Mercedes Benz repair: starting 1976 300d mercedes benz, neutral safety switch, battery selection

Question
When the car is cold, it will start fine. when you go somewhere it might start it might not. It will not turn the starter over nothing. You let the car sit awhile it will start after the glow plug cycle kicks in. If it is not cool enough it won't start.

Answer
Answer:
I would suspect:
* NSS failing = (Neutral Safe Start switch).
* Starter failing.
* Bad contact/Broken ground cable, transmission bell housing to body.

The NSS is an easy DIY.

Broken Neutral Safety Switch and replacing shifter bushings
http://www.mercedesshop.com/shopforum/showthread.php?p=646647

Replacing all shifter bushings on W126 - p.1
http://www.mercedesshop.com/shopforum/showthread.php?t=112582


Here are starter threads that may help you.

Starter health is important to your diesel!!!
http://www.mercedesshop.com/shopforum/showthread.php?p=739798

Gear reduction starter for W126 diesel?
http://www.mercedesshop.com/shopforum/showthread.php?t=148100

Tackling a starter, need suggestions (and sympathy)
http://www.mercedesshop.com/shopforum/showthread.php?p=1001659



These may be helpful for other issues. :)

Battery Safety
http://www.mercedesshop.com/shopforum/showthread.php?p=1057827

Battery selection / Charging System / jump starting / cold weather battery issues
http://www.mercedesshop.com/shopforum/showthread.php?p=1058189

Glow plugs link thread         
http://www.mercedesshop.com/shopforum/showthread.php?p=1019018