Fuel transfer/polishing pump
 

LaBomba182 wrote:

Subject: Fuel transfer/polishing pump
From: Jere Lull


You don't want too fine a filter on the suction side. On Yanmars (and
others), the lift pump can fail sooner due to the restriction.



My point is if you use a large surface area small micron filter and change it
regularly, you should never see high suction pressures.


If you do both, it's better, of course. We balance cost in there
someplace, of course. I figure a new 30-micron filter will have one
third (or 1/9th?) the resistance, switching up to a 900 would only
(about) halve it. When there's a bit of dirt, though, the 30 micron
filter will clog less while still protecting the lift pump.

The idea
is to do the cleaning in stages: 30 micron before the lift pump, 10
micron just before the high pressure pump. That said, we used 10 micron
Racor elements for 8-9 seasons and 1000 hours with no significant ill
effects except when we got a shot of algae.



8-9 years without changing the element! Your perpetuating a stereo type Jere.
:-)


You're right, that wasn't entirely clear. We change the filters each
spring as cheap insurance. I haven't noticed any discoloration in the
primary filter or bowl except when I brushed the Racor during the algae
incident, and that could well have been my mishandling.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

The memo from Yanmar (via Mack Boring) didn't make any distinction
on type of filter. Just the porosity on the element. Perhaps it was a CYA
move to specify anything smaller than 30 uM.


If that's the case, then you have to do what they say.
At least until the warranty runs out. :-)

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

The memo from Yanmar (via Mack Boring) didn't make any distinction
on type of filter. Just the porosity on the element. Perhaps it was a CYA
move to specify anything smaller than 30 uM.


If that's the case, then you have to do what they say.
At least until the warranty runs out. :-)

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: Jere Lull

I figure a new 30-micron filter will have one
third (or 1/9th?) the resistance, switching up to a 900 would only
(about) halve it.

I would guess much less than that. Based on the surface area of a 900.

You're right, that wasn't entirely clear. We change the filters each
spring as cheap insurance.


Got it. :-)

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: Jere Lull

I figure a new 30-micron filter will have one
third (or 1/9th?) the resistance, switching up to a 900 would only
(about) halve it.

I would guess much less than that. Based on the surface area of a 900.

You're right, that wasn't entirely clear. We change the filters each
spring as cheap insurance.


Got it. :-)

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Huh? Bubbling up fuel? It helps it as much as drawing the fuel from
one baffled area into the engine. Better to draw it into a polishing
system for a while.

But unless the fuel is shaken up real well most of the crud is still at the
bottom of each baffled area in a nice little mound.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Huh? Bubbling up fuel? It helps it as much as drawing the fuel from
one baffled area into the engine. Better to draw it into a polishing
system for a while.

But unless the fuel is shaken up real well most of the crud is still at the
bottom of each baffled area in a nice little mound.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Len Krauss"

No offense -- but have you?

Yes, many times.

They're are not solid top to bottom as you seem
to suggest.

Never suggested that.
I assumed it was understood that there would have to be a way for the fuel to
travel from one baffled area to the next.


The plate bottoms, in particular, usually have tunnels.


More like notches.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Len Krauss"

No offense -- but have you?

Yes, many times.

They're are not solid top to bottom as you seem
to suggest.

Never suggested that.
I assumed it was understood that there would have to be a way for the fuel to
travel from one baffled area to the next.


The plate bottoms, in particular, usually have tunnels.


More like notches.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Have to have tunnels between the baffles.


Yes.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Have to have tunnels between the baffles.


Yes.

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Yes, but it is better than nothing.


At least for that one baffled area. Which may be on the far side of the tank
away from the pickup. :-)

Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Yes, but it is better than nothing.


At least for that one baffled area. Which may be on the far side of the tank
away from the pickup. :-)

Capt. Bill

Fuel transfer/polishing pump
 

Invalid statement. In one case you are talking about lubrication oil,
in the other your are talking about fuel. A diesel will run quite a
long time without changing the oil just a s gas engine will.

Doug

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with
dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Capt. Bill

Fuel transfer/polishing pump
 

Invalid statement. In one case you are talking about lubrication oil,
in the other your are talking about fuel. A diesel will run quite a
long time without changing the oil just a s gas engine will.

Doug

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with
dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Capt. Bill

Fuel transfer/polishing pump
 

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Doug
s/v Callista

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Huh? Bubbling up fuel? It helps it as much as drawing the fuel from
one baffled area into the engine. Better to draw it into a polishing
system for a while.

But unless the fuel is shaken up real well most of the crud is still at
the
bottom of each baffled area in a nice little mound.

Capt. Bill

Fuel transfer/polishing pump
 

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Doug
s/v Callista

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Huh? Bubbling up fuel? It helps it as much as drawing the fuel from
one baffled area into the engine. Better to draw it into a polishing
system for a while.

But unless the fuel is shaken up real well most of the crud is still at
the
bottom of each baffled area in a nice little mound.

Capt. Bill

Fuel transfer/polishing pump
 

If it is away from the pickup, then it isn't entering into the problem.
If things get stirred up then the polishing system will do its job
better.

Doug

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Yes, but it is better than nothing.


At least for that one baffled area. Which may be on the far side of the
tank
away from the pickup. :-)

Capt. Bill

Fuel transfer/polishing pump
 

If it is away from the pickup, then it isn't entering into the problem.
If things get stirred up then the polishing system will do its job
better.

Doug

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

Yes, but it is better than nothing.


At least for that one baffled area. Which may be on the far side of the
tank
away from the pickup. :-)

Capt. Bill

Fuel transfer/polishing pump
 

I assumed it was understood that there would have to be a way for the fuel
to
travel from one baffled area to the next.

And hence the crud as well.

Doug

Fuel transfer/polishing pump
 

I assumed it was understood that there would have to be a way for the fuel
to
travel from one baffled area to the next.

And hence the crud as well.

Doug

Fuel transfer/polishing pump
 

After having my lift pump fail half way across the Gulf Stream, I think
I'll stick to what Yanmar and the mechanic in FL suggested even
beyond the warranty.

Doug
s/v Callista

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

The memo from Yanmar (via Mack Boring) didn't make any distinction
on type of filter. Just the porosity on the element. Perhaps it was a CYA
move to specify anything smaller than 30 uM.


If that's the case, then you have to do what they say.
At least until the warranty runs out. :-)

Capt. Bill

Fuel transfer/polishing pump
 

After having my lift pump fail half way across the Gulf Stream, I think
I'll stick to what Yanmar and the mechanic in FL suggested even
beyond the warranty.

Doug
s/v Callista

"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

The memo from Yanmar (via Mack Boring) didn't make any distinction
on type of filter. Just the porosity on the element. Perhaps it was a CYA
move to specify anything smaller than 30 uM.


If that's the case, then you have to do what they say.
At least until the warranty runs out. :-)

Capt. Bill

Fuel transfer/polishing pump
 

On 03 Dec 2003 03:39:16 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Yeah, but after that Chevy 350 engine runs for years with dirty oil,
you'll probably find that the bearing surfaces are more prematurely worn
than the oil pump. The reason is that the bearing surfaces are speced
to operate with clean, filtered lubricating oil. After years of
running, the filter has probably clogged so much that it's always in
bypass mode, and maybe even torn, allowing all the dirt to wear the
bearings. The oil pump, on the other hand (and unlike a fuel injector
pump) is designed to run in dirty oil... so it's tolerances have to be
less. All dirt trapped in the lubricating oil filter has already passed
through the oil pump.

And *that* is why your statement above is a red herring, because the
lubricating pump always pumps pre-filtered oil so it matters very little
what the filter is doing.

By the way, instead of saying "But that's a red herring since it's not
usually the oil pump that wears out due to dirty lubricating oil." I
should have said "But that's a red herring since it's not usually the
oil pump that wears out *prematurely" due to dirty lubricating oil."

Steve

Fuel transfer/polishing pump
 

On 03 Dec 2003 03:39:16 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Yeah, but after that Chevy 350 engine runs for years with dirty oil,
you'll probably find that the bearing surfaces are more prematurely worn
than the oil pump. The reason is that the bearing surfaces are speced
to operate with clean, filtered lubricating oil. After years of
running, the filter has probably clogged so much that it's always in
bypass mode, and maybe even torn, allowing all the dirt to wear the
bearings. The oil pump, on the other hand (and unlike a fuel injector
pump) is designed to run in dirty oil... so it's tolerances have to be
less. All dirt trapped in the lubricating oil filter has already passed
through the oil pump.

And *that* is why your statement above is a red herring, because the
lubricating pump always pumps pre-filtered oil so it matters very little
what the filter is doing.

By the way, instead of saying "But that's a red herring since it's not
usually the oil pump that wears out due to dirty lubricating oil." I
should have said "But that's a red herring since it's not usually the
oil pump that wears out *prematurely" due to dirty lubricating oil."

Steve

Fuel transfer/polishing pump
 

On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

Doug
s/v Callista

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

Doug
s/v Callista

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

Pretty sure I posted a link early in this conversation that shows a diagram
of a polishing system based on a GCF F-1 filter that allows either polishing
or running with the F-1 as the first filter before going into the Racor
while running. If I didn't, or you can't find it, here it is again:
http://www.trawlerworld.com/features_06.htm

"Doug Dotson" wrote in message
...
That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

Doug
s/v Callista

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

Pretty sure I posted a link early in this conversation that shows a diagram
of a polishing system based on a GCF F-1 filter that allows either polishing
or running with the F-1 as the first filter before going into the Racor
while running. If I didn't, or you can't find it, here it is again:
http://www.trawlerworld.com/features_06.htm

"Doug Dotson" wrote in message
...
That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

Doug
s/v Callista

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

On Wed, 3 Dec 2003 17:21:58 -0500, "Doug Dotson" wrote:

That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

I guess I don't understand your system. Why would it require two
independent polishing systems? Even with a single set of filters (GCF
fillowed by Racor) you can use valves and piping to plumb the thing any
way you want.

Steve

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

On Wed, 3 Dec 2003 17:21:58 -0500, "Doug Dotson" wrote:

That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

I guess I don't understand your system. Why would it require two
independent polishing systems? Even with a single set of filters (GCF
fillowed by Racor) you can use valves and piping to plumb the thing any
way you want.

Steve

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson" wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished" fuel.

Steve

Fuel transfer/polishing pump
 

Steve,

I understood that you were suggesting that I leave the polishing system
running while running the engine. Since I have 2 tanks it seems to me
to require two polishing systems to keep polishing while running. The
system I have designed allows me to polish either of the two tanks
at any time and run the engine out of either tank at any time as well. So
I can polish the same one I am running out of if I wish. I guess the
choice of which to polish while running is up for grabs.

Doug
s/v Callista

"Steven Shelikoff" wrote in message
...
On Wed, 3 Dec 2003 17:21:58 -0500, "Doug Dotson" wrote:

That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

I guess I don't understand your system. Why would it require two
independent polishing systems? Even with a single set of filters (GCF
fillowed by Racor) you can use valves and piping to plumb the thing any
way you want.

Steve

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson"
wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished"
fuel.

Steve

Fuel transfer/polishing pump
 

Steve,

I understood that you were suggesting that I leave the polishing system
running while running the engine. Since I have 2 tanks it seems to me
to require two polishing systems to keep polishing while running. The
system I have designed allows me to polish either of the two tanks
at any time and run the engine out of either tank at any time as well. So
I can polish the same one I am running out of if I wish. I guess the
choice of which to polish while running is up for grabs.

Doug
s/v Callista

"Steven Shelikoff" wrote in message
...
On Wed, 3 Dec 2003 17:21:58 -0500, "Doug Dotson" wrote:

That would require me to have 2 pretty much independent polishing
systems. I don't really have the room for that and the extra
expense would be hard to justify.

I guess I don't understand your system. Why would it require two
independent polishing systems? Even with a single set of filters (GCF
fillowed by Racor) you can use valves and piping to plumb the thing any
way you want.

Steve

"Steven Shelikoff" wrote in message
...
On Tue, 2 Dec 2003 23:41:45 -0500, "Doug Dotson"
wrote:

That may be true, and as long as it stays there the engine still
runs fine. If it does get shaken up, the a polishing system will
do its job while lessing the crud going through the engine filtering
system. Once initial polishing is done, I will be alternating between
tanks. One running while the other polishing. Getting things shaken
up is the best thing I can hope for.

Why not just always leave the polishing system in-line? Allow for a
bypass to change a filter or if it develops a vacuum leak, but other
then that, there's nothing wrong with always using "just polished"
fuel.

Steve

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"



"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with
dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Capt. Bill

Invalid statement.

Really? Without foundation. How so?

Are you saying a diesel will run a long time with dirty fuel?

In one case you are talking about lubrication oil,
in the other your are talking about fuel.

Correct. But that does that make those statements "invalid"?

A diesel will run quite a
long time without changing the oil just a s gas engine will.

Of course it will.
But that has no relation to how long it will run with dirty or poorly filtered
fuel. Other than to back up just what I was saying, that lubricating oil does
not need to be filtered as well as fuel oil to keep a fuel injected engine
running.


Capt. Bill

Fuel transfer/polishing pump
 

Subject: Fuel transfer/polishing pump
From: "Doug Dotson"



"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From:

On 29 Nov 2003 20:48:01 GMT, (LaBomba182) wrote:

Subject: Fuel transfer/polishing pump
From: (Steven Shelikoff)

Not much difference between diesel and oil.

Perhaps, but there is a world of difference between the tolerances of a
fuel
injector pump and an oil pump.

True. But that's a red herring since it's not usually the oil pump that
wears out due to dirty lubricating oil.

Not quite. A 350 Chevy engine will run for a long time, years maybe, with
dirty
oil.
A diesel injection pump and/or injectors with dirty fuel will not.

Capt. Bill

Invalid statement.

Really? Without foundation. How so?

Are you saying a diesel will run a long time with dirty fuel?

In one case you are talking about lubrication oil,
in the other your are talking about fuel.

Correct. But that does that make those statements "invalid"?

A diesel will run quite a
long time without changing the oil just a s gas engine will.

Of course it will.
But that has no relation to how long it will run with dirty or poorly filtered
fuel. Other than to back up just what I was saying, that lubricating oil does
not need to be filtered as well as fuel oil to keep a fuel injected engine
running.


Capt. Bill

Fuel transfer/polishing pump
 

On Wed, 3 Dec 2003 21:10:23 -0500, "Doug Dotson" wrote:

Steve,

I understood that you were suggesting that I leave the polishing system
running while running the engine. Since I have 2 tanks it seems to me
to require two polishing systems to keep polishing while running. The
system I have designed allows me to polish either of the two tanks
at any time and run the engine out of either tank at any time as well. So
I can polish the same one I am running out of if I wish. I guess the
choice of which to polish while running is up for grabs.

I think I'd route it so that I can route either tank to the polishing
system then 'T' the polishing system to the engine and the return to
either tank. Just make sure you're returning to the same tank you're
drawing from. A simplified version (without bypass plumbing which is a
pain to draw) looks something like this: (view with fixed point font
like courier)

-------------- /--------------------------T---------|
| Y select / return to tanks | |
---------- | --------------- |
| | |(to tank 2) | check valve | |
| Tank 1 | --------------- |
| |---------- ------------- | |
---------- | | Polishing | -------- | ----------
|from | filters | | | | \ | |
Y select /----| with |-| Pump |-T- \-| Engine |
---------- /tanks| bypassing | | | | |
| | | ------------- -------- ----------
| Tank 2 | |
| |----------
---------- out

If the above ascii drawing looks horrible, sorry.:) But basically, the
supply from both tanks goes to a Y valve which feeds either to the
polishing filters. That's where you'd put the bypass valves so you can
go around any filter (GCF or Racor). Then to a T where one side goes to
a shutoff valve then to the engine. The shutoff valve is so that you
can turn off fuel to the engine while you're priming the system after
changing filters so air won't get in the engine. You can also plumb it
so that the engine can draw from the tanka bypassing the filters so you
can prime them and run the engine at the same time if that's a
requirement. I didn't care about that since I don't run the engine all
that much (sailboat.) Also not shown is that you want to install vacuum
gauges, one before the GCF filter, one between the GCF and the Racor and
one after the Racor before the Walbro pump. Any difference more than a
few psi across a filter means it's time for an element change.

The other side of the T goes to a check valve. That's there so that if
the electric pump fails the engine won't suck air from the return lines.
Then there's a T where the engine return and the polishing system return
join and go to another Y valve to select where to return the fuel to.
Just make sure both Y valves are in the same position. You can also use
this as a fuel transfering pump if you want to, by putting the Y valves
in different positions. But be careful you don't overflow the tank
being filled.

Steve