TM 5-3895-379-23-1
0003
FUEL SYSTEM
1. General.
a. When the engine is turning, fuel is pulled from the fuel tank through the fuel/water separator by the
fuel lift pump. The fuel lift pump sends the fuel at low pressure to the fuel filter. From the filter, the
fuel is sent to the fuel injection pump. The fuel injection pump sends high pressure fuel through the
high pressure fuel lines to the fuel injector nozzles. The four fuel injector nozzles spray fuel into the
cylinders of the engine. Any fuel not used by the fuel injector pump is returned to the inlet side of
the fuel filter.
b. The engine is equipped with a cold start heater to warm fuel for starting the engine in cold weather.
2. Fuel Tank. The fuel tank is part of the fuel, hydraulic tank assembly. The fuel tank is located on the right
side of the assembly. The fuel and hydraulic tanks are welded together, but are separate containers. The
capacity of the fuel tank is 55 gal (208 Liters) of diesel fuel or JP-8.
3. High Pressure Fuel Lines. The high pressure fuel lines deliver fuel from the fuel injection pump to the fuel
injector nozzles.
4. Fuel/Water Separator. The fuel/water separator separates any water from the fuel before reaching the fuel
filter and the engine. The water that is separate from the fuel collects at the bottom of a glass bowl located
on the bottom of the separator. The drain valve is located at the bottom of the bowl and can be used to drain
the water from the fuel/water separator.
5. Fuel Lift Pump. The fuel lift pump delivers fuel to the fuel injection pump. The manually-operated lever
primes the pump by removing air and introducing fuel. Priming is needed after the fuel system has been
opened or air is in the system.
6. Fuel Filter. The fuel filter removes foreign matter from the fuel before fuel into the fuel enters the fuel injector
pump.
7. Fuel Injection Pump. The fuel injection pump forces high pressure fuel into the fuel injector nozzles. The
fuel injection pump is gear-driven from the crankshaft. The fuel injection pump needs fuel for lubrication.
The precision parts are easily damaged. For this reason, the engine must NOT be started until the fuel
injector pump is full of fuel that is free of air.
8. Fuel Injectors. The fuel injectors spray fuel into the cylinders of the engine.
9. Cold Start Heater. The cold start heater is installed in the inlet manifold to heat inlet air in cold weather.
When activated by operator controls, the current from the electrical wire causes the coil inside the heater to
become very hot. A small amount of fuel will flow through the heater as the engine is cranking.
0003-4
03/15/2011Rel(1.8)root(thrywp)wpno(G00006)
