As I understand it, the Andair filters have a 75 micron (metric) screen.
Rotax recommend nothing coarser than 100 micron. So maybe the Andair screen
is not too small.
In any case, the Europa bleed return orifice is 75 micron, so a coarser
filter would risk passing debris that could block this restrictor.
Duncan McF
----- Original Message -----
From: "Geoff Leedham" <geoff@gleedham.freeserve.co.uk>
Subject: Re: Europa-List: Fuel Systems
<geoff@gleedham.freeserve.co.uk>
>
>
> > >This should also cover the situation Europa once described where their
> > >914 started coughing, but recovered when pump 2 was switched on, and
they
> > >subsequently
> > >found the Gascolator filter heavily gunged
> >
> > It should be noted that this was not an Andair gascolator, it was of a
> > design almost guaranteed to bung up with any contamination. Andair
> describe
> > a test they did to demonstrate this. Because the brass screen is close
to
> > the outlet hole, significant contamination cause deflection of the
screen
> > which then can contact the edge of the outlet, you then have the small
> > outlet hole covered with contaminated screen.
> > The screen of the Andair is well displaced from the outlet and placed
> where
> > the fuel is moving slowly, (large area).
> > Graham
>
> Graham, although the Andair filter is well constructed I still had a
problem
> at the beginning of this year with an almost complete blockage. I had
added
> fuel from a couple of 10 litre metal fuel cans that I have used for the
last
> few years. Went flying for an hour, landed and decided to do a run up just
> to check the prop setting. At that moment the low fuel pressure lamp on
tne
> EIS lit and a few seconds later the engine died.
> Took the Andair filter apart and found the filter screen completely
> obstructed with a fine dust like powder which turned out to be powdered
rust
> from the fuel cans.
> I always filter the fuel I add through a Mr Funnel water seperator funnel
> which has a fairly fine filter built in, however this powdered rust had
gone
> through it.
> It was fortunate that this happened on the ground and that I carried out
> the power check after landing.
> I feel that the Andair filter is possibly too fine as I'm sure this dust
> would have easily passed through the carb jets without a problem.
> Needless to say, the fuel cans have gone!!
>
> Geoff Leedham G_EOFS
>
>
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