My classic 300d has started to act up,I was running it all day and I turned it off and when I went back to start it up it wouldn't start I taped the starter and it started but it only runs for maybe 30-60 seconds when the project engine light Come on and it shuts off, I turn the ignition off to reset it and it starts right up then does the same thing, and suggestions?

If it has Murphy switches. It is very possible one of the sensors went bad. If you have a wiring diagram look threw it and follow those circuits.