Doug,

The way the Walbro is built, the flow may or may not be blocked
depending on the position that the wobble plate is in. Bottom line if
you want fully automatic change over for backup, plumb them in parallel
with a check valve on the output of each. Then you can wire them to a
SPDT center off switch to shift from one to the other.

Doug Dotson wrote:
Is there no failure mode that would prevent flow through?

Doug
s/v Callista

"Kelton Joyner" wrote in message
.. .

Unless you have isolation valves to allow servicing of a parallel pump,
series works just as well for backup.
fuel wil flow through the unpowered pump.
Kelton
W4IND
s/v Isle Escape

Larry W4CSC wrote:

(Steven Shelikoff) wrote in
:



That begs the question why are you going to put two pumps in parallel if
you only want to run one at a time?

Steve



Backup?

Larry W4CSC




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