Jim:
Disconnect the hose from the top of the vacuum pump, start the engine and put
your thumb over the pump outlet (inlet?).  If you feel suction, you probably
have a leak in the hose to the brake booster.  If no suction, the vacuum pump
is suspect.  From the pictures you have posted on the WetWesties site, it
appears you have the old diaphragm-type vacuum pump.  There are rebuild kits
available for these (frequently on eBay).

Since it appears you have a Rabbit/Jetta engine in there, you're noise problem
may be influenced by the air cleaner set up.  On a stock Vanagon diesel, the
air cleaner is plumbed to a snorkel that goes up the inside of the left rear
corner, sucking air through the vent on the side of the van.  Your pics look
like the air cleaner is just sucking air from atop the engine itself.  This
intake noise can contribute quite a bit to the overall engine noise.  Go to
your FLAPS and get some flexible air cleaner hose and route that intake
somewhere else.  Also, does your engine cover close completely with the
Rabbit/Jetta injection pump lever?  Check the seal around the cover and if you
have a bed cushion to put over the cover, do so.  This will help muffle the
noise.  However, noise is a problem with the Vanagon Diesel at 4500 rpm.

BTW - love the 'stinken name!

Maynard Southard  (OvO) '79
'86 Double Cab Diesel "Col. Potter"
'82 Westy Diesel "Reinhardt"
'82 Vanagon GL Diesel "Sluggo"
'93 EV GL "Klinger"
'00 Golf GLS TDI "WooHoo"
'84 Jetta GL TD "Donor"

On Thursday, August 08, 2002 8:08 PM, Jim Arnott <jrasite@eoni.com> wrote:
>Boy... it sure is noisy in here...

> Who can talk to me about Diesel vacuum pumps? I'm curious about the
> position (rotationally).  Does it affect anything other than fit? In
> other words, why no power to the brakes?