Those blue caps are notoriously unreliable. It's a good thing to carry a
spare.

There is a small metal pipe that goes around the engine bay on '86 and up
vans. That ring will help bleed out any air in the sytem, provided there is
not a fault somewhere, like a leaking head gasket. The bleed air goes into
the expansion tank. On page 19.13 in the Bentley is the layout of that
system!

John
On Jun 4, 2016 22:41, "Neil N" <musomuso@gmail.com> wrote:

Hi John
I guess I should've also noted the type of engine in the main body of my
email.
Sorry about that.

This is regarding a vanagon 2.1 WBX.

I was referring to the hose that connects the long metal pipe around engine
bay, to upper (5/8" ?) nipple on the expansion tank.

As far as I know, air bubbles are NOT flowing into this tank all the time.

Searching the archives, it seems the fault **may** lie at the blue cap at
that tank, which was replaced  during the cooling system rebuild.

Neil

Air bubbles were flowing from that hose in to the expansion tank

On Saturday, June 4, 2016, John Rodgers <jrodgers113@gmail.com> wrote:

> Neil, what engine!
>
> On a 2.1 WBX the only hose that should come from the top of that expansion
> tank is from the pressure cap to the overflow tank.
>

--
Neil n

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