Cooling System; General; Cooling Fin; Water Pump - wsm wg972-e4 Workshop Manual

WG972-E4, WSM

3. COOLING SYSTEM

[1] GENERAL

[2] COOLING FIN

[3] WATER PUMP

The cooling system consists of a radiator (1), a
centrifugal water pump (4), a suction fan (2) and a
thermostat (3).
The coolant is cooled through the radiator core, and
the fan behind the radiator pulls the cooling air through
the core to improve cooling.
The water pump sucks the coolant from the radiator
or from the cylinder head and forces it into the cylinder
block.
The thermostat opens or closes according to the
coolant temperature, to allow the coolant to flow from the
cylinder block to the radiator while open, or only to the
water pump while closed.
Thermostat's valve
opening temperature
(1) Radiator
(2) Cooling Fan
(3) Thermostat
The cooling fin is set up around the oil passage in the
gear case.
Therefore, the temperature of oil is decreased by the
wind generated by the cooling fan.
(1) Cooling Fin
The water pump is driven by the crankshaft and a V
belt. The rotating impeller (4) in the water pump sucks
the coolant from the radiator and sends it into the water
jacket in the cylinder block.
The mechanical seal (3) prevents the water from
entering the bearing unit (1).
(1) Bearing Unit
(2) Water Pump Body
1-M9
ENGINE
Factory
69.5 to 72.5 °C
specifica-
157.1 to 162.5 °F
tion
(4) Water Pump
(5) Cylinder Head
(6) Cylinder Block
9Y1211108ENM0020US0
9Y1211108ENM0021US0
(3) Mechanical Seal
(4) Impeller
9Y1211108ENM0022US0
KiSC issued 07, 2015 A