Kubota M5040, Workshop Manual

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1-S18
M5040, M6040, M7040, WSM ENGINE
CAUTION
• When removing the radiator cap, wait at least ten minutes after the engine has stopped and cooled down.
Otherwise, hot water may gush out, scalding nearby people.
Radiator Cap Air Leakage
1. Set a radiator tester on the radiator cap.
2. Attach a radiator tester.
Apply the specified pressure of 88 kPa (0.9 kgf/cm
2
, 13 psi).
3. Check if the pressure drop to less than 59 kPa (0.6 kgf/cm
2
, 9 psi)
in 10 seconds.
4. If the pressure is less than the factory specification, replace it.
W1021320
Radiator Water Leakage
1. Pour a specified amount of water into the radiator.
2. Attach a radiator tester.
Increase water pressure to the specified pressure of 137 kPa (1.4
kgf/cm
2
, 20 psi).
3. Check the radiator for water leaks.
4. When water leakage is excessive, replace the radiator. If water
leakage is caused by a small pinhole, correct the radiator with
radiator sealant.
W1072497
Thermostat Valve Opening Temperature
1. Push down the thermostat valve and insert a string between the
valve and the valve seat.
2. Place the thermostat and a thermostat in a container with water
and gradually heat the water.
3. Hold the string to suspend the thermostat in the water. When the
water temperature rises, the thermostat valve will open, allowing
it to fall down from the string.
Read the temperature at this moment on the thermometer.
4. Continue heating the water and read the temperature when the
valve has risen by about 8 mm (0.315 in.).
5. If the measurement is not acceptable, replace the thermostat.
W1071639
Thermostat’s valve
opening temperature
Factory spec.
74.5 to 78.5
°
C
166.1 to 173.3
°
F
Temperature at which
thermostat completely
opens
Factory spec.
90
°
C
194
°
F
KiSC issued 06, 2008 A