I might hold the record: I made it home from Alasks to PA with a dead alternator in a '80 300SD. I had a battery charger with me so every night I charged the battery and that was enough to keep the engine running all the next day.

It got a little dim in Billings Montana when it started getting dark and the headlights looked like candles, but the engine ran the same as ever.

So yes the mechanical injection Diesels will run without electrical energy once started but the newer electronic injection and computer controlled will not. That sounds to me for like a vote for mechanical fuel injection.

P E H