TM 5-3820-245-14&P
GENERAL DESCRIPTION
The two-cycle diesel engines covered in this manual have the same bore and stroke and many of the major working parts
such as injectors, pistons, connecting rods, cylinder liners and other parts are interchangeable.
The In-line engines, including the inclined marine models, include standard accessories such as the blower, water pump,
governor and fuel pump, which, on some models, may be located on either side of the engine regardless of the direction
the crankshaft rotates. Further flexibility in meeting installation requirements is achieved with the cylinder head which can
be installed to accommodate the exhaust manifold on either side of the engine.
The meaning of each digit in the model numbering system is shown in Figs. 2 and 3.
The letter L or R indicates left or right-hand engine rotation as viewed from the front of the engine. The letter A, B, C or D
designates the blower and exhaust manifold location on the In-line engines as viewed from the rear of the engine.
Each engine is equipped with an oil cooler, replaceable element type lubricating oil filter, fuel oil strainer, fuel oil filter, an
air cleaner or air silencer, a governor, a heat exchanger and raw water pump or a fan and radiator, and a starting motor.
Full pressure lubrication is supplied to all main bearings, connecting rod bearings, and camshaft bearings, and to other
moving parts.
Oil is drawn by suction from the oil pan through the intake screen and pipe to the oil pump where it is pressurized and
delivered to the oil filter and the oil cooler. From the oil cooler, the oil enters oil galleries in the cylinder block and cylinder
head for distribution to the main bearings, connecting rod bearings, camshaft bearings, rocker arm mechanism and other
functional parts.
The cooling system has a centrifugal water pump which circulates the engine coolant through the oil cooler and water
jackets. The engine temperature is regulated by a thermostat(s).
Fuel is drawn from the supply tank through the fuel strainer and enters a gear type fuel pump at the inlet side. Upon
leaving the pump under pressure, the fuel is forced through the fuel filter into the inlet manifold where it passes through
fuel pipes into the inlet side of the fuel injectors. The fuel is filtered through elements in the injectors and then atomized
through small spray tip orifices into the combustion chamber. Excess fuel is returned to the fuel tank through the fuel
outlet galleries and connecting lines.
Air for scavenging and combustion is supplied by a blower which pumps air into the engine cylinders via the air box and
cylinder liner ports. All air entering the blower first passes through an air cleaner or air silencer.
The engine may be started by an electric starting system.
The engine speed is regulated by a mechanical type engine governor, depending upon the engine application.
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