TIP2252 Tech Tip WATER PUMP LEAKAGE – REPLACEMENT REQUIREMENTS ...

WATER PUMP LEAKAGE – REPLACEMENT REQUIREMENTS TIP 2252
NOTE: Coolant stains or deposits on the water pump housing at the location of the drain pocket end
caps should be considered as normal.
Consider this: Coolant stains or deposits on the water pump housing may be considered more
relevant as a need or recommendation for a coolant flush, in comparison to the need to replace a
water pump.
The engine coolant is the lubricant for the water pump. Therefore, coolant will flow between the seal and
the shaft. Under normal operating conditions, the coolant that flows between the seal and shaft will
evaporate before reaching the exterior of the water pump housing. However, it is possible for the coolant
to reach the exterior of the water pump at the location where the shaft extends.
The following are contributing factors that may allow coolant to be seen on the exterior of the water
pump at the location where the shaft extends
• Ambient temperature - cold temperatures preventing the coolant from evaporating before it
reaches the exterior surface of the water pump.
• Ambient temperature - very cold temperatures will cause the materials used in the physical
make-up of the water pump to expand and contract differently.
• Driving routine - short drives with engine shut-off before reaching normal operating
temperature.
NOTE: Coolant stains or deposits observed on the exterior of the water pump housing at the
location of the shaft extension should be considered as normal.
Suggestion:
Standards to determine the necessity to replace leaking water pump:
a. When the complaint is “Engine temperature High”, “Coolant seen on the ground” with the condition of
Coolant seen dripping / leaking from the water pump.
1. Verify the customer’s complaint.
2. Replace the water pump if you confirm the condition.
b. When some other repairs are performed on the vehicle:
1. Verify the “Add-On” repair conditions:
• Coolant stain or deposits on the exterior of the water pump housing.
• The coolant reservoir level is below the ‘L’ low level line (visible on most Toyota models)
• There are no other signs or sources of a coolant leak.
• Previous maintenance service (top up of fluids) was within the last six (6) months
2. If all four “Add-On” repair aspects are met replace the water pump.
If the last maintenance service date is unknown or was performed beyond a period of six (6) months and
the coolant reservoir is below the ‘L’ low level, add coolant and monitor.
Note: In matter of Warranty Standards please consult the WARRANTY Bulletin WAB 2067
NOTE:
Issue of this Tech Tip is to help in the trouble shooting of a specific condition.
If a condition is described, it does not mean it applies to the vehicle you are working on.
IT DOES NOT CONSTITUTE AN AUTHORIZATION FOR REPAIR.
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