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Default Parallelling fuel pumps --- better to use a 'day tank'

Just my experience in using Walbro pumps in recirculation systems,
pulling through 2 filters instead of pushing. Not sure amp draw, but
going on 3 years now 100% running with shut-downs only when I really
want it quite. (maybe 50-100hr out of a year).

One pump, still a ticking :-)

-al-


On Tue, 13 Apr 2004 00:41:24 GMT, Rich Hampel
wrote:

Just my experience in using Walbro pumps in recirculation systems. But
to be fair Im pushing a hefty differential pressure through a major
filter bank. With a 6 psid load I only get ~700 hrs. on my Walbro
pumps, I havent measured the amps draw but I wager its 50% of rated amp
capacity.

In article , Doug Dotson
wrote:

Interesting. Can you point me to some supporting docs that
indicates the WALBRO is not suitable as a primary pump.
This is counter to all I have heard from numerous sources
including reputable marine service outfits. Actually, the
WALBRO docs that come with the pump includes only
instructions for installing it as a list pump.

More below.

Doug
s/v Callista

"Rich Hampel" wrote in message
...
Instead of parelleling electrical lift pumps, better to install a 'day
tank' that is constantly supplied by freshly filtered fuel oil but with
a lock-out cock (to an inverted dip tube in the day tank) so that the
day tank always keeps a full load of fuel. Then if you have electrical
failure or filter blockage you will be able to use the 3 or 4 gallons
in the day tank to keep moving and make repairs, etc. If worse
becomes worse, you can always siphon fuel from the main tank(s) and
manually load a gravity feed 'day tank'.


Not practical in my case.

FWIW ... A Walbro IMHO is NOT a constant duty delivery pump.


Not my understanding. This pump seems to have been used for many
years as a primary fuel pump and seems to have a very reputation.

A better
solution for that application is simply an automotive 12v impulse fuel
pump. The Walbro is an intermittent transfer or recirculation pump;
but, can be so piped that if the engine mounted diaphragm lift pump AND
the inline priming pump BOTH fail then the recirculation pump can be
used to either pressurize the system or deliver to the 'day tank'.


That is sort of what I have now. Engine mounted mechanical lift
pump with the WALBRO ahead of it. WALBRO can be used
as a backup in the case of a failure although some plumbing
has to be moved to bypass a failed mechanical pump.