149201-0422 ZEXEL 1 468 434 035 BOSCH HYDRAULIC HEAD 1468434035 1492010422

Water Pump
Disassembly of Water Pump
Inspection of Water Pump
If the inspection of the impeller and shaft finds abnormal noise or rough rotation, replace the assembly.
Inspection of impeller and shaft rotation conditionThermostat
Disassembly of Thermostat
Inspection of Thermostat
To test the thermostat operation, immerse the thermostat in a container filled with water, and heat the water while measuring the water temperature. Record the temperature at which the valve starts to open and the temperature at which the valve lift becomes 8 mm [0.3 in.] or more. (a) Stir the water in the container to ensure uniform temperature distribution.(b) When installing the thermostat, be sure to check the valve opening temperature indication stamped on the upper face of the thermostat mounting flange.
Inspection of thermostatThermo Switch
Inspection of Thermo Switch
Immerse the temperature sensor in oil, and measure the resistance while increasing the oil temperature. If the temperature measurement exceeds the standard value significantly, replace the thermo switch.
Since the inspection requires heating of oil to high temperatures, be careful not to get burns or start a fire.
Inspection of thermo switch