<<<That water pump is on the eurovans and several audi and mercedes as
well. The mercedes I worked on had the pump connected with the cooling
fan to circulate water when the car is stopped. I believe it is hooked
up the same way on the eurovans.
jimt>>>

Prior to taking a ride over to VW to check this out, where is this pump
mounted?

Is it a rotary in line set up or what kind of pump?

This auxiliary pump would have to be larger in diameter than the hose.

Now, what is the ID of the connection area of this pump?

If it's 1.25", it would work only on the earlier Vans.

1.50" would work on only the later model's.

If's going to be mounted up front above the spare tire well, I hope that
it's small enough in diameter to clear the spare.

It's hooked up with the fan to kick on when the engine gets hot, or???

I could see a by pass switch mounted under the dash for a long pull or
high end run in this heat.

It could (?) ( might ) help move some coolant back to the engine or up
to the radiator.

But the radiator could only handle just so much fluid in any given time,
so pushing the fluid too fast would be self defeating.

And then we have the old flabby hose treatment.

This pump would kick on, raise the pressure of the fluid, because the
old plugged up radiator couldn't handle the increased volume, and the
old hoses would start blowing.

Interesting concept.

A larger 3 or 4 core radiator would get you to the same end result.
IF you could shoe horn it into the front end ( which isn't going to
happen )