D2 Electric Starter Selenoid - Advice Needed

[quote="rhartwick"]My D2 has a 24V electric start on the main diesel. It quit the other day, staying on when the solenoid burned up in the ON position - not good. Taking it off, someone had put on a plain old 12V universal auto solenoid, so it is no wonder it eventually burned up.

What amperage solenoid would I need to prevent this happening again? I found this one at NAPA

https://www.napaonline.com/en/p/ECHST88

Think that will work, or do I need something heavier duty?[/quote]

I picked up what seems to be a quality 200 amp solenoid on line for $70.00 or so a few months ago. Not sure the name but something along the lines of Energizer or close. No issues with it to date.

I’ve only had one starter solenoid actually “burn” but had plenty get the contacts stuck. That usually happens when the batteries are close to dead. In that situation, the contacts are closed longer and the starter may pull more amps than normal, not sure about that, but the net result is they are very prone to weld.

Those eBay series/parallel switches are built for that duty and should work fine for your needs. There will be a couple extra small terminals on the unit for creating the “parallel” circuit when the main contacts are open, but you can just ignore them unless you want to actually operate with a 12 volt charging system. The series/parallel electrical system was an interim design between the old 24 volt on everything and the newer 12 volt on everything designs. At the expense of some complexity in wiring and cables, the series/parallel system allowed the best of both worlds.