Ignition Saftey Switch
 

Hows it goin guys. Im new on this board, aswell as fairly new at being a mercedes engine enthusiast. I take pride in fixing whatever is within my own ability and that is why Im asking from the experience of others. I have a 82' 300 sd that I love to death but for as long as Ive had it, its given me a problem with the park/neutral saftey switch. Often times after its been on a long drive it wont start in park and I have to move the shifter back and forth from park to neutral until it starts. I have a feeling that it might just require some contact cleaning, but I have no idea where its located. If it is a part that I need to replace, is there any place you guys suggest to order from? Can this defect be caused or lead to any other problems on the car? Thanks a lot guys, I really appreciate it

If there's more than 1cm of fore-aft play in the shift lever then your first step is to fit new shift rod bushings. I expect you'll look under the car and say, "What bushings?" There used to be a plastic bushing at either end of the rod that connects the bottom end of the shift lever and the transmission.

If shift linkage is tight, and in my SDL is there is practically no play with new bushings, the next thing is to adjust the neutral start switch on the side of the transmission. You can't miss it. It's the plastic box held by 2 10mm head bolts. My adjustment rule of thumb is to set the shift lever in reverse and have someone yell out whether the reverse lights are on or off as I swivel the neutral start switch. I set it so the setpoint is halfway across the span that represents when the reverse lights are on.

Sixto
95 S420
87 300SDL

Thanks! I was searching on here and got lots of info. Sorry for the question if it seems trite.

The FastLane link at the top of this page is a great source of parts with the service you should get for what you pay at a dealership.

Sixto
95 S420
87 300SDL