Hi Paul
" Can anyone tell me why rotax swapped from parallel to series arrangement
for the 914 fuel pumps."
To keep differential fuel pressure (pressure to carb float bowls over
airbox pressure) less than I think 5 PSI.
Parallel will blow over that number and has chance of overcoming ability
of needle valve and seat to hold it back.
Also when operating on two pumps in parallel, it is harder on each pump
compared to operating two pumps series with bypass.
Note Europa has modified Rotax recommendation by installing a second
filter, great idea IMHO.
I have details of my system here:
http://www.europaowners.org/modules.php?set_albumName=album231&op=modload&name=gallery&file=index&include=view_album.php
Gilles was kind enough to put up fuel pump testing on his website, link
provided in above link.
There is a diagram on Gilles website that is easier to follow than what
Europa has in their FWF manual, but it is the same. I only substituted two
Andair 375 gasculators for supplied filters.
Ron Parigoris
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