|April 27th, 2008||Flight Hours: .9||Total Hours: 7.1|
|After the success of the
last couple flights and the ability of the aircraft to sustain
appropriate engine parameters, I decided it was time to really start
testing the airframe.
I set out for a cross-country flight to Scappoose, OR (SPB) and back. This took me approximately 36nm from MMV.
The landing at SPB gave me my first hick-up. With the TPS set "properly" the idle would hunt below 2500 rpm. This was a bit disconcerting at low altitude (50') (I thought this wouldn't happen if I removed the idle air control valve from the intake but left it plugged into the computer). But, I found it quickly manageable by decreasing prop pitch and increasing rpm to 2800.
I love having the controls on the stick. Everything is instantly available for these situations.
Upon returning to MMV I kept the idle-hunt situation in mind and didn't let the engine rpm drop below 2600 rpm. The hunt didn't happen and the mis-fire codes did not reproduce as the would each time I reduced power in the passed.
Maybe 2600rpm is the magic number?
|Upon landing I found that a
small amount of gearbox oil had run down the belly of the plane.
Idle hunt (surge) at low rpm, below 2500 upon power reduction.
Mis-fire check-engine light flashes when power reduced at altitude below 2500 rpm.
|I cleaned the oil off and
removed 1.5ozs from the overflow to attempt to keep this from happening
This reduced the total gear oil to 18.5oz.
I decided to run a short hose out the cowl and point it forward to see if this stops the outflow of oil from the gearbox.
Both the idle hunt and mis-fire triggers seem to be reduced by keeping rpm up and adjusting the prop to slow the plane down. Will continue to carefully monitor.
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