I had a bad ignition module which showed up as a very low rpm on the mag
check. It was almost 900 rpm difference. Turns out it was the top module
which fires the top plugs on the 914. I went thru the Ignition
troubleshooting guide (see attached) it pointed me in the right direction.
It was not firing the top front two plugs. I could pull the plug wires off
and no difference. It was amazing how well the engine ran with just the back
two top plugs working when I was testing just the top module. The engine
kept running with just one plug firing on one cylinder as I was testing and
pulling plug wires off.
The engine has under 500 hours and I cannot get any explanation from any
Rotax people as to the cause of failure. They only say that failures are
rare, and I might add expensive $950. All is fixed and I had a great flight
today to a few of the Islands up here in the Pacific Northwest (looked for
Fred on Orcas, didn't see him:)
Jerry Rehn
Europa XS Mono 914
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