The internal filter on the Walbro can be cleaned. In fact, they supply
a spare with the pump. Taking the pump apart is a little fussy in an
emergency situation. I am a little concerned to find out that a pump
failure may result in a blocked fuel supply due to the wobble plate.
Right now, I have the Walbro in line with my mechanical pump.


On Mon, 12 Apr 2004 17:55:34 -0400, "Doug Dotson"
wrote:

I seem to recall from the WALBRO docs that the pump is not
field servicable. Specifically, it states that the internal filters
cannot be changed.

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

Steve
Exactly what does the spec say? Is it NPSH ( nett positive suction head) of
1 ft? Or is it max lift of one foot? It almost sounds like a self priming
manual pump of some sort might be the go.
DF
"Steve" wrote in message
...

"Doug Dotson" wrote in message
...
Is it possible/advisable to place 2 WALBRO fuel pumps
in parallel without any valves? My goal is to be able
to switch between pumps by just applying power to one
or the other without having to adjust valves.


I'm not familiar with the WALBRO pumps, but I would assume that they are
positive displacement pumps and therefore would have valves that would act
as check valves.

However, I would recommend inline check valves in the discharge of each to
keep the service pressure off these valves and the pump chamber. No sense
subjecting the idle pump to service pressure if unnecassary.

I'm preparing to install a lift pump in series with my engine pump to
assist
in priming both the engine and the generator after I change filters.
Unfortunately the pump I purchased (AC) can only lift 1 ft., according to
the specs. Tha't ridiculous IMHO... My tanks are all down in the keels and
the lift for my service/day tank would be about 30 inches when the tank is
low. Sorry, didn't mean to bring my problems into your post.

Steve
s/v Good Intentions

Steve
Exactly what does the spec say? Is it NPSH ( nett positive suction head) of
1 ft? Or is it max lift of one foot? It almost sounds like a self priming
manual pump of some sort might be the go.
DF
"Steve" wrote in message
...

"Doug Dotson" wrote in message
...
Is it possible/advisable to place 2 WALBRO fuel pumps
in parallel without any valves? My goal is to be able
to switch between pumps by just applying power to one
or the other without having to adjust valves.


I'm not familiar with the WALBRO pumps, but I would assume that they are
positive displacement pumps and therefore would have valves that would act
as check valves.

However, I would recommend inline check valves in the discharge of each to
keep the service pressure off these valves and the pump chamber. No sense
subjecting the idle pump to service pressure if unnecassary.

I'm preparing to install a lift pump in series with my engine pump to
assist
in priming both the engine and the generator after I change filters.
Unfortunately the pump I purchased (AC) can only lift 1 ft., according to
the specs. Tha't ridiculous IMHO... My tanks are all down in the keels and
the lift for my service/day tank would be about 30 inches when the tank is
low. Sorry, didn't mean to bring my problems into your post.

Steve
s/v Good Intentions

The lift pump in my case is only pulling through a Raycor and the
on-engine filter.

Doug
s/v Callista

"Rich Hampel" wrote in message
...
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.

The lift pump in my case is only pulling through a Raycor and the
on-engine filter.

Doug
s/v Callista

"Rich Hampel" wrote in message
...
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.

On Mon, 12 Apr 2004 13:33:26 -0000, 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?

Then I wouldn't put them in parallel without isolation valves. Even if
it works when both pumps are good, you don't know how the pump will
fail.

Steve

On Mon, 12 Apr 2004 13:33:26 -0000, 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?

Then I wouldn't put them in parallel without isolation valves. Even if
it works when both pumps are good, you don't know how the pump will
fail.

Steve

Both my WALBRO pumps came with no replacement filters. A
large box in bold print in the instructions states the following:

" SERVICE DATA
The Walbro Marine Electronic Pump incorporates
two (2) built-in filters, one for filtering fine particles
and the other (a magnet) for trapping metalic
particles. Due to the construction of the protective
outer shell, these filters cannot be serviced."

The plastic outer shell appears to be glued together.
Perhaps this is a newer or different model than the
one you have.

Doug
s/v Callista

:
"Marc" wrote in message
...
The internal filter on the Walbro can be cleaned. In fact, they supply
a spare with the pump. Taking the pump apart is a little fussy in an
emergency situation. I am a little concerned to find out that a pump
failure may result in a blocked fuel supply due to the wobble plate.
Right now, I have the Walbro in line with my mechanical pump.


On Mon, 12 Apr 2004 17:55:34 -0400, "Doug Dotson"
wrote:

I seem to recall from the WALBRO docs that the pump is not
field servicable. Specifically, it states that the internal filters
cannot be changed.

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

Both my WALBRO pumps came with no replacement filters. A
large box in bold print in the instructions states the following:

" SERVICE DATA
The Walbro Marine Electronic Pump incorporates
two (2) built-in filters, one for filtering fine particles
and the other (a magnet) for trapping metalic
particles. Due to the construction of the protective
outer shell, these filters cannot be serviced."

The plastic outer shell appears to be glued together.
Perhaps this is a newer or different model than the
one you have.

Doug
s/v Callista

:
"Marc" wrote in message
...
The internal filter on the Walbro can be cleaned. In fact, they supply
a spare with the pump. Taking the pump apart is a little fussy in an
emergency situation. I am a little concerned to find out that a pump
failure may result in a blocked fuel supply due to the wobble plate.
Right now, I have the Walbro in line with my mechanical pump.


On Mon, 12 Apr 2004 17:55:34 -0400, "Doug Dotson"
wrote:

I seem to recall from the WALBRO docs that the pump is not
field servicable. Specifically, it states that the internal filters
cannot be changed.

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

The plastic shell is capped at both ends. Pry off the caps and the
shell falls apart, exposing the pump inside.
I am presently trying to contact Walbro about the fuel pass thru
question. The info I have to date from the mfg. is the following:
Model 6802, continuous duty (10k+ hrs) electronic fuel pump, 420
micron mesh filter, magnetic filter, 7psi, 40gph. Everyone I have
spoken to to date states that the engine pump should be able to suck
fuel through a non operational Walbro, but I have not received an
answer yet from a specific engineering source.

On Tue, 13 Apr 2004 08:56:24 -0400, "Doug Dotson"
wrote:

Both my WALBRO pumps came with no replacement filters. A
large box in bold print in the instructions states the following:

" SERVICE DATA
The Walbro Marine Electronic Pump incorporates
two (2) built-in filters, one for filtering fine particles
and the other (a magnet) for trapping metalic
particles. Due to the construction of the protective
outer shell, these filters cannot be serviced."

The plastic outer shell appears to be glued together.
Perhaps this is a newer or different model than the
one you have.

Doug
s/v Callista

:
"Marc" wrote in message
.. .
The internal filter on the Walbro can be cleaned. In fact, they supply
a spare with the pump. Taking the pump apart is a little fussy in an
emergency situation. I am a little concerned to find out that a pump
failure may result in a blocked fuel supply due to the wobble plate.
Right now, I have the Walbro in line with my mechanical pump.


On Mon, 12 Apr 2004 17:55:34 -0400, "Doug Dotson"
wrote:

I seem to recall from the WALBRO docs that the pump is not
field servicable. Specifically, it states that the internal filters
cannot be changed.

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