BX2370 Mowing the field ,engine died,disconnected the fuel line at injector pump and finally got fuel ,ran for a few hours and died again . thought the fuel pump was going bad. Replaced the fuel pump and it ran fine for a few hours and died again. blew the fuel lines out and got fuel, ran fine for a few more hours then died again. Replaced with another fuel pump and ran fine for another hour and died again. i can hear the fuel pump running but no fuel at injector pump . any ideas ? Fuel filters have been recently changed.