I'm assuming the engine is connected to a pressure washer pump with an unloader valve that lessens load on the engine when you are not spraying water?
Does that engine have a fuel shutoff solenoid in the fuel line or maybe an electric fuel pump? If the magnetos are not grounding out and shutting off spark, but the solenoid or fuel pump is shutting off fuel, the engine may run until the carb runs out of fuel.
As Army says, check the wiring going to the magnetos to make sure the magnetos ground out when the shut off switch is in the OFF position.
As for fuel consumption, is the unloader valve inoperative putting load on the engine at all times?
Does that engine have a fuel shutoff solenoid in the fuel line or maybe an electric fuel pump? If the magnetos are not grounding out and shutting off spark, but the solenoid or fuel pump is shutting off fuel, the engine may run until the carb runs out of fuel.
As Army says, check the wiring going to the magnetos to make sure the magnetos ground out when the shut off switch is in the OFF position.
As for fuel consumption, is the unloader valve inoperative putting load on the engine at all times?
