Date:         Mon, 16 Jul 2001 10:12:00 -0700
Reply-To:     Jim Arnott <jrasite@EONI.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Jim Arnott <jrasite@EONI.COM>
Organization: WetWesties <http://wetwesties.org>
Subject:      Re: Placement of Fuel Filter
Content-Type: text/plain; charset=us-ascii

Here's my OPINION on fuel filter placement:

Filter before pump - nice clean fuel through the entire system. Until
filter plugs.  Then no fuel going to pump.  Pump is cooled by the fuel.
Pump overheats and fails... It's also a rotary style pump and is
relatively unaffected by small particles. Fuel filter has only gravity
feed so does not have to withstand high pressures. Cheap. Electric fuel
pumps also push much better than pull.

Filter after pump - dirty fuel possibly through pump.  Not a big deal as
long as the particles are small.  Such particles are abrasive though and
will wear the pump over time.  Filter clogs and the pump is still cooled
by the fuel from the tank. Requires a larger, stronger (read: more
expensive) filter.

Filter before and after pump - (BTW, not stock set-up) possibly best if
the pre-pump filter has a large enough 'screen size' to prevent
clogging.

I'm reminded of Chas. (Boss) Kettering's comment that, "Parts left out
cost nothing and have an infinite service life."

VW saw fit to install one filter and specify its replacement at certain
intervals.  I'd be inclined to replace it at those intervals and leave
it at that.

Jim Arnott ("Hey group, why does my bus fall flat on its face at 3k
rpm?" Answer? Bad fuel filter - that took the pump with it. Live and learn...)