2001 Ford Excursion 7.3L Diesel Supplement 2nd Printing - Page 4

Diesel information DIESEL ENGINE INFORMATION The diesel engine fuel system consists of: • a frame-mounted electric fuel supply pump • an engine mounted fuel filter/water separator • a fuel restriction sensor • a unit injector for each cylinder The combination fuel filter/water separator removes both water and impurities from the fuel. The filter should be changed at the recommended service interval. Refer to the "Service Guide" for more information. The filter bowl should be drained at regular intervals or when the "WATER IN FUEL" light illuminates in the instrument cluster. The fuel injectors are located in the center of the combustion chambers in the cylinder head between the rocker arm assemblies. The glow plug system and fuel injection system are controlled through the powertrain control module (PCM). Fuel is drawn from the fuel tank by a frame-mounted electric fuel pump. The fuel pump provides pressurized fuel to the engine and is electronically controlled by the fuel pump PCM relay. The fuel pump contains a pressure relief valve for overpressure protection in the event of restricted flow. Lubrication system It is important to change the engine oil at the recommended service intervals, because oil viscosity is important in maintaining the oil pressure required to actuate the fuel injectors. Extended oil change intervals can negatively affect engine performance and fuel economy. Pressurized oil from the turbocharger is also used to actuate an exhaust backpressure warm-up system (if equipped). Pressurized oil from the turbocharger is routed to the exhaust backpressure actuator. During exhaust backpressure operation, the engine's sound will be altered and you may notice a change in engine performance while it's engaged. This function occurs only during cold weather warm-up cycle. 4