"Bryan.G. Wilkinsonn" wrote:
We have some queries regarding the initial parts of the fuel system
installation and would appreciate any thoughts other builders might have.
Firstly given that there is some concern regarding length of service of the
fuel hose supplied as standard, has anyone upgraded the fuel lines fitted
to
their Europa (ref. Flyer magazine and the Europa news letter) What we had
in
mind was one of the stainless steel braided lines e.g. Aeroquipe 601 OR 666
hose. Does anyone have any thoughts on fuel lines and where we might get
them? Also could anyone explain AN fittings and how they differ from those
supplied.
Secondly what is the considered opinion out there about the Andair fuel
valve over the unit supplied with the kit - it seems to be sensible to have
a unit which requires a consciously different movement to select the off
position - again any thoughts particularly from those who might have fitted
this item.
Thirdly we are considering fitting a fuel gauge in addition to the sight
tube. Again from the flyer article of Oct.99 one such unit appears to be
the
Avilec gauge. Does anyone possess further information or know where they
can be sourced?
Finally does the fitting of any of the above require PFA mod approval -
presumably the fuel gauge would, but what if we just upgrading things like
fuel lines and tap?
All information greatly received
Ian Robson kit 432
Bryan,
Good questions. I have no idea what is supplied with the Europa kit.
AN hoses use a 37 deg flare angle, which is not compatible with std
US (non-A/C) flare fittings which have 45 deg flares. As to flex line
life, it is important to repeat the NO line has an indefinite life, even
tho many sources claim that the teflon liner stainless braid line has
an indefinite life. It does have an indefinite SHELF life, but has the
same 5-10 year service life of the much less expensive 111 Stratoflex
and similar Aeroquip 303 hoses. Altho they look neat when uncovered,
I personally see no real advantage to the teflon hose over the std
rubber with internal steel braid for fuel and oil lines, esp since the
fuel lines at least should be covered with fire sleeve. Nobody gets
to see the 'cool' stainless braid in a proper installation, and the
stainless braid lines are a lot more expensive. I also suspect that
they would burn thru more quickly than the thicker rubber/steel
braid/rubber hoses at half the price.
Again, I have no idea about the Europa fuel valve, but the originally
spec'd fuel selector valve for the Long EZ had insurmountable problems
with getting stiffer and eventually seizing. After years and many 'special'
lubes, the real solution was to replace the valve, which had a tapered
brass plug running in a brass bore, with a better design. The current
recommended valve has an aluminum body and straight cylindrical
spool sealed with o-rings. It has dual ball detents for reliability and
positive positioning. Tapered plug brass-on-brass valves, IMHO, have
no place in your airplane. I have looked at Andair's valves and gascolators
and was very impressed with the apparent quality, altho they are
expensive. I have not used them so am only going on appearances.
The interlock on the "off" position seems like a good idea, altho I
have never need it, it can't hurt unless you are on fire and can't
get it turned off quickly enough.
I'm not sure what a PFA mod approval is - I assume some sort of
gov't approval. Too bad, we can put anything we want to in our
homebuilts in the US - altho freedom is wonderful, a lot of the
reason I spend time on this newsletter is that I hope I might save
someone some money or even avoid a serious problem. If you
need some sort of gov't blessing, I would involve them early on
to avoid any course reversals and wasted money and time.
I like the sight guages in the Long EZ, altho ocassionally the
shaded one is hard to see in extremely bright sunlight. Remember,
they are about 4 ft away over your shoulder. They
don't fail and are always accurate. I have heard that some
sight guages are not as good, but it seems if the system has
a very small hole it will dampen out oscillations.
Bill
Long EZ builder & pilot
mechanical engineer
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