Litton:

This is MUCH easier than high vac systems!

The only real PITA is finding the bad part.

The vac lines run under the cover along the door sills (inside).

Most likely, if you have a leak all the time, not just when locked or unlocked, the door switch or the yellow plastic line is bad.

I personally thing the vacuum locks are simpler and more elegant than electric. Much better than hydraulic door closers in the 600 grand, too!

MB used them in one form or another from the early 50's, I think, to the latest models with keyless entry, when they changed to "Chyrsler" stlye electric.

Peter

__________________
1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!