Engine Will not turn off.

I changed the Oil in 1980 MB 300SD and went to start it up and let it run a while. Well when I went to turn of the Engine it wouldn't turn off. All the other accessories turned off like the radio but the engine kept going. I turned the key all the way to the off position. I had to pop the hood and push the STOP button on the accelerator to turn the engine off. What happened and how can I fix this problem?

[Palangi]

You have most likely pulled a vacuum line loose back there by the top of the oil filter. Should be easy to spot and fix.

[rickjordan]

I second Paul's suggestion. When you shut off a diesel, all you are really doing is starving it of fuel. When you turn the key there is a vacuum switch that's suppose to shut off the fuel. If I remember correctly, there is a vacuum line that goes up to the ignition switch itself. Maybe that is the problem. Eitherway, it's a vacuum leak somewhere.