sure that the finish is
fine
and dont take the machinists word that it will be OK, becuase he doesnt
care one way or the other.
Jarrid Gross
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