Fred Klein wrote:
> There's a notation at the bottom of the page stating that "the above"
> fuel pumps "do not feature an anti-siphoning valve and fuel will flow
> through them in event of pump failure". That would seem to indicate that
> if using two of them, they should be installed in series rather than
> parallel in order to avoid loss of fuel pressure by having the operative
> pump pumping fuel back thru the failed pump instead of to the engine.
I would install them in the same way as recommended with the Europa
engine. That is, in series with two external one-way valves. The one-way
valves act as a bypass for the non-functioning fuel pump.
Why, you might ask, the fuel pumps flow through anyway? Well, if a fuel
pump is broken, you can't count on anything. Maybe just the motor gave
up the ghost, but it is also possible that a vane broke off and is now
blocking the stream, or the axle broke and the entire pump section
scattered in pieces, or something downstream of the filter got loose and
plugged the pump, or whatever. The fuel pump might let the fuel through,
but it might also not. If all this could never happen, you didn't need a
secondary fuel pump anyway. Just make sure that if you take one fuel
pump completely out of the equation, you can still get fuel to the engine.
Frans
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