An impeller is pressed on one end of the stainless steel drive shaft. The other end of this shaft has internal threads, and a retaining bolt secures the water pump drive gear to the shaft. Two identical roller bearing assemblies are used to carry the shaft.
A rectangular rubber ring, located in a groove in the water pump housing, seals the water pump to the gear case cover. A smaller rectangular rubber ring, located in a groove in the water pump cover, seals the cover to the water pump housing. Engines built before October, 1989, are equipped with rubber O-ring seals on the water pump housing and cover.
An oil seal is located behind the bearing assemblies, and a unitized, spring-loaded, face-type water seal is used behind the impeller. This seal prevents water from leaking down the shaft and into the gear case. It also prevents lubricating oil from entering the cooling system. The water and oil seals cannot be replaced without removing the water pump from the engine.
The pump bearings are lubricated by splash oil through a passage from the front of the pump housing.
|1. Locknut ||12. Drive Shaft |
|2. Gear, Water Pump Drive ||13. Water Seal |
|3. Snap Ring ||14. Impeller |
|4. Bearing Race ||15. Seal Ring, Water Pump Cover |
|5. Roller Bearing, Larger ||16. Bolt, Cover-to-housing |
|6. Spacer Rings (2) ||17. Water Pump Cover |
|7. Roller Bearing, Small ||18. Bolt, Pump Housing to Gear Case Cover |
|8. Bearing Race ||19. Woodruff Key |
|9. Oil Seal ||20. Small Pipe Plug, Water Pump Housing |
|10. Seal Ring, Water Pump Housing ||21. Large Pipe Plug, Water Pump Housing |
|11. Housing, Water Pump ||22. Drain Cock|