that glow plug wiring will really help me out!! thanks...but I have the original om617 alternator and it has 2 about 12ga red wires and about a 14ga blue wire coming from it...don't see any noticeable spot for a larger gauge wire and in mercedesdiesel4x4 they say to hook up the blue wire to a green wire that has a green w/orange stripe next to it and the 2 red ones to a 10ga gray or black wire...cant remember the color...but I wasn't able to find any wires that matched that description...thanks for the quick reply!!

 

Ok try here. STD

 

I just came across this video that shows the MB glow plug relay module out of a 300D (post '81 I believe) hooked up to a battery and some lights to represent dash lamp and glow plugs. This helped me out a ton. Purple wire goes to starter solenoid and after this is connected and removed from 12V it will turn off the glow plugs. I have the same MB relay and I replicated the setup shown in the video with a regular 9V battery some LEDs and resistors I had laying around and had the same results except for the 30 second timer shut-off, mine timed out after about 10 seconds. This is likely due to the lower voltage battery I was using.