Water Pump Overhaul

DISASSEMBLE
1. Bearing set screw
2. Impeller






- Use a bench press and a bearing separator.
- Bearing remover J-22912-01
- Bearing unit remover J-38827
- Or equivalents
3. Floating seal
4. Bearing unit
- Heat the pump body in hot water approximately 49°C (120°F) for about 10 minutes.
- Use a bench press and a bearing separator.
- Bearing separator J-22912-01
- Bearing unit remover J-38827
- Or equivalents
- Remove the bearing unit from pump body.
5. Fan hub
- Remove the fan hub from the bearing unit.






- Using a bench press and a bearing separator.
- Bearing separator J-22912-01
- Bearing unit remover J-38827
- Or equivalents
6. Thrower
- Remove the thrower from bearing unit.
7. Impeller seal
- Remove the impeller seal from pump body.
- Attach the impeller seal to the pump body using suitable material and a hammer.
8. Water pump body

INSPECTION AND REPAIR
Inspect the pump housing and hub. The water pump must be replaced if the fan hub threads are damaged, or it there are any visible cracks in the housing or fan hub.

NOTE: Clean the pump housing and fan hub by immersing in solvent cleaner. Rinse thoroughly.

ASSEMBLY
1. Water pump body [8].
- Heat the pump body in hot water approximately 49°C (120°F) for about 10 minutes.
2. Bearing unit [4].






- Press the new bearing unit into place, aligning the bearing set screw hole in the pump body.
3. Bearing set screw [1].
4. Thrower [6].
- Install the new thrower onto the impeller side of the bearing unit.

CAUTIONS:
- Use care not to touch seal surfaces.
- Handle seal edges only.
- Press the new seal unit into with the spring facing toward the impeller.

5. Seal unit [7].
- Press the new seal unit into place, with the spring facing toward the impeller.

CAUTIONS:







- Using impeller seal unit installer.
- Using impeller seal installer J-33829

6. Floating seal [3].






- Install the new floating seal onto the impeller, with the white seal facing out.
7. Fan hub [5].
- Install the fan to press the bearing unit.






- Use bench press and fan hub installer J-38828, or equivalent.






- The distance from the fan hub upper face the pump body lower face shroud must be 99.5 mm (3.9173 inch).
8. Impeller [2].






- Press the impeller into place, flush with the pump body lower face to the impeller blade upper cover the distance should be 4.6 mm (0.181 inch).






- Inspect the fan hub fitting face run-out by turning the fan hub, should be within 0.1 mm (0.0039 inch).
- Check that the fan hub can be rotated smoothly by hand.

NOTES:
1. The fan center and the impeller are installed to the water pump shaft with a press. Never attempt to remove and reinstall the fan center and the impeller a second time. Replace the entire water pump assembly. Removing and reinstalling the fan center and the impeller a second time may result in the breakdown of the water pump during engine operation and subsequent serious overheating problems.
2. The water pump assembly must be replaced whenever the fan center and impeller pressure force falls below 200 kg (441 lbs./1,960 N).
3. Do not attempt to strike the bearing into position with a hammer or similar object. Damage to the bearing will result.