Doosan DX60R Shop Manual page 387

Disassembly of Engine Coolant Pump
1. Remove the thermostat cover (1, Figure 312) Discard the
gasket.
2. Remove the thermostat (2, Figure 312). Discard the O-
ring. Remove the temperature switch (3, Figure 312) and
gasket (4, Figure 312). Discard the gasket.
Cleaning and Inspection
Temperature Switch
1. Check fot proper operation of the temperature switch.
Connect a continuity light or ohmmeter to the temperature
switch. Connect one lead to the terminal of the switch (1,
Figure 313) and the other lead to the metal portion of the
switch (2, Figure 313)
2. Place the temperature
thermometer (3, Figure 313) in engine coolant.
3. Slowly increase temperature of the fluid using an external
heat source.
4. The temperature switch is operating properly if the continuity
light or ohmmeter indicates continuity when the fluid
temperature reaches 225°F - 235°F (107°C - 113°C).
Water Temperature Sensor
1. Inspect the water temperature sensor to make ure that it is
properly operating. As shown in the following figure,
connect an electric resistor to the coupler of the water
temperature sensor (1, Figure 314).
2. Dip the water temperature sensor and an accurate
thermometer (2, Figure 314) into the cooling water.
3. Measure the electric resistance value while slowly raising the
cooling water temperature using an external heat source.
4. The resistance value at each of the following temperatures
is within the permissible range specified, the water
temperature sensor is correctly operating.
Cooling water temperature (°C)
20
80
0.008
Engine
switch and an accurate
Resistance (kΩ)
+0.1
2.45
4
0.318 ± 0.008
(0.1836)
Figure 312
Figure 313
Figure 314
SP001693
Page 207