Does anyone know what vacuum should be for my '84 300sd? When I unscrew the main line at the pump i get 3in idling and about 15 when I rev it up, also should it hold vacuum after you shut it off? It also wont shut off with the key,but the locking system still works. Where can I get info on the vacuum system, thanks Mike

You need over 20 for the Brake Booster to function properly.
I PMed you some info. look in the, Brakes Pneumatic section.

One of our members must have a write up on it:
DIY Repair Links
http://www.peachparts.com/shopforum/diy-links-parts-category/

http://www.peachparts.com/Wikka/DoItYourSelf

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84 300D, 82 Volvo 244Gl Diesel

Also, the locking system in your 300SD has a separate pump, which is located in the trunk, and operates electrically. It does not connect anywhere to the front engine operated pump.

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[/SIGPIC]~cirrusman

1983 Mercedes Benz 300SD - Wife calls him "Chitty Chitty Bang Bang"
[SIGPIC]




1983 Toyota Tercel (Tommy, The little Toyota that could)
1965 Ford F100 (Grandma Ford)
2005 Toyota Sienna (Elsa, Wife's ride)


Gone:
1988 Toyota Pickup
2004 Subaru Outback

1987 Cadillac Fleetwood Brougham
1986 Volvo 740 GL Station Wagon - Piece of junk.
1981 Volvo 242 DL 2 Door - Hated to see it go. R.I.P.
1987 Pontiac Fiero GT

Regarding holding vacuum after shutoff, there should be a vacuum reservoir in the rear which will store vacuum to operate door locks, etc after shutdown. It looks similar to an egg carton.

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84 300td (Yes, a wagon)
"The Golden Dragon"
195k, 2nd owner
Lives in Redmond, WA

Not on an SD. See post #3.

Oops, disregard

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84 300td (Yes, a wagon)
"The Golden Dragon"
195k, 2nd owner
Lives in Redmond, WA