derek@best.com (Derek Au) writes:
>And maybe someone could help me out here, I'm going to retro-fit the brake 
>booster servo and master cylinder from a '71 vintage vanagon.  I've already 
>purchased the servo (yow! that was expensive!) the master cylinder and 
>vacuum line check valve.  I figure I'll have to fabricate and mig weld a 
>special bracket to mount the booster/master cylinder assembly and then run a 
>vacuum line to the engine compartment.  I plan to use copper tubing, cause 
>it does'nt rust and is available!  I have a question though, does anyone 
>know why there seems to a second vacuum line connection on the brake 
>booster, right where the operating rod from the brake pedal goes into the 
>brake booster?  This is in addition to the vacuum connection thats on the 
>large round housing of the booster where vacuum is usually connected.
I have a '71 Westy and am trying to hook my booster up as well.  Since it
was disconnected when I bought it, I don't have much to go on other than the
various manuals (which aren't that clear).  I noticed the two connection
locations, too, and posted to the list but didn't get a response.  On mine,
it looks like the REAR one goes to the manifold, and the FRONT one had a
hose (disconnected) near it that disappeared into the frame (?!).  It's just
a guess, but maybe the front connector is a vent, to allow air in and out as
the diaphragm moves back and forth?  The hose might just be to keep water,
etc. from getting in.  (Incidently, when I hooked my new hose up to the REAR
connector and blew into it, there wasn't much resistance.  I thought the
diaphragm might be broken, but the air feels like it's coming out around
the master cylinder.  There's supposed to be an O-ring around the MC, so maybe
that's all.  Any ideas?  I decided to wait for Spring to take things apart.)

Pat Walsh, '71 Westy, walshp@ippdsgi3.nawc-ad-indy.navy.mil