Kubota WSM STa-30, Workshop Manual

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1-S50
ST
α
-30 · ST
α
-35, WSM ENGINE
Thermostat Valve Opening Temperature
1. Suspend the thermostat in the water by a string with its end
inserted between the valve and seat.
2. Heating the water gradually, read the temperature when the
valve opens and leaves the string.
3. Continue heating and read the temperature when the valve
opens approx. 6 mm (0.236 in.).
4. If the measurement is not within the factory specifications,
replace the thermostat.
W1035849
Radiator Cap Air Leakage
CAUTION
• When removing the radiator cap, wait at least ten minutes
after the engine has stopped and cooled down. Otherwise,
hot water way gush out, scalding nearby people.
1. Set a radiator tester (Code No.: 07909-31551) on the radiator
cap.
2. Apply the specified pressure (88 kPa, 0.9 kgf/cm
2
, 13 psi), and
measure the time for the pressure to fall to 59 kPa (0.6 kgf/cm
2
,
9 psi).
3. If the measurement is less than the factory specification, replace
the radiator cap.
W1036090
Thermostat’s valve
opening temperature
Factory spec.
69.5 to 72.5 °C
157.1 to 162.5 °F
Temperature at which
thermostat completely
opens
Factory spec.
85 °C
185 °F
Pressure falling time Factory spec.
More than 10 seconds for
pressure fall from
88 to 59 kPa
(from 0.9 to 0.6 kgf/cm
2
,
from 13 to 9 psi)
KiSC issued 11, 2006 A