I spoke to the tech rep at Walbro regarding the wobble plate blockage.
His reply was that Yes, the stopped wobble plate can block the free
flow of fuel to the second pump in series. But, the blockage can be
overcome by 1.5 psi of push or suction.


On Mon, 12 Apr 2004 15:43:41 GMT, Rich Hampel
wrote:

The Walbro is a 'wobble plate' diaphragm and therefore not suitable for
series installation. If the wobble plate stops in a position such
that one pump is blocked then both pumps will not flow.

For parallel installation application - a simple thumb-cock on the
outlet of each pump would be sufficient.


In article , Kelton Joyner
wrote:

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