When I bought my '71 Westy, the brake booster was disconnected, the most
obvious reason for which was that the rebuilt bug motor that was installed
didn't have a spot on the manifold to plug the hose into.  I replaced the
manifold awhile back, and have the one-way valve and the correct vacuum hose.
This weekend I went to hook things back up.  The Bentley doesn't have a great
deal of info/pictures so I thought I'd ask the list for advice.

First off, there are connectors on both sides of the booster.  It looks like
the hose from the engine goes to the one on the rear.  The connector on the
front seems to go to a hose that disappears into the frame or body.  I'm
assuming that this is just a means of equalizing pressure on the diaphragm?
Does anyone know which connector the engine goes to, and what the other
connector is for?

Anyway, before I ran the hose up front, I connected it to what I believe is
the correct connector (rear) on the booster and blew through it.  Sure enough,
it didn't hold pressure.  I tried to determine where the air was going,
figuring if the diaphragm was ruptured it would be going out the front
connector.  But I didn't feel any air coming out there.  In fact, it seems to
be coming out from where the master cylinder bolts on.  The Bentley shows an
O-ring at that location, so could that be the cause if the O-ring were
missing?  Or maybe the wrong MC entirely?  The PO had messed with the brakes
(among a host of other things) so it's not inconceivable.  Anyway, any
guidelines on the booster would be appreciated.

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