Makes sense, but there is quite alot of evidence out there that
a polishing system is a good thing to have. I can't really
increase the size of my on-engine filter. I could increase the
size of the Raycor, but at the pore sizes I run (30 micron) in it make it
necessary to change the on-engine filter regularly as well.
Bigger Raycor won't fix the problem.

Doug

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

Unfortunately that fuel clogs up the filters. That is the entire problem.
Having clean fuel in the engine fuel system avoids the problem.


Just go up a size or two in your filters. The surface area difference
between a
500 Racor and a 900 Racor is tremendous.
Many times on a boat with filter clogging problems, I have just installed
a
larger filter system and the time between changes has gone back to normal
with
no more clogging in heavy seas problems.

Capt. Bill

On Tue, 25 Nov 2003 17:49:20 -0500, "Doug Dotson"
wrote:

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)?

Thanks!
Doug
s/v Callista

Doug,

I just finished building a fuel polishing system for my boat, using a
Walbro pump. I had an old Fram filter (using a Wix element) and
purchased a new Racor. With the system I can change filters while the
engine is running. I can also monitor the filters with a vacuum gage
so I know in advance when a filter is getting clogged. I wanted a
pump that would pull fuel through the system faster than the Walbro so
that I could do more filtering in a set period of time. But beginning
with advice from contributors to this newsgroup and then researching
on my own, I found that the filters would not filter properly if the
fuel were pulled through faster.

So, unless you are willing to purchase very large (and expensive)
filters or several filters in parallel (also expensive), you will need
a pump like the Walbro for fuel polishing and a separate pump for fuel
transfer, if you want to transfer quickly. Also note that the Walbro
is specified for continuous operation while some other fuel tolerant
pumps are not. You need continuous operation for polishing.

To solve the question of only polishing clean fuel while the crud
remained on the bottom of the tank, I have a sealable opening in the
top of the tank and enough room to put in a long stick to stir the
fuel. My 100 gallon tank does not seem to have baffles that would
render this method less effective.

I would have installed a Gulf Coast filter (paper towels) instead of
the old Fram, but I could not afford one. They are damned expensive.
I have no personal knowledge nor objective research results that back
up their claims of superior filtering. I just accepted the hype.

BTW I saw a Walbro pump for sale on E-Bay two days after I purchased
mine, and for half the price I paid. The seller seemed to have
several available.

Lee Huddleston
s/v Truelove

On Tue, 25 Nov 2003 17:49:20 -0500, "Doug Dotson"
wrote:

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)?

Thanks!
Doug
s/v Callista

Doug,

I just finished building a fuel polishing system for my boat, using a
Walbro pump. I had an old Fram filter (using a Wix element) and
purchased a new Racor. With the system I can change filters while the
engine is running. I can also monitor the filters with a vacuum gage
so I know in advance when a filter is getting clogged. I wanted a
pump that would pull fuel through the system faster than the Walbro so
that I could do more filtering in a set period of time. But beginning
with advice from contributors to this newsgroup and then researching
on my own, I found that the filters would not filter properly if the
fuel were pulled through faster.

So, unless you are willing to purchase very large (and expensive)
filters or several filters in parallel (also expensive), you will need
a pump like the Walbro for fuel polishing and a separate pump for fuel
transfer, if you want to transfer quickly. Also note that the Walbro
is specified for continuous operation while some other fuel tolerant
pumps are not. You need continuous operation for polishing.

To solve the question of only polishing clean fuel while the crud
remained on the bottom of the tank, I have a sealable opening in the
top of the tank and enough room to put in a long stick to stir the
fuel. My 100 gallon tank does not seem to have baffles that would
render this method less effective.

I would have installed a Gulf Coast filter (paper towels) instead of
the old Fram, but I could not afford one. They are damned expensive.
I have no personal knowledge nor objective research results that back
up their claims of superior filtering. I just accepted the hype.

BTW I saw a Walbro pump for sale on E-Bay two days after I purchased
mine, and for half the price I paid. The seller seemed to have
several available.

Lee Huddleston
s/v Truelove

"Doug Dotson" wrote in message
...
I am designing a fuel polishing and transfer system. My thought

[snip]

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)?

Probably nothing much will happen to the filter - as you increase the flow
through the filter, the resistance increases. The increased resistance
reduces the output of the pump (5.5 GPM is probably with no resistance). At
some point you'll reach an equilibrium condition where the increased
resistance of the filter meets the fuel pump's output curve.

You could talk to Racor (now owned by Parker I think) about exceeding the
rated flow rates and see if they have a contrary opinion. Perhaps the
filtering action is impeeded by the higher flow rate. You could also
install a gate valve in the system to throttle the pump output. You could
check the pump output by pumping into a temporary container and measuring
the output.

Whatever brand of pump you get, make sure it is rated for pumping fuel.

--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

"Doug Dotson" wrote in message
...
I am designing a fuel polishing and transfer system. My thought

[snip]

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)?

Probably nothing much will happen to the filter - as you increase the flow
through the filter, the resistance increases. The increased resistance
reduces the output of the pump (5.5 GPM is probably with no resistance). At
some point you'll reach an equilibrium condition where the increased
resistance of the filter meets the fuel pump's output curve.

You could talk to Racor (now owned by Parker I think) about exceeding the
rated flow rates and see if they have a contrary opinion. Perhaps the
filtering action is impeeded by the higher flow rate. You could also
install a gate valve in the system to throttle the pump output. You could
check the pump output by pumping into a temporary container and measuring
the output.

Whatever brand of pump you get, make sure it is rated for pumping fuel.

--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

Are you guys sure you really need all this stuff?

I fueled in some pretty suspicious places with questionable fuel in a lot of
third world countries. I used a Baja filter for all the fuel entering the 1
(one) and only fuel tank. It would usually pick up a few ounces of water
and a lot of crud in the first filter element.

The one and only time bad fuel stopped our engine was in the ICW after
picking up a load of very water logged fuel. Just anchored, changed the
filter, and emptied about 1 quart water from the filter bowl. Because I was
in the US, where bad fuel is seldom a problem, I didn't use the Baja
filter....I must have been that guy's only customer that year.

Just my experience after 3-1/2 years cruising.


--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

Are you guys sure you really need all this stuff?

I fueled in some pretty suspicious places with questionable fuel in a lot of
third world countries. I used a Baja filter for all the fuel entering the 1
(one) and only fuel tank. It would usually pick up a few ounces of water
and a lot of crud in the first filter element.

The one and only time bad fuel stopped our engine was in the ICW after
picking up a load of very water logged fuel. Just anchored, changed the
filter, and emptied about 1 quart water from the filter bowl. Because I was
in the US, where bad fuel is seldom a problem, I didn't use the Baja
filter....I must have been that guy's only customer that year.

Just my experience after 3-1/2 years cruising.


--
Evan Gatehouse

you'll have to rewrite my email address to get to me
ceilydh AT 3web dot net
(fools the spammers)

Well fellow asshole, I got a pair of circumnav's - what lake you
learning in.


On Wed, 26 Nov 2003 05:39:34 -0600, "Keith"
wrote:

Ever think about running a polishing system while underway, or right after
you come back from a "rolly bouncy" trip? Opinions are just like assholes...
everybody's got one.

"jlp2550" wrote in message
.. .
This is so true it isn't funny - but these marina sailors don't know
that - so they invent these stupid designs - like the guy with 6 or 8
or 12 fuel tanks in a 50' boat - what total stupidity. Get a life - go
cruising - instead of being "wanna-be" naval architects.

LISTEN UP - all the **** sits on the bottom till the 1st rolly bouncy
storm - then it gets stirred into suspension - and sucked into the
filters and clogs them quickly.

BTW, throw away your epirbs and radios so you can't call someone out
into danger to rescue your stupid ass.




And fuel "polishing" is a joke IMHO.
Unless the fuel in the tank/s is well stirred up all you are doing is
filtering
what is already clean, settled out fuel.

Capt. Bill

Well fellow asshole, I got a pair of circumnav's - what lake you
learning in.


On Wed, 26 Nov 2003 05:39:34 -0600, "Keith"
wrote:

Ever think about running a polishing system while underway, or right after
you come back from a "rolly bouncy" trip? Opinions are just like assholes...
everybody's got one.

"jlp2550" wrote in message
.. .
This is so true it isn't funny - but these marina sailors don't know
that - so they invent these stupid designs - like the guy with 6 or 8
or 12 fuel tanks in a 50' boat - what total stupidity. Get a life - go
cruising - instead of being "wanna-be" naval architects.

LISTEN UP - all the **** sits on the bottom till the 1st rolly bouncy
storm - then it gets stirred into suspension - and sucked into the
filters and clogs them quickly.

BTW, throw away your epirbs and radios so you can't call someone out
into danger to rescue your stupid ass.




And fuel "polishing" is a joke IMHO.
Unless the fuel in the tank/s is well stirred up all you are doing is
filtering
what is already clean, settled out fuel.

Capt. Bill

Doug-
RCI Fuel Purifiers have capacities from 1.5 to 400 gpm...they have no moving
parts and no element to change. The purification is done with baffle and
coalescer plates. These purifiers remove particulate down to less than 10
microns and 99.9% of water. Their website is: http://www.rcipurifier.com/

In all honesty, I am associated with this company (and with Gulf Coast
Filters) and I manufacture onboard fuel polishers.


--
Charlie Johnson
JTB Marine Service
St. Petersburg, FL
727.560.9065



"Doug Dotson" wrote in message
...
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)?

Thanks!
Doug
s/v Callista