Thermostat - SSANGYONG 2004 Rexton 2.7XDi Workshop Manual

DI06-7

Thermostat

A wax pellet-type thermostat controls the flow of the engine
coolant through the engine cooling system. The thermostat is
mounted in the thermostat housing to the front of the cylinder
head. The thermostat stops the flow of the engine coolant
from the engine to the radiator to provide faster warm-up, and
to regulate the coolant temperature. The thermostat remains
closed while the engine coolant is cold, preventing circulation
of the engine coolant through the radiator. At this point, the
engine coolant is allowed to circulate only throughout the heater
core to warm it quickly and evenly. As the engine warms, the
thermostat opens. This allows the engine coolant to flow
Y220_06008
through the radiator where the heat is dissipated. This open-
ing and closing of the thermostat permits enough engine cool-
ant to enter the radiator to keep the engine within proper en-
gine temperature operating limits. The wax pellet in the ther-
mostat is hermetically sealed in a metal case. The wax ele-
ment of the thermostat expands when it is heated and con-
tracts when it is cooled. As the vehicle is driven and the en-
gine warms, the engine coolant temperature increases. When
the engine coolant reaches a specified temperature, the wax
pellet element in the thermostat expands and exerts pressure
against the metal case, forcing the valve open. This allows the
engine coolant to flow through the engine cooling system and
cool the engine. As the wax pellet cools, the contraction al-
lows a spring to close the valve.
The thermostat begins to open at 85°C and is fully open at
100°C. The thermostat closes at 85°C.
Operating
Thermostat Opening Value (mm)
Temperature (°C)
Begins to open 85°C 0.1 mm
Fully open 100°C 8 mm
COOLING SYSTEM
CHANGED BY
DI ENG SM - 2004.4 EFFECTIVE DATE
AFFECTED VIN