I have been watching with interest the exchanges on the Forum about fuel smells.
My Europa exhibits this problem during and immediately after take-off, but only
---From time to time.
On 6th October I flew my aircraft - twice - for the first time for six weeks.
Absences
abroad and in UK, and a 50 hr check, were responsible for the long pause.
After I had completed the engine run at the end of the 50 hr check, there were
10 litres of Avgas in the main tank, according to my Avalec.
On 6th, before my 1st flight, I uplifted 30 litres and got airborne about 10
minutes
later. There was a very strong smell of fuel as I climbed away, which persisted
for 5 minutes or so until the cockpit air had been changed by the NACA
scoop. The second flight that day was 4 hrs after landing from the first, and
there was no smell.
Today, in an attempt to isolate the cause of this problem, I carried out the
following
sequence.
I flew for 15 minutes, with a start fuel level of 26 litres. There was no fuel
smell before, during or after take-off.
Before the second flight, I wrapped and sealed polythene around the rubber pipe
part of the fuel filler (I have the baggage bay extension); this seal included
the breather pipe and the fuel sight gauge pipe. 15 litres of fuel were then
added; during the refuelling I kept my nose close to the area of the tank top
through which the Avalec is fitted. There was no smell of fuel during
refuelling,
and when I then took off with 38 litres recorded, there was no smell of fuel
at any time during the 10 minute flight.
I had fitted the seal around the rubber pipe part of the tank filler because
there
have been some messages on the forum suggesting that there might be some
porosity
in the rubber pipe.
After the second flight, I removed the polythene seal, and then added another 15
litres. Again, there was no smell at the tank-top during refuelling, and no
smell during the flight, which started with 52 litres in the main tank.
I am mystified by the results of this simple trial, when compared with the first
flight on 6th..
I am now wondering whether there is an imperfect seal at the tank-top Avalec
plate,
which might have been aggravated on 6th October by a refueller who filled
the aircraft up much faster than today's duty refueller, who is always very
careful.
I should point out that I have made a fibreglass cover which fits over
the tank top to prevent damage to the Avalec probe.
Who has any other suggestions about this fuel smell problem? Are those of you
who
suffer badly using the Avalec probe, or a similar probe fitted through the
tank top?
There has been so much about this problem on the forum that it would be nice to
try to isolate the problem once and for all.
Best wishes to you all,
David
UK 265 G-BZAM
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