9. FUEL SYSTEM OPERATION
The HMMWV diesel fuel system operation is identical for both models covered in this manual. The system
cleans and supplies fuel for the engine. Major components of the fuel system are:
FUEL PUMP - Draws fuel from fuel tank through the supply line and pumps it to the fuel filter.
FUEL RETURN LINE - Carries unused fuel from the injection pump back to the fuel tank.
FLJEL SUPPLY LINE - Carries fuel from fuel tank to the system.
FUEL TANK - Stores 25 gallons (95 liters) of diesel fuel.
FUEL FILLER CAP - Located at right rear side of vehicle, the cap is removed to permit fuel tank
FUEL INJECTORS - Receive metered fuel from the injection pump and spray fuel into the
FUEL FILTER/WATER SEPARATOR - Filters water and sediment from fuel before fuel enters
the injection pump.
INJECTION PUMP - Directs metered and pressurized fuel to the eight injector nozzles. It is
mounted on top of the engine under the intake manifold.