|
Parallelling fuel pumps
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 |
Parallelling fuel pumps
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 |
Parallelling fuel pumps
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 |
Parallelling fuel pumps --- better to use a 'day tank'
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. |
Parallelling fuel pumps --- better to use a 'day tank'
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. |
Parallelling fuel pumps
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 |
Parallelling fuel pumps
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 |
Parallelling fuel pumps
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 |
Parallelling fuel pumps
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 |
Parallelling fuel pumps
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 |
Parallelling fuel pumps
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 |
Parallelling fuel pumps
Well, my engine pump has been drawing fuel through a
Wabro for over a year now with no I'll effects. Doug s/v Callista "Marc" wrote in message ... 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 |
Parallelling fuel pumps
Well, my engine pump has been drawing fuel through a
Wabro for over a year now with no I'll effects. Doug s/v Callista "Marc" wrote in message ... 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 |
Parallelling fuel pumps
That is my concern. I think I will install both check valves
and isolation valves as well. Doug s/v Callista "Steven Shelikoff" wrote in message ... 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 |
Parallelling fuel pumps
That is my concern. I think I will install both check valves
and isolation valves as well. Doug s/v Callista "Steven Shelikoff" wrote in message ... 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 |
Parallelling fuel pumps
Further thoughts against paralleling such pumps:
If the internal check valves in one pump fails then the fluid will flow retrograde in the pump that failed.... and damn little volume is pumped by the pump that remains intact. Typical industrial installation of such a 'system' would require a block and bypass system of cocks/valves and bypass/lock-out piping. In article , Steven Shelikoff wrote: 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 |
Parallelling fuel pumps
Further thoughts against paralleling such pumps:
If the internal check valves in one pump fails then the fluid will flow retrograde in the pump that failed.... and damn little volume is pumped by the pump that remains intact. Typical industrial installation of such a 'system' would require a block and bypass system of cocks/valves and bypass/lock-out piping. In article , Steven Shelikoff wrote: 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 |
Parallelling fuel pumps
Dont need check valves if you install isolation valves.
In article , Doug Dotson wrote: That is my concern. I think I will install both check valves and isolation valves as well. Doug s/v Callista "Steven Shelikoff" wrote in message ... 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 |
Parallelling fuel pumps
Dont need check valves if you install isolation valves.
In article , Doug Dotson wrote: That is my concern. I think I will install both check valves and isolation valves as well. Doug s/v Callista "Steven Shelikoff" wrote in message ... 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 |
Parallelling fuel pumps
Must be a 'new' version as all my Walbro pumps have
accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
Must be a 'new' version as all my Walbro pumps have
accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps --- better to use a 'day tank'
And whats the amperage draw (heat load) when the pump is stalled/dead-headed vs. a blocked filter? In article , Doug Dotson wrote: 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. |
Parallelling fuel pumps --- better to use a 'day tank'
And whats the amperage draw (heat load) when the pump is stalled/dead-headed vs. a blocked filter? In article , Doug Dotson wrote: 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. |
Parallelling fuel pumps --- better to use a 'day tank'
It just shuts off when it reaches pressure so draw is zero.
Doug s/v Callista "Rich Hampel" wrote in message ... And whats the amperage draw (heat load) when the pump is stalled/dead-headed vs. a blocked filter? In article , Doug Dotson wrote: 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. |
Parallelling fuel pumps --- better to use a 'day tank'
It just shuts off when it reaches pressure so draw is zero.
Doug s/v Callista "Rich Hampel" wrote in message ... And whats the amperage draw (heat load) when the pump is stalled/dead-headed vs. a blocked filter? In article , Doug Dotson wrote: 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. |
Parallelling fuel pumps
It appears these do not. Just to remove the mounting bracket
one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
It appears these do not. Just to remove the mounting bracket
one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
I want to be able to switch pumps with the flick
of a switch not crawling into the engine compartment to switch valves. Doug s/v Callista "Rich Hampel" wrote in message ... Dont need check valves if you install isolation valves. In article , Doug Dotson wrote: That is my concern. I think I will install both check valves and isolation valves as well. Doug s/v Callista "Steven Shelikoff" wrote in message ... 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 |
Parallelling fuel pumps
I want to be able to switch pumps with the flick
of a switch not crawling into the engine compartment to switch valves. Doug s/v Callista "Rich Hampel" wrote in message ... Dont need check valves if you install isolation valves. In article , Doug Dotson wrote: That is my concern. I think I will install both check valves and isolation valves as well. Doug s/v Callista "Steven Shelikoff" wrote in message ... 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 |
Parallelling fuel pumps
So perhaps a valve on both ends plus a check valve or maybe
two check valves. This is getting too complicated to be worth it. Doug s/v Callista "Rich Hampel" wrote in message ... Further thoughts against paralleling such pumps: If the internal check valves in one pump fails then the fluid will flow retrograde in the pump that failed.... and damn little volume is pumped by the pump that remains intact. Typical industrial installation of such a 'system' would require a block and bypass system of cocks/valves and bypass/lock-out piping. In article , Steven Shelikoff wrote: 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 |
Parallelling fuel pumps
So perhaps a valve on both ends plus a check valve or maybe
two check valves. This is getting too complicated to be worth it. Doug s/v Callista "Rich Hampel" wrote in message ... Further thoughts against paralleling such pumps: If the internal check valves in one pump fails then the fluid will flow retrograde in the pump that failed.... and damn little volume is pumped by the pump that remains intact. Typical industrial installation of such a 'system' would require a block and bypass system of cocks/valves and bypass/lock-out piping. In article , Steven Shelikoff wrote: 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 |
Parallelling fuel pumps
"David Flew" wrote in message ... 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 This was an AC pulse type electric pump I got at the autoparts store. It's on the boat, haven't installed it yet. But I think it said Max. Suction Lift is one foot. I'm going to check it when I go there later today. Steve s/v Good Intentions |
Parallelling fuel pumps
"David Flew" wrote in message ... 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 This was an AC pulse type electric pump I got at the autoparts store. It's on the boat, haven't installed it yet. But I think it said Max. Suction Lift is one foot. I'm going to check it when I go there later today. Steve s/v Good Intentions |
Parallelling fuel pumps
You got the same ones as we have,Doug. Yes, you have to bend the
mounting bracket drastically. Pry off the end caps and the clam shell protection comes apart, exposing the pump. Remove three(?) screws on the bottom plate to expose the filter. http://www.autoperformanceengineerin...6000_pump.html On Tue, 13 Apr 2004 11:48:16 -0400, "Doug Dotson" wrote: It appears these do not. Just to remove the mounting bracket one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
You got the same ones as we have,Doug. Yes, you have to bend the
mounting bracket drastically. Pry off the end caps and the clam shell protection comes apart, exposing the pump. Remove three(?) screws on the bottom plate to expose the filter. http://www.autoperformanceengineerin...6000_pump.html On Tue, 13 Apr 2004 11:48:16 -0400, "Doug Dotson" wrote: It appears these do not. Just to remove the mounting bracket one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
Why do you think Walbro is lying about this?
Doug s/v Callista "Marc" wrote in message ... You got the same ones as we have,Doug. Yes, you have to bend the mounting bracket drastically. Pry off the end caps and the clam shell protection comes apart, exposing the pump. Remove three(?) screws on the bottom plate to expose the filter. http://www.autoperformanceengineerin...6000_pump.html On Tue, 13 Apr 2004 11:48:16 -0400, "Doug Dotson" wrote: It appears these do not. Just to remove the mounting bracket one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
Why do you think Walbro is lying about this?
Doug s/v Callista "Marc" wrote in message ... You got the same ones as we have,Doug. Yes, you have to bend the mounting bracket drastically. Pry off the end caps and the clam shell protection comes apart, exposing the pump. Remove three(?) screws on the bottom plate to expose the filter. http://www.autoperformanceengineerin...6000_pump.html On Tue, 13 Apr 2004 11:48:16 -0400, "Doug Dotson" wrote: It appears these do not. Just to remove the mounting bracket one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
I think it has to do with the integrity of the protective shell and
corporate liability. I don't know why one is required. Obviously they are the same pumps. Do you think it has something to do with mounting the pump in the engine compartment.? CG Reg? Corrosion issues?. In any event, my pump is located outside the engine compartment and I see no reason not to remove the shell. On Tue, 13 Apr 2004 12:18:06 -0400, "Doug Dotson" wrote: Why do you think Walbro is lying about this? Doug s/v Callista "Marc" wrote in message .. . You got the same ones as we have,Doug. Yes, you have to bend the mounting bracket drastically. Pry off the end caps and the clam shell protection comes apart, exposing the pump. Remove three(?) screws on the bottom plate to expose the filter. http://www.autoperformanceengineerin...6000_pump.html On Tue, 13 Apr 2004 11:48:16 -0400, "Doug Dotson" wrote: It appears these do not. Just to remove the mounting bracket one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
I think it has to do with the integrity of the protective shell and
corporate liability. I don't know why one is required. Obviously they are the same pumps. Do you think it has something to do with mounting the pump in the engine compartment.? CG Reg? Corrosion issues?. In any event, my pump is located outside the engine compartment and I see no reason not to remove the shell. On Tue, 13 Apr 2004 12:18:06 -0400, "Doug Dotson" wrote: Why do you think Walbro is lying about this? Doug s/v Callista "Marc" wrote in message .. . You got the same ones as we have,Doug. Yes, you have to bend the mounting bracket drastically. Pry off the end caps and the clam shell protection comes apart, exposing the pump. Remove three(?) screws on the bottom plate to expose the filter. http://www.autoperformanceengineerin...6000_pump.html On Tue, 13 Apr 2004 11:48:16 -0400, "Doug Dotson" wrote: It appears these do not. Just to remove the mounting bracket one would have to bend it out of shape quite drastically. I looked closely at the brass caps top and bottom and it does appear that they may be able to be pryed off. But in any case the instructions say the filters are not servicable and there are no spares or instructions for servicing provided. Doug s/v Callista "Rich Hampel" wrote in message ... Must be a 'new' version as all my Walbro pumps have accessible/removalbe/cleanable protection screens/strainer wire. In article , 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 |
Parallelling fuel pumps
"Doug Dotson" wrote in
: Glenn, That is pretty much what I was figuring on other than the check valves. Not sure I want a center off switch though. I would prefer that one or the other be on at all times. I'm also considering putting an hours-meter on each so that I can balance the use. Doug s/v Callista I'll also vote for a manual valve on both in parallel...... We're in a seaway, big waves. The pump goes into failure mode, we switch on the backup and are back in business. Wouldn't it be good if we could isolate the failed pump for repairs, remove/replace or tear it down for that new diaphram while the other pump has the load and the first mate or autopilot is driving? Sure would be nice to be able to get that failed pump offline while the boat's still underway for repairs. Can't do that on the series pumps without some crazy plumbing bypasses and lots of valves.... Larry W4CSC |
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