Abstract: A fuel system and method for priming a diesel engine fuel system after assembly or when run out of fuel in which the system has a filter that can trap air allowing drainback of fuel to the tank. The system is provided with a fuel priming connection to the injection pump inlet, the connection having a closure for shutting the connection when not in use. A mechanically openable check valve, such as a Schraeder valve, is a preferred form of closure. The system is primed by reverse flow of fuel from the priming connection through the filter to the fuel tank to virtually eliminate trapped air from the system. The engine may then be started with a minimum of cranking. The engine may be restarted after running out of fuel by partially filling the tank and operating the normal feed pump while bleeding air from the system through the priming connection, which is closed prior to engine starting. The engine may then be reprimed after shutdown if required.