Posted for "Matt Hapgood" <hapgoodm94@alum.darden.edu>:

Sorry, not tappets, but lifter bodies.  And they were reground...

Matt

  -----Original Message-----
 
  I had a prop strike at Chapel Hill, NC airport about 4 weeks ago.  It was
real bummer - happened while I was taxiing in the grass.  Some of you
probably remember - it started a hot debate.

  Anyway, here's the update.

  I removed the AeroComposites prop and had it sent to American Propeller in
California for blade replacement.  The prop shop that dismantled the hub and
blades forgot to ship the stuff... for almost three weeks.  Everyone
involved knew I wanted this work done quickly so I could get back in the
air.  Not until I called to see if they had the prop back did I get the "Uh,
yea, I think it's here".  To which I responded "Great, I'll come pick it
up".  To thich they responded "Uh, let me call you back on that".  Long
story short, it was sitting in the corner and no-one bothered to let me
know.  So NOW it should be back here in a week or two.

  But that's largely irrelevent, because the engine almost certainly won't
be ready in two weeks.  No problems from the prop strike, but it was a sick
puppy.  One cam lobe, for the #3 and #4 intake, was worn almost round.  It's
close to 1/4" shorter than the rest of the lobes.  I'll shoot a picture in a
day or two and post it.  Metal has embedded in the piston walls.  Cylinders
are too close to minimums to be rehoned.  Oil pump housing is scored.  Shop
suspects the cam damage was caused by the tappets (?) which were remans and
not new.  All the rest of them looked great, but those two looked like the
top of an apple pie.  Ugly.  And this engine supposedly only has 400 hours
on it.  Maybe it was the 3 year storage period.  Who knows.  I bought the
engine used.

  My wallet will be hurting, but it will be nice to know that will all be in
good shape in a few weeks.  I never was really comfortable with not knowing
(or trusting) the full history of the engine.

  So I guess I'm glad I tore it down.  But I'll be down for awhile longer.

  Question - the engine, stock, has 8.7:1 pistons.  At the recommendation of
some I am considering 9.5:1 pistons for replacement.  What are the pros and
cons?  I have electronic ignition and can vary the timing.  Thus far, the
engine has been running VERY cool (about 300 on CHTs in cruise).  Maybe
those rear cylinders will get a little hotter with a full intake stroke?

  Happy flying, and I appreciate everyones input.

  Matt