How do you prime a Kubota diesel engine?

If you're asking about a Kubota utility tractor, the fuel tank is above the filter assembly and the fuel will gravity feed through the filter when the ring nut is loose and of course you open the shutoff valve. Once the filter housing fills up (and you spill a little diesel), close the ring and then crank on the engine until the fuel gets into the pump. It should crank in less than 30 seconds with the fuel control set at half-throttle or higher. This info is based on experience for a Kubota M4700 tractor.