Scotty,
IMHO, your low compression readings show that the rings have
not seated properly. I have always heard that you check compression
before and after adding oil to the cylinders so that you can tell the
difference between poorly seating valves (no increase in
compression), and a poor seal for rings (increase in compression as
the oil temporarily prevents leakage at the cylinder walls). Since
you have just completed a major overhaul, my humble guess is that the
controlled wear necessary to allow sliding surfaces to work together
with the proper microclearances has not taken place. In the bad old
days, a "break-in" period was always required to accomplish that
task. In fact I owned a car once which NEVER "broke in" properly.
With engineering advances made in the last 20 years we don't
normally think much about this process, and there is normally very
little an owner has to do to assure good service beyond the usual
maintenance and lubrication a modern car requires.
I will probably be flamed for this, but it seems to me a
small amount of CONTROLLED wear is called for, and that again IMHO
will take place if you substitute straight SAE 30 oil for your
multi-viscosity oil for about 1,000 miles. Then recheck the
compression; my guess is that the readings will be uniformly high.
Anyone else want to jump in on this? I don't want to be held
responsible for a siezed engine! The usual disclaimers ---
Lew (what the hell do I know?) Dove
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