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.

Doug

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

Because small filters ahead of the lift pump stress the pump and cause
premature failure. No fun.


Not if you run a large enough (as in surface area) filter and change it
regularly. At 1 - 5 gph through a Racor 900 I don't see how you could over
stress a well built lift pump.


Capt. Bill

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.

Doug


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

Not sure that matters much. If the fuel can negoatiate the baffles
then I suspect the crud can as well. Hence the problem. Once the
fuel is shaken not stirred


Yes, but just bubbling up the fuel in one baffled area doesn't cut it.

Capt. Bill

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.

Doug


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

Not sure that matters much. If the fuel can negoatiate the baffles
then I suspect the crud can as well. Hence the problem. Once the
fuel is shaken not stirred


Yes, but just bubbling up the fuel in one baffled area doesn't cut it.

Capt. Bill

Have to have tunnels between the baffles.

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

They have to, and there is usually a hole through the baffles at the
lowest point of each baffle.

Have to what?

Capt. Bill

Have to have tunnels between the baffles.

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

They have to, and there is usually a hole through the baffles at the
lowest point of each baffle.

Have to what?

Capt. Bill

Yes, but it is better than nothing.

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

No offense -- but have you?

Yes.

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

No I didn't.

The plate bottoms, in particular, usually have tunnels.

That's my point. It takes much more aggressive agitation than "bubbling"
in one
baffled area to get the fuel stirred up and moving through your "tunnels".

Capt. Bill

Yes, but it is better than nothing.

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

No offense -- but have you?

Yes.

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

No I didn't.

The plate bottoms, in particular, usually have tunnels.

That's my point. It takes much more aggressive agitation than "bubbling"
in one
baffled area to get the fuel stirred up and moving through your "tunnels".

Capt. Bill

I gave up on "primary" and "secondary" to describe filters... I use
"initial" and "final" to describe mine. Oh yea, there's the polishing F-1
filter that works great!

"Doug Dotson" wrote in message
...
But the reality is that these things do work. There is tons of
annecdotal evedence. Please explain to me how it is that after
hours of polishing, the TP element is black with gunk and the
2uM Raycor following it still relatively clean. I really don't need
all these specs to allow me to believe what I can see with my own
eyes. Plus having the 2 uM Raycor at the end gives me a safety net
in case any of the little bugger sneak around the TP. Then another
couple filters (Raycor + engine filter) further protect the engine.

Is the filter on the engine the Primary or Secondary. DIfferent folks
seem to use different terminology.

Doug
s/v Callista

"Rich Hampel" wrote in message
...
Thats entirely untrue (Im being 'kind' here)

If you generate a bacterial slime/gel, that slime will 'de-polarize'
and block the flow based on surface area. Just compare the surface of
an open spaced (pleats not toughing together) pleated filter versus the
surface area of a cylindrical paper roll.

Also show me ANY data that you have on removal capacity on a per weight
basis vs. particle retention for a "roll of paper" filter.
You can of course document to an industry wide standard OSU F-2 test
stand test regime ???? I think not.
Do you have any retention efficiencies versus face velocity or
gpm/psid??
Whats the wet-strength of a roll of Charmin? Bounty? What is thier
average retention rating?


If you cant, its just SNAKE-OIL.







In article , Keith
wrote:

You need to look at depth filtration for polishing vs. surface
filtration
like the Racors. They will clog up very fast if you have dirty fuel.
See
the
link I posted earlier, and take a look at depth filters like the GCF
F-1
or
Jr.

"Doug Dotson" wrote in message
...
I don't have a filter problem, I have a pump question.

Doug

"Lew Hodgett" wrote in message
hlink.net...

"Doug Dotson" writes:
I am designing a fuel polishing and transfer system. My thought
is to use valves to route fuel from any tank to any tank. No
problem with that part. I want to be able to just transfer fuel
or switch in a filter to polish the fuel while transferring.
Since
I can select the same tank for source and destination, I can
polish fuel in place as well. The problem comes with the
selection
of a pump. I was looking at a Groco or Jabsco pump which seems
good for transfer purposes, but way exceeds the flowrate of the
filter when polishing. A Walbro fuel pump (which I have as a
priming
pump now) seems like a good fit for polishing (33 GPH) but will
be
slow
when just transferring fuel. What happens when a 5.5 GPM pump
(Jabsco) is pushing fuel through a filter rated at 60 GPH (RACOR
500)?

Have built the system above which BTW, uses a lot of 1/2" bronze
ball
valves.

You solve the filter problem in a straight forward fashion.

Multiple filters (Larger than 500) in parallel to reach at least
60
GPH.

I'd built in a safety margin and shoot for at least 75 GPH.

HTH


--
Lew

S/A: Challenge, The Bullet Proof Boat, (Under Construction in the
Southland)
Visit: http://home.earthlink.net/~lewhodgett for Pictures

I gave up on "primary" and "secondary" to describe filters... I use
"initial" and "final" to describe mine. Oh yea, there's the polishing F-1
filter that works great!

"Doug Dotson" wrote in message
...
But the reality is that these things do work. There is tons of
annecdotal evedence. Please explain to me how it is that after
hours of polishing, the TP element is black with gunk and the
2uM Raycor following it still relatively clean. I really don't need
all these specs to allow me to believe what I can see with my own
eyes. Plus having the 2 uM Raycor at the end gives me a safety net
in case any of the little bugger sneak around the TP. Then another
couple filters (Raycor + engine filter) further protect the engine.

Is the filter on the engine the Primary or Secondary. DIfferent folks
seem to use different terminology.

Doug
s/v Callista

"Rich Hampel" wrote in message
...
Thats entirely untrue (Im being 'kind' here)

If you generate a bacterial slime/gel, that slime will 'de-polarize'
and block the flow based on surface area. Just compare the surface of
an open spaced (pleats not toughing together) pleated filter versus the
surface area of a cylindrical paper roll.

Also show me ANY data that you have on removal capacity on a per weight
basis vs. particle retention for a "roll of paper" filter.
You can of course document to an industry wide standard OSU F-2 test
stand test regime ???? I think not.
Do you have any retention efficiencies versus face velocity or
gpm/psid??
Whats the wet-strength of a roll of Charmin? Bounty? What is thier
average retention rating?


If you cant, its just SNAKE-OIL.







In article , Keith
wrote:

You need to look at depth filtration for polishing vs. surface
filtration
like the Racors. They will clog up very fast if you have dirty fuel.
See
the
link I posted earlier, and take a look at depth filters like the GCF
F-1
or
Jr.

"Doug Dotson" wrote in message
...
I don't have a filter problem, I have a pump question.

Doug

"Lew Hodgett" wrote in message
hlink.net...

"Doug Dotson" writes:
I am designing a fuel polishing and transfer system. My thought
is to use valves to route fuel from any tank to any tank. No
problem with that part. I want to be able to just transfer fuel
or switch in a filter to polish the fuel while transferring.
Since
I can select the same tank for source and destination, I can
polish fuel in place as well. The problem comes with the
selection
of a pump. I was looking at a Groco or Jabsco pump which seems
good for transfer purposes, but way exceeds the flowrate of the
filter when polishing. A Walbro fuel pump (which I have as a
priming
pump now) seems like a good fit for polishing (33 GPH) but will
be
slow
when just transferring fuel. What happens when a 5.5 GPM pump
(Jabsco) is pushing fuel through a filter rated at 60 GPH (RACOR
500)?

Have built the system above which BTW, uses a lot of 1/2" bronze
ball
valves.

You solve the filter problem in a straight forward fashion.

Multiple filters (Larger than 500) in parallel to reach at least
60
GPH.

I'd built in a safety margin and shoot for at least 75 GPH.

HTH


--
Lew

S/A: Challenge, The Bullet Proof Boat, (Under Construction in the
Southland)
Visit: http://home.earthlink.net/~lewhodgett for Pictures

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/