Fuel Polishing
Fuel Polishing System
Mounted for easy installation
I have assembled a fuel polishing system consisting of two Racor
500 FG filters, a 7 psi Walbro fuel pump, 4 three way valves, a vacum
gauge, and assorted fittings and hose onto a plywood board.  

Once assembled, I can install mounted system in the boat and hook
up the connections to the fuel tank, to the engine, from the engine,
and the return.  I will be using Parker Push Fit fittings for all the

I got the idea of using the Parker Push Fit fittings from Pete Dubler
Regina Oceani   I also got the design off the internet...at a chat
board for trawlers I believe...
Fuel Polishing System Plumbing
Layout...The person who designed it is named Bill Bickley.  I liked
the design and it fit my limited budget, space, and needs.

See below for the drawings that Bill Bickley developed.......
Normal Operation:

The fuel system runs through the primary
Racor filter and to the engine as it did
before....only now the feed line goes into
a three-way valve.  In normal operation, it
will go to  the primary filter and out to
another three-way valve...which will
normally be set to feed the engine.  The
engine return runs into another three-way
valve and will normally be directed back
to the tank.

Marked in green tape seen below....
Back up Operation:

In the event the primary becomes
inoperable, I can switch to have the fuel run
through the polishing filter.  This will require
me turn the first three-way (marked with
blue tape).  It will run throught the polishing
filter and through the Walbro pump.  This
will come into another three-way valve and
will require be to turn the three-way valve
that feeds the engine to blue.

Marked in blue tape seen below....
Polish Operation:

To run on polish....I have the valve settings
the same as on back-up and just change
the return three-way valve to bypass the
engine.  I turn on the Walbro pump and now
can filter the tank through a 30 micron
Racor filter

Marked in yellow tape seen below....
Connection to existing lines:

I am planning on connectig to the existing copper fittings using some adapters that will fit the exsisting
copper flare-nuts.  I will then run hose back to my fuel polishing set up.

The fittings can be seen below....