TM 10-8145-222-23
0003
DIESEL ENGINE CONTINUED
Water Temperature Sensor (WTS). The water temperature sensor (Figure 10, Item 1) senses engine water
temperature and is located near the top rear portion of the engine. The microprocessor will stop the refrigeration unit
when water temperature exceeds 110 3C (230 5F).
Figure 10. Water Temperature Sensor.
Lubricating System
The engine lubrication system consists of an oil strainer, oil pump, relief valve, oil filter cartridge, and oil switch. Oil
pump sucks lubricating oil from oil pan trough oil strainer. Oil flows down to filter cartridge for further filtering. Oil is
then forced to the crankshaft connecting rods, idle gear, camshaft, and rocker arm shaft. Splashing or dripping oil
from these parts provide lubrication for pistons, cylinders, small ends of connector rods, tappets, pushrods, inlet and
Oil Filter Cartridge. When filter element is clogged and oil pressure in inlet line is greater than the outlet line, a
bypass valve opens and oil flows from inlet to outlet, bypassing the filter element.
Oil Pressure Switch. This switch is mounted on the cylinder block. It serves as a warning to the operator that
lubricating oil pressure is poor. If oil pressure falls below 49 kPa (0.5 kgf/cm2, 7 psi), oil warning lamp lights up. When
lamp lights up, the operator should immediately stop the engine and check for the cause of pressure drop.
Cooling System
The cooling system consists of a radiator (Figure 12, Item 1), condenser fan (Figure 12, Item 2), water pump
(Figure 12, Item 4), and a thermostat (Figure 12, Item 3). The radiator and condenser is an assembly housed in one
component. A standard mixture of antifreeze and water provides coolant protection from both extremes of hot and
cold. The water pump provides coolant flow from the hot engine cylinder block (Figure 12, Item 5) through the radiator
core where the fan pulls air through the radiator for cooling. The thermostat controls coolant flow to maintain a
constant engine temperature.
