Richard,
I don't know if my emails get beyond my computer, but here goes:
Ignition could be the problem. It takes higher voltage to arc across
higher pressure fuel mix.
If the ignition coil or distributor cap or rotor or wires have
conductive "dirt" on them, the spark may jump along the short circuit
rather than through the spark plug.
In a borderline situation, a higher throttle setting increases the
combustion pressure enough to force the voltage to a higher level before
arcing, and the higher voltage causes the current to take a short
circuit across the deteriorated surface of the distributor cap, etc.
Reducing the throttle reduces the plug gap voltage required, and the
engine runs normally.
Now why this should occur 1 1/2 hrs into cruise, or at higher altitudes,
I can not guess. Heat distribution?
Your troubleshooting has eliminated the likelyhood of it being a pump or
plug problem.
I have no experience with the Rotax, but in a different engine, I'd
replace the distributor cap and rotor.
Donald Ingram
xs mono
----- Original Message -----
From: Richard Schultz
To: europa-list@matronics.com
Sent: Wednesday, August 02, 2006 9:54 PM
Subject: Europa-List: Oshkosh by air - return by Avis
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