HYOSUNG 2010 ST7 Service Manual page 178

6-9 COOLING SYSTEM
THERMOSTAT
REMOVAL
Drain engine coolant. (Refer to page 2-25)
Place a rag under the thermostat case.
Remove the thermostat case cap.
Remove the thermostat ①.
INSPECTION
Inspect the thermostat pellet for signs of cracking.
Test the thermostat at the bench for control action, in
the follwing manner.
Pass a string between flange, as shown in the photo-
graph.
Immerse the thermostat in the WATER contained in a
beaker, as shown in the illustration.
Note that the immersed thermostat is in suspension.
Heat the water by placing the beaker on a stove ② and
observe the rising temperature on a thermometer ③.
Read the thermometer just when opening the ther-
mostat.
This reading, which is the temperature level at which
the thermostat valve begins to open, should be within
the standard value.
Thermostat valve
operation temperature
Valve opening
Valve full open
Valve closing
Standard
88 (190 )
100 (212 )
83 (181 )
①
②
③