> Some very useful discussion on fuel systems recently. We are in the process of
significantly altering the suggested system along the lines of many of the
contributers
to this site. In particular we are fitting Andair kit (new gascolator
coming along to go with the Wilksch diesel ) and upgrading to aluminium fuel
lines and AN/JIC fittings (including new tank outlets). One thing concerns
me slightly, there has been much made recently of filters blocking particularly
early on. That and the fact that the factory now suggest separate filters for
each fuel outlet makes me worry about a fuel system which goes from tank outlet
to fuel selector and then to gascolator thus putting the filtration in the
final common pathway to the engine. The alternative is to go from each tank
outlet
to a separate gascolator and then from the two gascolators to the fuel selector,
or indeed to substitute the 'reserve' gascolator with an Andair in line
filter. This would seem to avoid the reliance on a !
single filtration device, but the down side would be some additional weight and
a more complex system (each gascolator would need an isolation valve to allow
the bowl and filter to be inspected without the fuel tank draining on our
shoes).
Sorry thats all so long winded - any opinions out there. Apologies to Graham
- you've already given me your words of wisdom.
The gascolator should not clog as easily as a filter, so the redundancy is
not needed (at least that is my current belief, if anyone can convince me
otherwise, please do so!). If you want to use two filters for the redundancy
then you might want to use the fully redundant fuel system described at:
ftp://www.avnet.co.uk/pub/europa/fuelsys.pdf.
This parallel fuel system has some very nice properties, but I decided that
the factory system with a single gascolator was simpler.
By the way, where do you get aluminum line and fittings to upgrade to? I
checked Aircraft Spruce and Wicks, and neither had anything of the sort under
"fuel lines".
> Second question. Tank outlet access panels. The manual describes making these
100 mm panels by laying up splash mouldings and cutting back foam core etc.
There
is no mention of the two round 140mm recessed areas in the fuselage floor
immediately below where the tank outlets will lie. These do not appear to have
a foam core and are not flush with the rest of the fuselage. Am I missing
soething
here?
The later fuselage mouldings had the panels already marked out and ready to
cut out. My fuselage had rectangular recesses, are your's circular? In my
case I cut out the recess, leaving about a 1/2 inch lip. I then cut a
plywood panel and invented a piano wire holding mechanism. I think that the
XS manual was upgraded to talk about the new fuselage, did you miss a manual
update?
Brian
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