COOLING SYSTEM
DESCRIPTION OF COOLING SYSTEM
COMPONENTS OF 480 ENGINE COOLING SYSTEM
Engine cooling system is used to cool engine to
prevent the engine from overheating, ensuring the
normal operation of engine. It is composed of the
timing belt-driven water pump, transverse radiator,
water tank, water pipe, thermostat, temperature control
switch of electrically-driven fan and water temperature
sensor.
WORKING PRINCIPLE OF COOLING SYSTEM
When the temperature of engine coolant is
relatively low, the thermostat shall turn it off, and the
coolant shall circulate and flow among the cylinder
block, water pump and warm air exchanger. This kind
of circulation is called small circulation.
When the temperature of engine coolant is
relatively high, the thermostat shall turn it on, the
coolant shall flow into the radiator, the electrically
-driven fan shall operate to lower down the temperature
of coolant. And then the coolant shall flow back to the
engine cylinder block. This kind of circulation is called
big circulation. As the big circulation operates, the
small circulation shall also play its role.
As the engine works under normal work
temperature the engine coolant shall expand. Under this
circumstance, the overflow valve installed on the
thermostat chassis shall turn it on, the coolant shall
flow into the expansion water tank through the
overflow pipe; and as the system cools down, the
coolant shall flow back to the water pump inlet from
the expansion reservoir.
The operation of electrically-driven fan is
controlled by the thermo-switch installed on the right
water chamber of radiator. When the contact points of
thermo-switch meet together, the electrically-driven fan
shall run. The water temperature sensor is fitted on the
back of cylinder head lying at the side of exhaust pipe.
Hose
Warm Air/Heat Exchanger
Expansion Tank
Pressure Cap
Engine
W
at
er
P
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p
Inl
et
Cooling Water Pipe Assembly
Electrically-Driven Fan
Thermostat Chassis and
Thermostat Assembly
Water Temperature Sensor
Hose
Hose
Hose
Hose
Radiato
Thermo-Switch
Hose Assembly
Hose Assembly