My wife was given a 1985 300D MB and has fallen in love with it. After sitting around for months, I started tinkering with it and have found myself strangely attached to it, too. So, I'm trying to get it road-worthy. The car runs but doesn't shut-off. After searching and finding the links for the shut-off valve, I have found several vacuum lines and connection with no vacuum lines. I have printed some diagrams but need help identifying some parts for a starting point. Here they are:

What is the round part and where does the missing vacuum line go? Also, the part directly to the left of it has a missing vacuum line, too. What is that part and [again] where does this line go?



These come directly through the firwall, I think the line with the white filter (bottom) is for the EGR, right? What is the one with the brown line coming out of the yellow filter/check valve(?) and last, what is the line that is block with a bolt (see 4-way Tee near top)?



Thank you in advance for any assistance. Hard to search for something if you not sure what it is your looking for.

I too am new to these machines and cannot offer you much help but I will say that while tinkering with my brake problem and vac lines, I found that indeed a 240D engine will not shut off at the ignition if you disconnect a vac line to what looks like a diaphragm on the injection pump.

The other vac lines on mine go to the power door lock system which failed years ago and have been plugged.

HTH
B

__________________
1978 240D 4 spd. manual
1983 Toyota Land Cruiser BJ42 Diesel 5 spd.

Both biodiesel powered

Well, the 85 is a little different than other years, so I can't help much with the first photo. In the second photo, the yellow check valve feed the door locking system. The blocked line (with the screw) in the 4 way connector should be connected to the yellow check valve. It may be blocked off due to a leak in the door locking system someplace.

http://dieselgiant.com/mercedesvacuumtroubleshooting.htm

Thank you! The car doesn't have door lock controls, so I can block this off? Or does the doors automatically lock when it reachs ~10 mph? Sorry for the novice questions, but appreciate everyone's help.

The way the doors are supposed to work is that the drivers door is locked/unlocked manually and the other doors, trunk, and fuel door are automatically locked/unlocked with vacuum (they "follow" the driver's door). The disconnected yellow check valve is the supply for that system. In your case, it's been disconnected so the door locks are completely manual.

Here's your vacuum diagram for the '85. Not many vehicles with this setup, however.