Abstract: An engine shutoff device includes provisions to shut down an internal combustion engine under conditions outside the normal operating limits of the engine. While the engine is idling, shutdown is initiated by fuel cutoff when engine oil pressure is below a predetermined level. As engine speed increases the low oil pressure cutoff provided in the idle range is isolated from the system so that shutdown again by fuel cutoff will occur if oil pressure drops below a second predetermined level relatively greater than first predetermined level. Engine shutdown is also initiated by fuel cutoff when either coolant temperature or lubricant temperature is excessive. The engine can be manually shut down by an emergency valve that causes cutoff of the fuel and air supply. Finally, the device initiates engine shutdown by both fuel and air cutoff when an overspeed condition occurs.