We were flying 'XDY at the end of last week when suddenly the oil pressure
dropped from its normal 50-53 lbs down to 22 lbs. I immediately cut the
throttle. We were alrteady in contact with our destination airfield,
although we had not found it at this stage (it was new to us). I put out a
call requesting in a straight in approach with an oil problem (and at the
same time found the field). I manage to glide it straight down to the
numbers and once over in the parking lot removed the cowlings to discover
the problem.
The oil return pipe under the Rotax 912, where it is very close to the
silencer had become very brittle and fractured. We had in fact heard about
this brittleness from another flyer back in February, athough the indication
was that it was more of a problem on VP prop equiped engines due to the
higher revs on take-off. As a result of the conversation we had fitted
firesleeve to the pipe in the area, but obviously even this had not
protected it.
Discussion with the factory has indicated that they knew about this
brittleness problem on some aircraft, but as it had not developed further
than that, had not put any time into the problem. A mod now seems
appropriate and in the meantime Skydrive, the Rotax agents, have said that
they are going to contact Europa to suggest a 50/100 check of the pipe in
the area of the silencer.
A check of our engine is now being completed and we should get it back
Tuesday for reinstallation and testing. The hope is at this stage that we
will not have to pay out for a major overhaul or a new engine as I shut it
down straight away and it appears that oil was going round all the time,
although the pressure was fluctuating, going as low as 5 lbs, but normally
around 15 - 20 lbs.
Anybody flying with a Rotax would best be advised to check their pipe as
best they can now. We have done just over 150 hours on ours to give you some
idea of its use.
Bob Fairall, who was flying his Europa with me when I had the above problem,
has since looked at his installation and seen some scorching of the
firesleeve. However we think he has come up with a solution. He has reversed
the banjo fitting on the bottom of the engine so that it faces rearwards.
This means that the rubber oil pipe goes into an ever increasing gap
(instead of a reducing one) as it passes to the rear of the engine, then up
the back and over the top to the oil tank. He is going to run the idea past
Europa tomorrow and we will let you know the outcome.
Dave Watts 'XDY
|