Cooling System; Description - Suzuki DR-Z400S 2001 Service Manual

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COOLING 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
dissipation.
A wax-pellet type thermostat is used to regulate the flow of engine coolant through the radiator. As the
coolant 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 re-
leased to the atmosphere through the radiator core.
Referring to the following illustration, the thermostat is in the closed condition, so that engine coolant recir-
culates 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 Right radiator
4 Left radiator
5 Thermostat