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

Have any idea what
might
have been used to bed the inspection ports?

The ones I have dealt with have had gaskets on them. If yours don't I would
look into making some and/or using a fuel resistant sealant.
http://www.watkins-associates.com/index.html
Capt. Bill

I won't be able to tell for sure until I open one up. Just looking
at them from the outside it appears they are bedded in something
black. The outside surface of the tanks are not smooth. If the
inside is not smooth as well that would explain why they were
bedded rather than gasketted. I think what I may do is have
some inspection ports fabricated that can be opened more
easily.

Doug
s/v Callista

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

Have any idea what
might
have been used to bed the inspection ports?

The ones I have dealt with have had gaskets on them. If yours don't I
would
look into making some and/or using a fuel resistant sealant.
http://www.watkins-associates.com/index.html
Capt. Bill

I won't be able to tell for sure until I open one up. Just looking
at them from the outside it appears they are bedded in something
black. The outside surface of the tanks are not smooth. If the
inside is not smooth as well that would explain why they were
bedded rather than gasketted. I think what I may do is have
some inspection ports fabricated that can be opened more
easily.

Doug
s/v Callista

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

Have any idea what
might
have been used to bed the inspection ports?

The ones I have dealt with have had gaskets on them. If yours don't I
would
look into making some and/or using a fuel resistant sealant.
http://www.watkins-associates.com/index.html
Capt. Bill

Since this has gone on and on, may I restate and expand on my original
comment.

First step is to pump off whatever water and crap is on bottom of tank --
this from a pickup hose shoved to tank bottom or using a bottom drain cock
which are seldom seen..

Second step is to, while polishing, agitate fuel at bottom of tank using a
small L-shaped air discharge pushed down to tank bottom on a rod or dowel
and turned about as much as possible. Obviously the fuel furthest away from
the discharge will get the least agitation and baffles will reduce degree of
agitation for sure. But with the L-shaped discharge at the bottom and
turned, disturbance will flow through baffle bottom notches. The basic idea
is to get crud in suspension and moving so it can be captured by the
polishing pick up and filtered out.

It's not a perfect system and won't take the place of physically cleaning an
empy tank. But it seldom fails to be good enough for all practical purposes
for a majority of pleasure boats, probably with tanks up to 150 gallons. Can
last for years on active vessels. Or just until you get your next load of
crappy fuel.


Eliminate "ns" for email address.
"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

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.

Yes, but only if the fuel is well shaken, not "bubbled" in one baffle. And
that's the context that my answer was written in.

I assumed that was understood. :-)

Capt. Bill

Since this has gone on and on, may I restate and expand on my original
comment.

First step is to pump off whatever water and crap is on bottom of tank --
this from a pickup hose shoved to tank bottom or using a bottom drain cock
which are seldom seen..

Second step is to, while polishing, agitate fuel at bottom of tank using a
small L-shaped air discharge pushed down to tank bottom on a rod or dowel
and turned about as much as possible. Obviously the fuel furthest away from
the discharge will get the least agitation and baffles will reduce degree of
agitation for sure. But with the L-shaped discharge at the bottom and
turned, disturbance will flow through baffle bottom notches. The basic idea
is to get crud in suspension and moving so it can be captured by the
polishing pick up and filtered out.

It's not a perfect system and won't take the place of physically cleaning an
empy tank. But it seldom fails to be good enough for all practical purposes
for a majority of pleasure boats, probably with tanks up to 150 gallons. Can
last for years on active vessels. Or just until you get your next load of
crappy fuel.


Eliminate "ns" for email address.
"LaBomba182" wrote in message
...
Subject: Fuel transfer/polishing pump
From: "Doug Dotson"

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.

Yes, but only if the fuel is well shaken, not "bubbled" in one baffle. And
that's the context that my answer was written in.

I assumed that was understood. :-)

Capt. Bill

After doing a bit more research, I'm starting to wonder what the
big attraction to the TP filters is. A standard filter cartridge housing
in stainless steel can be had for $40 to $80 cheaper than the TP
housing. Filter cartridges start at $3. Also, by using a standard
filter cartridge holder you have the flexibility of changing filter
cartridge types if necessary.

Doug
s/v Callista

"Rich Hampel" wrote in message
...
Please appreciate that I dont want to appear to be an arrogant
know-it-all after being in on and aroud critical filtration/separation
most of mworking life ... and yet give just enough information that
each can take and arrive a result that is based on current or
state-of-the-art results.

ANY filter media (including compressed pubic hair) thats used in a
recirculation polishing system will work ... its all a matter of
degree. Whats wrong with TP, etc. is that the material used to filter
is not bonded, can digest (make more particles) in the presence of
water --- thus to do the exact opposite of what you are trying to do.
If doesnt matter if rust, bacteria or broken up toilet paper fibers
blocks the final filter to your engine... expecially during an
emergency. Unbonded cellulose is notorious for unloading particles or
allowing the particles to migrate through the filter .... OK if the
main system is not drawing fuel thats OK as the recirculating slurry
will probably be recaptured; but, if all hell breaks loose and you have
a high fuel demand at the time when the TP decides to unload itself or
its already trapped debris .... the whole system can catastrophically
fail ....

My objection to TP - very poor efficiency, migrates particles, migrates
fibers, unloads at increasing differential pressure, larger first cost
due to need for larger diameter housing, no constancy of retention,
knife edge seals of 'cartridge' - very limited in retention and VERY
prone to bypass. Short life due to low surface area. TP will '
deform' - wrinkle into a smaller mass when heavily laden and
differential pressure is high (remember those knife edge seals) then
unload and bypass.

As far as experience ..... the high tech/high purity industry used such
devices for many years: loose fiberglass, Kotex pads, string wound
cylinders, TP, chopped cellulose ....... until after WWII the world
started using captured German technology: membranes, cartridges, etc.
If TP were any good, industry would still be using it. The last such
system I personally replaced/upgraded was in the mid 70s. ..... as a
cost cutting measure!!!!!

DO NOT depend on filters to remove the crud in your system. If they
plug it means that you are contaminated and need to clean your fuel
system. Such plugging clearly indicates a **symptom**, the filters
prevented the symptom from becoming an extremis situation. If your
system is plugging filters, they did do their job as they are supposed
to .... but now go back in and clean the system! Resident particles
form and agglomerate into more particles. Bacterial scums feed other
bacteria, etc. Your symptoms of plugging filters means your system is
contaminated.... a filtration system is a band-aid or a 'condom' to
prevent stoppage. Consider to thoroughly mechanically CLEAN the tank.


;-)

In article , Steven Shelikoff
wrote:

Rich,

I appreciate that you seem to be an expert on filtering theory even
though you also seem to lack the practical experience of actually using
the TP or PT depth filters we're talking about. I realize you don't
think they work. Even so, I'd love to hear your expert opinion
(absolutely no sarcasm intened) on why my Racor 2uM filter has lasted so
long (2 years now and still not clogged) after installing a TP prefilter
when I completely clogged two of the same filters in 20 minutes each
before installing the TP prefilter.

Steve

After doing a bit more research, I'm starting to wonder what the
big attraction to the TP filters is. A standard filter cartridge housing
in stainless steel can be had for $40 to $80 cheaper than the TP
housing. Filter cartridges start at $3. Also, by using a standard
filter cartridge holder you have the flexibility of changing filter
cartridge types if necessary.

Doug
s/v Callista

"Rich Hampel" wrote in message
...
Please appreciate that I dont want to appear to be an arrogant
know-it-all after being in on and aroud critical filtration/separation
most of mworking life ... and yet give just enough information that
each can take and arrive a result that is based on current or
state-of-the-art results.

ANY filter media (including compressed pubic hair) thats used in a
recirculation polishing system will work ... its all a matter of
degree. Whats wrong with TP, etc. is that the material used to filter
is not bonded, can digest (make more particles) in the presence of
water --- thus to do the exact opposite of what you are trying to do.
If doesnt matter if rust, bacteria or broken up toilet paper fibers
blocks the final filter to your engine... expecially during an
emergency. Unbonded cellulose is notorious for unloading particles or
allowing the particles to migrate through the filter .... OK if the
main system is not drawing fuel thats OK as the recirculating slurry
will probably be recaptured; but, if all hell breaks loose and you have
a high fuel demand at the time when the TP decides to unload itself or
its already trapped debris .... the whole system can catastrophically
fail ....

My objection to TP - very poor efficiency, migrates particles, migrates
fibers, unloads at increasing differential pressure, larger first cost
due to need for larger diameter housing, no constancy of retention,
knife edge seals of 'cartridge' - very limited in retention and VERY
prone to bypass. Short life due to low surface area. TP will '
deform' - wrinkle into a smaller mass when heavily laden and
differential pressure is high (remember those knife edge seals) then
unload and bypass.

As far as experience ..... the high tech/high purity industry used such
devices for many years: loose fiberglass, Kotex pads, string wound
cylinders, TP, chopped cellulose ....... until after WWII the world
started using captured German technology: membranes, cartridges, etc.
If TP were any good, industry would still be using it. The last such
system I personally replaced/upgraded was in the mid 70s. ..... as a
cost cutting measure!!!!!

DO NOT depend on filters to remove the crud in your system. If they
plug it means that you are contaminated and need to clean your fuel
system. Such plugging clearly indicates a **symptom**, the filters
prevented the symptom from becoming an extremis situation. If your
system is plugging filters, they did do their job as they are supposed
to .... but now go back in and clean the system! Resident particles
form and agglomerate into more particles. Bacterial scums feed other
bacteria, etc. Your symptoms of plugging filters means your system is
contaminated.... a filtration system is a band-aid or a 'condom' to
prevent stoppage. Consider to thoroughly mechanically CLEAN the tank.


;-)

In article , Steven Shelikoff
wrote:

Rich,

I appreciate that you seem to be an expert on filtering theory even
though you also seem to lack the practical experience of actually using
the TP or PT depth filters we're talking about. I realize you don't
think they work. Even so, I'd love to hear your expert opinion
(absolutely no sarcasm intened) on why my Racor 2uM filter has lasted so
long (2 years now and still not clogged) after installing a TP prefilter
when I completely clogged two of the same filters in 20 minutes each
before installing the TP prefilter.

Steve

On Sat, 6 Dec 2003 22:09:44 -0500, "Doug Dotson" wrote:

After doing a bit more research, I'm starting to wonder what the
big attraction to the TP filters is. A standard filter cartridge housing
in stainless steel can be had for $40 to $80 cheaper than the TP
housing. Filter cartridges start at $3. Also, by using a standard
filter cartridge holder you have the flexibility of changing filter
cartridge types if necessary.

I got a good deal on my TP cartridges. 2 for the price of 1 and that 1
was also discounted. If I had to pay full price for them I might have
looked elsewhere also. But I still think they're a good deal if you
have a really messy tank to clean up because the elements are so cheap.

Steve

On Sat, 6 Dec 2003 22:09:44 -0500, "Doug Dotson" wrote:

After doing a bit more research, I'm starting to wonder what the
big attraction to the TP filters is. A standard filter cartridge housing
in stainless steel can be had for $40 to $80 cheaper than the TP
housing. Filter cartridges start at $3. Also, by using a standard
filter cartridge holder you have the flexibility of changing filter
cartridge types if necessary.

I got a good deal on my TP cartridges. 2 for the price of 1 and that 1
was also discounted. If I had to pay full price for them I might have
looked elsewhere also. But I still think they're a good deal if you
have a really messy tank to clean up because the elements are so cheap.

Steve

In article , Len Krauss
wrote:


Second step is to, while polishing, agitate fuel at bottom of tank using a
small L-shaped air discharge pushed down to tank bottom on a rod or dowel
and turned about as much as possible. Obviously the fuel furthest away from
the discharge will get the least agitation and baffles will reduce degree of
agitation for sure. But with the L-shaped discharge at the bottom and
turned, disturbance will flow through baffle bottom notches. The basic idea
is to get crud in suspension and moving so it can be captured by the
polishing pick up and filtered out.


You are correct!!!! but dont use air.

Tank farms use whats known as a *sparging nozzle* to keep the tank in
constant agitation. Its simply a jet of liquid that discharges into a
throat of a venturi section. The velocity from the jet into the
venturi 'entrains' the liquid in the bottom of tank to circulate. A
sparger moves the layers on the bottom of the tank towards the top;
hence, affects a mixing.
(for techies amoung us, a sparging nozzle {sparger} in an 'open inlet
eductor')

If you use air, you generate a lot of air entrainment which can settle
out and coalesce into larger and larger bubbles of air .... and block
the downstream system.