The "white box" is a fuel filter. Some Vanagons had only that filter,
some have just the larger post pump filter, some have both.

The "screen" I referred to is inside the pump inlet. Here's a close up
shot I took looking directly into the fuel pump inlet:

https://photos.app.goo.gl/N101uXq6fAPzstnk1

The white square filter should prevent debris from gathering at the
screen inside the fuel pump. ..... I'd think anyways.

The fuel pump can make noise due to fuel cavitation but the pump will
still operate ok in spite of that. There's several factors that can
cause fuel cavitation. One being restricted flow from the fuel tank.
There are fuel pressure and delivery rate tests shown in the Bentley
manual.

On 10/2/17, Cunegonde <cunegonde.van.westfalia@gmail.com> wrote:

> Since the car hasn't been towed home yet, I haven't gotten a chance to pull
> the post-pump filter outlet and see if there's output. But the pump doesn't
> sound quite right while it's still in the car.
>
> What "screen at fuel pump inlet" are you referring to? Is that the white box
> between the tank and the pump?
>

 .....

>> Be sure to check and clean the screen at fuel pump inlet.

--
Neil n

Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>

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1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>

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