G'mornin' Folks,

I'm working on the Vacuum System of my '85 300D-T. It appears that I have some sort of late version (or modification) of the "Change Over Valve".

My vehicle has a micro switch, in association with a cam plate located atop the valve cover. And a device that I believe to be the Change Over valve mounted on the Left (driver side) wheel well.

I have been through the MB Library on CD, A Vacuum Troubleshooting Guide (purchased on e-Bay), and to several parts sources including Phil's place that is associated with this forum....don't seem to be able to identify this fender well mounted vacuum do-dad......

Is anyone familiar with this particular setup??

I have no problems with any of my diesel maintenance, having been a ship's engineer. I also am quite familiar with vacuum, as steamships rely on it, big time. I have the MiteyVac setup.....just looking to identify and maintain this particular vacuum system.

Perhaps I have missed it, but a Fluidic (I think that this is the correct terminology for the vacuum logic) Flow Chart would be very helpful to me. Sort of "if - then" diagram.....turn ignition key off, moves valve on ignition switch, allowing vacuum to the Injection Pump shutdown device......sort of a what operates what, and causes this or that to happen.....is there such a diagram anywhere??

Thanx Guys,
Shorebilly

__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG

Mine has that same setup. I wonder if it's specific to California models. Do you have a tall air filter just behind the headlights?

__________________
1978 Ford F-150 351M
2002 Kia Spectra 1.8l 5-sp
1985 Volkswagen Scirocco 8V 1.8l 5sp
1985 MB 300D Turbo California

"Die Natur verabscheut Vakuum"

I would like to wish you luck in your quest to figure out the finer points of the '85 vacuum system.

I have one of those valves near the fuse box on my car in addition to the one you're talking about by the wheel. I think they're also called electric switch-over valves. Not sure if there's officially a dash there or not.

Do you have the blue plastic transducer on the driver's side fender wall? That's kind of near the fuse box as well. It sends a vac line to the transmission.

__________________
Ralph

1985 300D Turbo, CA model
248,650 miles and counting...

I believe there's a diagram on Braingears. Look for the one specifically labeled "1985 California."

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970

Howdy,

Nope, mine is a "Federal" model......

SB

__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG

Yup,

I have the Blue Transducer....don't know what it's function is....yet.....but it holds Vacuum.....

Found my leak...I think.....it seems as if the "Vacuum Converter" may be the culprit......

Will begin a new thread on that item.......

SB

__________________

Diesels:
'85 300D, "Max, Blue Benz", 155K, 27.0 MPG
'84 190D 2.2, "Eva, Brown Benz", 142K, 40.2 MPG
'77 240D (parts car)
'67 Eicher ES 202 Tractor "Otto" (2cyl, Air Cooled, 30HP)
Gassers:
'94 Ford F-150, "Henry", 170K (300 Six) 17.5 MPG
'85 190E 2.3, 148K....Parts Car
'58 Dodge W300M Powerwagon (Flat Fenders) Less than 10 MPG