tonyk@kaon.co.nz wrote:
> The reason for the change to series based pumps is to bring the fuel pressure
down to that specified by Rotax. If you measure the differential fuel pressure
to airbox pressure as recommended then you'll find that the pressure delivered
by parallel pumps is too high.
I have them in parallel, and it would be a rather "Rube Goldberg" arrangement to
make them series. That's because I have (all in the trigear console tunnel)
a sump I made. It's attached to the front of the floor-mounted fuel valve and
has 2 outlets.
In a parallel setup, do you think cutting back the volts on the boost/emergency
pump will relieve the pressure? I was thinking a 3.9V 10W Zener diode (if I
can find 'em), parallel pair (reasonably matched in Vz) for redundancy. I know
I can test it for flow rate etc., but do you see a reason not to do this?
> Unless you intend retrofitting the UMA pressure sensor there is no need to
> change.
I think that don't come out quite right. [Wink] The 914 carbs may indeed
tolerate
excess pressure, but to restate what a famous football coach here once said,
"On any given Sunday....a carb may flood!"
Reg,
Fred F.
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