Wix makes a lawn mower-looking metal fuel filter with 1/.2"x1/2" that
I've had success using as a prefilter. Don't have the part number in
front of me, but you can gothe back of the Wix catalogue and find a
picture of it with part number.

DM&FS

At 08:05 PM 5/16/2010, craig cowan wrote:
>You are correct in assuming that your van was designed not to use that
>filter. The outlet on your tank is going to be 11mm, while the outlet on
>'80-'84 vans is 7mm. Thus, these earlier vans require the prefilter to adapt
>the size from the 7mm tank outlet to the 7mm input on the filter, then an
>11mm line from the large end of the filter to the input of the fuel pump.
>Then 7mm all after the fuel pump.
>
>Replacement tanks come with 11mm outlets.
>
>'85+ vans do not have the provisions for that prefilter without adapting the
>11mm line down to a 7mm before the filter. This often causes cavitation
>which results in a loud fuel pump, hence the reason why VW went to all 11mm
>line upstream of the filter.
>
>My suggestion would be either search for a different manufacturer of large
>particle prefilter with 11mm inputs and outputs, or just negate it. If your
>tank is full of crap, your tank needs to be cleaned.
>I just adapted my '85 to the '86+ style with the 11mm outlet on my new fuel
>tank, so I've been there and been confused.... you're just going in the
>opposite direction that I did.
>
>
>-Craig
>'85GL turned WESTY
>BOSTIG in the back
>
>On Sun, May 16, 2010 at 4:28 PM, Peter DiFalco <peter.difalco@gmail.com>wrote:
>
> > I'm resealing the tank on my 89 today ... and yesterday (everything takes
> > me
> > 4X longer than regular people)... and anyway I am trying to reverse VW's
> > bizarre decision to delete the large-particle pre-pump fuel filter (square
> > one) and add one. So I bought the correct filter (at least according to the
> > VW parts place) and I'm finding that the outlet on my fuel tank has a much
> > larger ID than the inlet on the fuel filter. The outlet on the filter is
> > actually larger, back up to the ID of the tank outlet, which matches the
> > inlet on the fuel pump.
> >
> > So... either my fuel tank was specifically designed with a larger outlet to
> > not use that filter and to plumb right to the fuel pump, or I bought the
> > wrong fuel filter, or there's something else missing I can't imagine what.
> > Please advise, oh wise list.
> >
> > I'm concerned that all my fuel tank manipulation and tilting and whatnot
> > have dislodged some of those larger particles and I'd rather not send them
> > through my fuel pump when I hook this sucker back up.
> >
> > One thing I'd thought of was picking up a PCV valve that has the two
> > different diameter ports on it, and throwing it inline to step down the
> > diameter prior to the filter. But I am not sure that randomly throwing
> > valves around is a super good idea.
> >
> > -Peter
> >