DT66

Ok, first we need to know if the ECM is properly booting up at key on. At key on you should get the yellow "Warn engine" light and/or the red "Stop engine" light coming on for a bulb check. The ECM turns these lights on. No lights means the ECM is not getting power. Another check for the ECM is to watch the tach while cranking. If the tach shows some rpm during cranking this means the ECM is getting power and the cam sensor is also reading properly. Are you sure the engine is getting enough fuel?

 

Run a test fuel line from the inlet of filter to the tank, reprime and see if starts. Does this engine have a hand primer on it? If it does, you should be able to pump enough fuel up to the head with that. You have to vigorously pump it while cranking to get the engine started. If it still does not start you have a restriction on the inlet side or sucking all air. If it will start while pumping the hand primer, but dies once you stop I would say the fuel pump is gone.