I learned it from personal experience with all those variations.

There are only 2 outer diameters of pipe.
All the metal are the same, ~ 1 1/4"
All the plastic are the same, ~ 1 1/2"

The 82 metal pipes are different at the engine end only, afaik.

I don't know much about the early aircooled Vanagons. Since VW designed
the Vanagon for watercooled engines from the start I assume the tanks
are the same shape. Since diesels came out mid year in the 81 model
production surely they planned for it beforehand with things like the
fuel tank.

Mark

neil n wrote:
> My goodness. Where do you find this info?   ;)
>
> Ok. So maybe the 70mm fill hole opening tank was designed to work with
> the '82 diesel pipes and maybe they were a smaller OD.
>
> Neil.
>
>