The second engine was purchased in November 1990 and came with
a 90 days warranty. As soon as I got it installed in the plane
and running, I noticed that the sound from the exhaust at idle
was different from the first engine. Using a modified
compression tester, I finally determined that one of the
compression chambers of number one rotor was leaking
compression. The seller assured me that it was a temporary
condition, due to a period of a few months of cold storage and
would cure itself shortly. I could not convince him to honor his
warranty and I could not convince myself to call in a lawyer. I
felt that it would end up being too costly.  

I tested the engine
at power. Static rpm was less at 4650 rpm, but the engine
started easily, it accelerated well, ran smoothly at full power
and was capable of take-off power and speed. At first, I flew it
in the circuit only and found out that at wide open throttle, it
would reach 6000 rpm at 1500 feet and seemed to be as powerful
at full power and high rpm as the first engine.  

On 22 March
1992, at 82 hours 42 minutes airtime, while about one hour into
a cross-country flight, I landed at an enroute airport for an
unscheduled short duration stop. I took off again shortly and by
the end of the airport grounds, the engine faltered and lost
power and rpm. A quick glance at the gages showed the oil
pressure pegged at maximum of 100 psi. After a few seconds, the
engine resumed normal output and I turned hard left for an
immediate landing. On downwind and final, the oil pressure
showed back to normal. Once on the ground, I noticed drops of
liquid on the canopy that looked like engine oil.

An immediate examination showed two things. Engine oil was
leaking in quantity out of the engine block from behind the
flywheel and also a small quantity of whitish goo had leaked
from the two small hose fittings located on the intermediate
housing on the base of the engine oil filler tube. I had
connected clear plastic tubes to these fittings, because they
were dropping small quantities of whitish goo on the engine and
the tubes deposited the goo outside the cowling, keeping the
engine cleaner.

I suppose a combination of below freezing temperature and high
relative humidity caused the tubes to ice up in flight and plug
up the fittings, causing an increase of the internal pressure in
the engine crankcase and oil pan, until the rear oil seal blew
out.  I removed the propeller, cowling, the propeller speed
reduction unit (PSRU) and the flywheel and confirmed that the
rear oil seal had blown out. With a new rear oil seal, the
engine ran normally, showing normal oil pressure. Still, repairs
completed, I needed a few days to work up the courage to
take-off again and fly home.  I still use clear plastic tubes
connected to the small hose fittings located on the intermediate
housing on the base of the engine oil filler tube, but I keep
them tied close to the engine and oil pipes so that they will
not freeze and plug up. In addition, I do not use clamps on the
fittings, so the tubes can slip off easily from the fittings if
the pressure builds up inside the engine for any reason.

>From 13 January 1991 to 12 September l992, I flew that engine 93
hours. However, of course, it never cured itself of that leaky
compression chamber. Never the less, it started easily and ran
smoothly at full power. I flew it to 10,000 feet several times
and once to 11,200 feet. Finally, on 12 September l992, it
failed somewhat like the first engine. During the take-off run
this time, just before lift-off, the sharp explosion and the
very unbalanced shake and wobble. I removed it from the plane
and bought the present third engine. I still do not know what
caused the second engine to fail, since I did not disassemble it
to try to find the cause of its failure.  Why did I fly that
engine, knowing that it was flawed? I do not try to justify it.
However, consider this:

 The engine started easily and ran smoothly.
 It produced good power at W.O.T.
 The oil pressure and temperature were normal at all rpm regimes.
 The oil consumption was normal for an engine equipped with the
  oil-metering pump.

At that time (1992), I still believed that the Rotary was too
complicated for unspecialized amateurs like me to inspect,
repair and overhaul. In addition, I very much wanted to believe
what the seller was telling me about the engine curing itself.
In retrospect, I certainly would not fly it today but would
disassemble it and correct the flaw before attempting to fly it.
Of course, I am a few years older by now."

Yvon Cournoyer

 
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