Diesel Data: Automotive Repair

Water Pump: Testing and Inspection

Water Pump

Inspection
1. Check the water pump bearing for smooth rotation.
2. Check the water pump pulley for abnormalities.
3. Using a dial gauge, measure the impeller runout in thrust direction while rotating the pulley.
^ "Thrust" runout limit: 0.5 mm (0.020 inch)





4. Check the clearance between impeller and pump case.
^ Clearance between impeller and pump case:
^ Standard 0.5 - 0.7 mm (0.020 - 0.028 inch)





5. After water pump installation, check the pulley shaft for engine coolant leaks. If leaks are noted, replace the water pump assembly.