> Mine has the plastic filter before the fuel pump (large output line) AND
> the metal one after.  Was that done at the factory or by a previous
> owner?

I have seen many '86-89 vintage Vanagons with this configuration, enough to
make me suspect that at least some were equipped that way by the factory (or
perhaps by the dealer during a warranty service interval).  The percentage
I've seen is too high for me to believe that they all happened to have been
modified that way by a previous owner.

> And is it necessary?

Perhaps not, but I have yet to hear of it having a drawback or causing any
fuel starvation problems.  On the other hand in a severe case it could
protect the fuel pump if there were a lot of crud in the tank.  So it seems
to me it is far more likely to prevent a problem than to cause one.
Therefore, while I can't say I'd run out and put a filter there if my
Vanagon didn't come with it, I also wouldn't be the least bit hesitant to.

> This change was might also coincide with the chance in engine size.  The
tank
> needed to provide more fuel to the larger engine.

No, the change occurred several years after the change in engine size.  And
it didn't occur at all in many countries.

- Ron Salmon
  The Bus Depot, Inc.
  www.busdepot.com
  (215) 234-VWVW