ignition switch
 

Just purchased a 78' 300D. Battery keeps dying, ignition is screwed. When I crank the key, it does'nt pop back over and stays in the far right position (it keeps cranking the starter and does'nt allow alternator to recharge the battery?) Only Way I can get it to run is after I jump the car, I turn the key all the way over to off position but the engine does'nt die. It keeps going, and I have no electronics of course. I turn off the engine by pulling the throttle linkage to the passenger's side.

My ignition switch is bad?!?!??

Also, once I got home I realized there were no brake lights and diagnosed the problem. Due to there not even being wires going to brake switch, they don't work. Which I find very strange, considering the fact that there is absolutely no wire under the dash at all for the switch! One more thing. It seems the oil needs a changingreal bad, it is quite dirty. What would someone recommend for me to use? The engine has 109,000 miles.

RE: ignition switch
 

You can replace either the tumbler or electric portion of the switch separetly.
Diesel motor oil looks dirty 20 miles after a change.
Get that brake light fixed!
Engine shutdown may be a switch and/or vacuum issue.