TM 5-3810-300-24 & P2
Fuel Pump.
A positive displacement gear type fuel pump is attached to the blower and driven off the rear end of the lower blower
rotor.
A spring-loaded relief valve, incorporated in the pump body, normally remains in the closed position, operating only when
the pressure on the outlet side (to the fuel filter) becomes excessive due to a plugged filter or fuel line.
The fuel pump incorporates two oil seals. Two tapped holes are provided in the underside of the pump body, between the
oil seals, to permit a drain tube to be attached. If fuel leakage exceeds one drop per minute, the seals must be replaced.
Fuel Strainer and Fuel Filter.
A replaceable element type fuel strainer and fuel filter are used in the fuel system to remove impurities from the fuel. The
strainer removes the larger particles and the filters remove the small particles.
The fuel strainer and fuel filters are basically identical in construction, both consisting of a cover, shell and replaceable
element. Since the fuel strainer is placed between the fuel supply tank and the fuel pump, it functions under suction; the
fuel filters, which is installed between the fuel pump and the fuel inlet manifold in the cylinder head, operates under
pressure.
Fuel Stop Switch.
Depressing the engine stop button in the cab allows power to energize the fuel stop switch. The fuel stop switch actuates
a solenoid that places the injector racks in the no fuel position.
Engine Air System Components. (Illus. 4-5).
A charge of air, forced into the cylinders by the blower, sweeps all of the exhaust gases out through the exhaust valve
ports, leaving the cylinders filled with fresh air for combustion at the end of each upward stroke of the pistons.
This air also helps cool the internal engine parts, particularly the exhaust valves. At the beginning of the compression
stroke each cylinder is filled with fresh, clean air which provides for efficient combustion.
The blower supplies fresh air required for combustion and scavenging. Two hollow three-lobe rotors are closely fitted in
the blower housing which is bolted to the cylinder block. The revolving motion of these rotors pulls fresh air through the
air cleaner or air silencer and provides a continuous and uniform displacement of air in each combustion chamber. The
continuous discharge of fresh air from the blower creates a pressure in the air box.
Air Cleaner.
The air cleaners are the heavy duty dry type. The dry type air cleaner consists of a removable cover attached to the air
cleaner body which contains a replaceable paper filter cartridge and a dust cap. Air entering the air cleaner is given a
centrifugal pre-cleaning by a turbine type vane assembly. Air rotates at high speed around the filter element throwing the
dust to the outside where it flows.
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