Key Won't Shut Down Engine, 240D
 

I tried searching "won't stop" but could not find my answer, so I apologize for asking if it has already been asked.

I have lots of experience keeping old cars going, but this is my first car other than just a Ford or Chevy. It is an 81 240D. I've had it a couple of months and it came time to change the oil. All went well, except after that the key will no longer kill the engine.

I found the stop lever, so I'm still not afoot, but I can't shut off the engine with the key.

Thanks ahead of time to anyone who might can tell me what circuit to run down.

Joe

It's a vacuum problem. Either a vacuum leak or a failed shut off diaphragm. A quick check is to remove the brown vacuum line off the shut off valve down between the injection pump and oil filter housing. Replace it with a length of vacuum hose. Suck on the hose with the engine running. If the engine shuts down, you've got a vacuum problem somewhere else other than the shut off valve. If it won't shut down with 3 strong sucks, or you get a mouthful of engine oil, then the shut off diaphragm has a hole in it and needs to be replaced.

For further searching, "shut off valve". Should be fairly consistant information/troubleshooting among most pre-85 models (in theory, at least).

Welcome to the forum Joe,
Starting at the injection pump & working your way back is the best way to find your problem. Do you have any other vac related problems? Central locking etc?
We hope you will get all the help you need on the forum.
Often many of us, after a fruitless day of trying to find a problem, pray for a little 'divine intervention' , having you here maybe just what the doctor ordered!! (sorry I couldnt resist that!)

Good Luck with your car & compliments of the season!!

shut down
 

If it turned of normally before you changed the oil and now won't, then you have loosened or dislodged a vacuum line. Probably near the oil filter. Go over the lines close to the filter and push them all into their respective connectors and give it a try. Even if they look good they may have slipped out enough to leak.
Jon J
81 240D

THANKS!!!!!!!!!!!

I had not looked closely enough to discover that the shutdown was vacuum related. Sure enough, I found a loose vacuum line near the oil filter.

All is well with it for now. There a few little things that I will attack when the weather gets better and be bothering you all again, but for now I have a reliable vehicle to drive.

Joe

Welcome to the forum Joe, I am sure you will find PLENTY here to read about, and as you get more familiar with your vehicle, and spend more time here on the forum your addiction to MB's will grow!