Hello all,
In the latest issue of the Europa newsletter there is a letter by Tony
Wakefield addressing a problem he had with deterioration of the fuel
lines, allowing fuel to seep through the hoses. In the letter he states
that auto fuel was used in the aircraft during testing phases and that
since then exclusively 100LL has been used. He did not mention whether
or not the fuel system might have been left dry for a period after fuel
was first introduced.
I have had trouble with various rubber fuel hoses in automotive
applications as well as with rubber fuel bladders in aircraft wings. If
they have had fuel in them for some time and are then left to dry out
they will become brittle and form small cracks. The way this has been
explained to me is that the fuel solvents leach certain constituents out
of the rubber polymer. While the fuel remains present the molecules of
the fuel itself take the place of the missing elements and keep the
rubber supple and usable. But if the fuel is then allowed to dry out of
the rubber serious deterioration takes place. The small cracks may not
be readily evident on hoses with cloth braid on the outside.
I hope this info is helpful to those on this list.
I have been assisting in the construction of XS Kit No. A121 and we have
gotten several very useful tips from this forum. Thank you all.
Kevin Hickey
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