I am a new member. After driving my 1984 300SD with A/C on and driving more than 30 min. in the Texas heat, if I turn off the engine and wait 5 to 15 min. the engine will not rotate when I try to start it again. Glowplugs and accessories turn on but it won't crank. Sometimes with moving the automatic transmission shift through the positions the car will then start. When car cools down it starts fine every time. Neutral safety switch was replaced last year. Any suggestions as to what is the problem and how to repair it? Thanks.

 

Does the starter turn slow or not at all?

 

When the symptom occurs there is no start at all (after the glow plug glows) and the seat belt buzzer stops). I am not sure if I can hear the solenoid click.

I don't know exactly what is meant by "slop" in the automatic shifting, but the shifting seems normal to me (i.e., there is no slipping).

 

FI means in the actual mechanism itself, not the transmission. Does the shifter feel loose?

 

Try lightly pushing on the shifter towards the Park position while turning the key to start the car or try to start the car in neutral.

 

Also a new Neutral Safety Switch put in last year does not mean it is OK now.

You actually diagnosed the problem area:

"Sometimes with moving the automatic transmission shift through the positions the car will then start."