Fifteen years ago:
I used my Honda 350 motorcycle to jump start a Mercedes Benz diesel.
#1. Connect cables.
#2. Raise the RPM to 1200.
#3. Relax for 3/4 hour.
#4. Disconnect jumper cables.
#5. Start car.

As I recall, the Honda 350 motorcycle only puts out 15 AMP, which takes a long time to charge a large battery.
I disconnect the cables before starting because it acts like a dead short across the weaker system, and can fry the alternator.

__________________
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