300d 4 ME

I have just bought a 1976 W115 300d. From what I have been told this is fairly rare. I have many vacuum leaks, problems, etc. But the main one is the ignition switch. The car will not turn off, luckily there is the stop lever under the hood. The fuel cut off valve is working fine, but i am not getting any vacuum. (Vacuum pump works o.k.)

Is there any diagrams, for vacuum for this car?

Or any one have a guess where to look for the problem?

Thanks!

Outre

Sorry about the crowded spacing; can't seem to find away to space them.You can test the Vacuum Shutoff Valve on the Fuel Injection Pump by getting a section of Vacuum Hose and connecting that to the Fuel Injection Pump Shutoff Valve.Oil comes out of the old hose it is an indication that your Vacuum Shutoff Valve may have a hole in the diaphragm.While the Engine is running use a hand held Vacuum Tester Pump or simply suck on the end of the newly installed Hose. If you Engine shuts off the Vacuum Valve on the Fuel Injection Pump is OK.There is also another Vacuum Valve on the Steering Wheel lock. That can go bad and the Hoses can also go bad there.Leaks in other parts of your Vacuum System can cause the Shutoff not to work. When you get that Vacuum Diagram you can by pass the other systems by removing and plugging off both ends of the Vacuum lines that go to them.If you are also having to use excessive pressure on your Brakes it could be an indication that your Vacuum Pump is not supplying enough Vacuum. But, check for system leaks first.

300d 4 ME

Allright, I have tested the shut off valve, it works fine. Now thinking about it ,it does make since about all of my vacuum leaks,there are many,many leaks...

Could you send me that link again, diagram etc. It said image not found.

Thanks!

Outre

If you plan to keep your Car you might want to consider buying the Factor Service Manual CD set direct from Mercedes. $19.99+$7 shipping.I will Email the specifics.

SignalRed

Indeed the car will not shut off if you do not have a correct vacuum.

300d 4 ME

Its been a little since my last post. I found the problem, after going over everything. The problem was on the vacuum side of the ignition switch. It was leaking air.at that vacuum switch.

So for the mean time I installed a brass cut off fitting under the steering column. Works great.


Thanks for all the help!

300d 4 ME

The valve I made worked great, but kinda got in the way.. I went on a search of what I needed to do. I found out that there is a vacuum lock valve -on the steering switch. It works great, a very easy fix. The proper name is

Vacuum Lock Valve

AutoHausAz carry's these.

Part #
0004600284

http://www.autohausaz.com/search/pro...Vacuum%20Valve

Outre

Thanks for your posts. So many people ask questions and never come back and say what solved their problem.
You Posts will help someone else with the same problem!