ELECTRICAL SYSTEM.

TM 9-2320-279-20-1

Vehicle

Operation

Systems

(Cont)

c. Cooling System. (fig. 1-12) The pressure

type cooling system protects the engine by

r e m o v i n g heat generated during the combustion

process. Pressure within the cooling system is

regulated by a pressure release in the radiator

filler cap (1). The hot coolant flows from the

engine to the top radiator

tank (2) and through the radiator core (3) where a

stream of air removes heat. This stream of air is

drawn through the core by an air-activated fan (4).

A water pump (5) draws the coolant from the

bottom of the radiator and pushes it through the

engine repeating the cooling process.

T h e r m o s t a t s (6), mounted in each coolant outlet

e l b o w , remain closed until the coolant approaches

a predetermined temperature at which time they

o p e n . When the coolant temperature drops below

the thermostat rating, they close. An air vent

line (7) between the radiator (2) and the water

pump inlet removes air trapped in the engine

when the cooling system is being filled.

Cooling

System

(fig. 1-13) The voltage and current for the electrical system are indicated

1-17. ELECTRICAL SYSTEM.

by a battery gage (1) and an ammeter (2) located on the dash panel inside the drivers compartment. Circuit

breakers (3) located in the cab protect the main circuits. Electrical power is provided by four 12-volt

series-parallel connected batteries (4). Power is distributed throughout the vehicle by wiring harnesses.

The harnesses are interconnected by pin connectors. Connectors are provided at the rear of the vehicle to

supply power for towed loads. A heavy duty starting motor (5) is mounted on the engine flywheel housing

and provides the cranking power necessary for starting the engine. The voltage regulator (6) is mounted on

the belt driven alternator (7) and maintains a 24-volt level for battery charging.

Figure 1-13. Electrical System.