Eric,  I have been looking for missing break fluid for my reservoir too.
My break pedal is firm but the clutch pedal is not after the reservoir is
too low. If I press on the pedal several times with the engine off to
exhaust vacuum in the system, then depress the pedal with medium pressure
and hold while starting the engine.  If the break booster is working
properly, pedal will fall slightly and then hold.(This is how the Bentley
says to check the break booster pg 47.10).  Could my booster be operating
properly if fluid is leaking into it as with your situation?  Thanks Jeff

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> From: Eric Henning <eric.henning@US.ABB.COM>
> To: vanagon@GERRY.VANAGON.COM
> Subject: Dem's da brakes!
> Date: Wednesday, February 02, 2000 7:01 AM
>
> Well after bragging how well my 80 westy has been running, the  VW fairy
decided
> I needed a little humble pie.  My westy still runs great, the problem is
> stopping.  On the drive home from work yesterday, I thought I heard a
little
> pop!, then when I went to stop my brake pedal was very soft.  This past
summer I
> re-built all the brakes including hoses.  I made it home the short
distance,
> then hopped out and found absolutely no fluid leaking! yet I was down a
pint.
> Some of you know where I am going.  I took the vacuum line off the brake
booster
> and stuck my Mighty-Vac brake bleeder hose into the booster.  I then
proceeded
> to suck 1 pint of brake fluid out of the booster. I am pretty sure this
is not
> normal.  So, I will be checking vendors, but if anybody has a good used
booster
> for sale (all vanagon boosters the same), I'd like to hear from you.
>
> eric.henning@us.abb.com
> 80 westy