A high EGT would imply a lean mixture to me. The fact that an additional
pump had a degree of improvement, then cleaning the filters made a
significant difference, would suggest to me that you're not getting
sufficient fuel pressure due to blocked filters.
(I emphasise that this would just be my first theory, and other causes
shouldnt be ruled out!)
I'd check your filters again, would take the old one you took out apart and
check it, would drain the tank (through a filter, checking what you get, and
making sure the tank is well agitated during the process by some means), and
would give the tank a good flush.
One thought, when you refuelled before the flight, was it direct or through
a filter funnel?
Regards,
Jeremy
Jeremy Davey
Europa Monowheel 537M G-EZZA
Europa Club Vice-Chairman, Webmaster, PFA NC Representative
PFA EC Member
If you can keep your head when all about you are losing theirs, then it is
possible you haven't grasped the severity of the situation.
Tail done
Standard XS wings with mods underway
CM installed in fuse (with airbrakes fittings)
1400 build hours to date
Intended fit:
Rotax 914 turbo, Airmaster CS fully-feathering prop
Lots of lights, buttons, switches, gizmos, and alarms
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Matthew
Carpenter
Subject: Europa-List: Rotax 914 problem/question
A weird problem with our 914 showed up on the way home from Oshkosh last
Wednesday.
1.5 hours from Oshkosh heading to Texas, the altitude was 6500 msl and
the OAT was 44F.
The engine begin to lose power, the sound changed. The EGT, normally at
1360 was at 1550 and going up.
When the EGT hit 1600 the engine begin to sound ruff, like it was
starting to miss, but not to the point of stopping.
To us it seemed the the mixture was to lean.. might we be seeing some
carb ice? Water in the gas?
I turned on the secondary full pump, the EGT dropped down to 1550, and
the engine did smooth out, but the power was
still not there. The MP showed 31, RMP was at 5000, it all looked
good.. except for the EGT.
We landed and replaced the full filter.. maybe it was starting to clog up..
Ran fine for 1 more hour, 4500msl and 65F OAT, then the problem came
back. I went down to 2000 msl, and the problem went
away.
We landed once more, and I checked all the hoses, and electrical wiring
under the hood, everything looked fine.
We ended up flying the rest of the way at 3500msl, and had no problems
for 3 hours..
Any ideas?? Why would the EGT drop when I turn on both fuel pumps, and
then return to 1600+ with only 1 pump on. (even toggled the two pumps).
Hope someone had some ideas, I would like to fix it before the next long
flight.
Thanks,
Matt Carpenter
A138
N138WJ
Amarillo Texas
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