6.2.4.
Thermostat
•
General descriptions and main data
The thermostat maintains a constant
temperature of coolant (90 ~ 95 °C)
and improves thermal efficiency of the
engine by preventing heat loss.
Namely, when the temperature of
coolant is low, the thermostat valve is
closed to make the coolant bypass to
directly enter the water pump; when
the coolant temperature rises to open
wide the thermostat valve, the bypass
circuit is closed and the water pas-
sage to the radiator is opened so that
the coolant is forced to flow into the
radiator.
NOTE :
There are 2 kinds of thermostats according to surrounding and operating conditions.
One is named by 71 °C type and the other is 83 °C.
•
Inspecting
(1) Check the wax pallet and spring
for damage.
(2) Put the thermostat in a container
of water, then heat the water slow-
ly and check temperature with a
thermometer. If the valve lift is 0.1
mm (starting to open) at tempera-
ture of 83 °C and 8 mm or more
(opening wide) at temperature of
95 °C, the thermostat is normal.
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MAINTENANCE OF MAJOR COMPONENTS