As an aside IO540... our Aztec engines run hot. With the Piper oil temp
probe located just after the cooler and the JPI probe located ahead of the
#1 cylinder, the Piper oil temp rarely hit 200 but the JPI's will show 230
and if we climb out too steeply they'll bust the 235 alarm. I changed the
oil and filters in ours last night and noted about 1/2 dozen carbon
particles in the sump screens of each engine with a few small chunks in the
filters. 66 hours on filter changes. Oil had 33 hours on it and was brown,
definitely not black.
Jim

"Dan Luke" wrote in message
...

"Jim Burns" wrote:

From Sac Sky Ranch:
1. Blowby of combustion gases past the piston ring belt. Accompanied by
high
oil temperature and increased oil flow out engine breather. Check engine
compression.

Borescopes and compressions were ok, but I still think it was something
like
this that was going undetected. But what?


oil temperatures. (any carbon deposits in the screen or
filter?)

Oil temp. was monitored on the JPI engine analyzer with a high alarm
setting
of 215 deg. F. Never had an alarm.



3. Contamination of oil.

That's what my regular mechanic said.

--
Dan
T-182T at BFM