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Lee,
<BR> Parallel filters are standard on larger commercial diesels.
I served as chief engineer for a time on the 125 ft schooner <I>Alexandria</I>
and as mate on one of the <I>Spirit</I> dinner cruise boats and had a chance
to see how they worked. I will sketch something and mail it to you as I
don't think I can e-mail it.
<P> Some of the larger boats, with multiple tanks, have
very complex tankage & plumbing, manual and power pumps, etc. They
usually can transfer fuel to balance the ship and/or access clean fuel
in case one tank gets contaminated with dirt or sea water. The idea with
the parallel filters is 1) to have a backup in case #1 clogs and 2) to
be able to clean a dirty filter while the engines get fuel through the
other. We did that routinely aboard the <I>Alexandria.</I>
<BR> After a near-disaster with my own boat when sediment
stirred up by heavy weather got into the screen inside the tank (Very bad
idea, that screen), I put on the parallel Racors and the auxiliary tank.
It was not all that hard, nor expensive. Certainly no more than the cost
of the damage and the tow!
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- Gordon</HTML>