5-2 COOLING AND LUBRICATION SYSTEM
COOLING SYSTEM
DESCRIPTION
The engine is cooled by the forced circulation of engine coolant, using a high-capacity, centrifugal water
pump, through water jackets formed in the cylinder and cylinder head, and through the radiator. The tube-
and-fin type radiator is made of aluminum, which is characterized by lightness in weight and good heat dissi-
pation.
A wax-pellet type thermostat is used to regulate the flow of engine coolant through the radiator. As the cool-
ant temperature rises to about 75°C (167°F) the thermostat valve unseats and a normal coolant flow is
established. At about 90°C (194°F) the thermostat becomes completely open and, as a result, heat is
released to the atmosphere through the radiator core.
Referring to the following illustration, the thermostat is in the closed condition, so that engine coolant recircu-
lates through the route comprising the water pump, engine, by-pass hole of the thermostat and radiator in
the regulated condition.
1
Impeller
2
Radiator cap
3
Radiator
4
Thermostat
5
Cooling fan thermo-switch
6
Coolant temperature switch
To Next Page
Loading...
