Patent ID: 8909457

Claim:
A method of operating a dual fuel engine, comprising the steps of: operating a dual fuel system in a regular mode; operating the dual fuel system in a limp home mode; accumulating liquid fuel in a gaseous nozzle chamber of each fuel injector of the dual fuel system over a plurality of engine cycles when operating in the limp home mode; transitioning from the limp home mode to the regular mode by displacing the accumulated liquid fuel with gaseous fuel; injecting liquid fuel from a first nozzle outlet set and gaseous fuel from a second nozzle outlet set into an engine cylinder when operating the dual fuel system in the regular mode; injecting liquid fuel from a first nozzle outlet set but not injecting gaseous fuel from the second nozzle outlet set into the engine cylinder when operating the dual fuel system in the limp home mode; and injecting liquid fuel from a first nozzle outlet set and injecting the accumulated liquid fuel from the second nozzle outlet set into the engine cylinder during the transitioning step.