"pbc76049" wrote in
:

Not exactly the aircraft perspective you are looking for, BUT in recip
race motors
for sports cars, you do hot cuts if you want to read plugs or do
compression checks. This means you rev the motor to 4 or 5 grand,
stabilize it and shut off the ignition.
We find differences in the numbers we get just from excess fuel in the
cylinders with
idle cuts. Running at idle is a rich environment and the small
washdown you get can
make the numbers get funny on leakdowns.

Interesting you mention this, so we just may be able to get aviation
perspective in the next day or two.

I went to the airport this morning to see what was up with the corrosion
and found out that will be fine, but the cylinder with low compressions
isn't making the cut again after the leak test.

So, my A&P wants me to take it in the pattern, running full throttle when
I can for about 10 minutes and bring it back down for another compression
test. He is of the thinking that a high RPM will show a truer reading,
is my guess.

If the compressions don't come up, then we will have to send it off to
get it serviced.

I would have flown it today, but thunderstorms and small planes don't mix
too well, so I have to wait until this slow moving systme moves out.

Allen