@foton: no ChatGPT said to check the spark plug gaps. So much for AI.
@Tazza: "manually pushing the stop solenoid into the run position" where would I find the stop solenoid? or do you mean the brake solenoid or the fuel pull solenoid?
I found a YouTube video of a 463 with a similar issue, that suggested a fuel Time shutdown.
What else could it be.
I asked ChatGPT - apparently I should check my spark plugs. I've already done that. That's always my first call when I have a problem with a deisel.