Service and Repair
WATER PUMP
REMOVAL- 2.7L
NOTE: It is normal for the water pump to weep a small amount of coolant from the primary weep hole (black stain at weep passage). Do not replace the water pump if this condition exists. Replace the water pump if a heavy deposit or a steady flow of engine coolant is evident from the primary weep passage (Fig. 39) and (Fig. 40). This indicates a shaft seal failure and pump must be replaced. Coolant may leak from the secondary weep passage and fill the valley of the engine (Fig. 39) and (Fig. 41). If this condition is found, clean the primary weep passage of debris. Be sure to perform a thorough analysis before replacing water pump.
WARNING: DO NOT REMOVE PRESSURE CAP WITH THE SYSTEM HOT AND PRESSURIZED. SERIOUS BURNS FROM COOLANT CAN RESULT.
Disconnect negative battery cable.
Drain cooling system.
NOTE: The water pump is driven by the primary timing chain.
Remove the timing chain cover, timing chain, and all chain guides.
Remove bolts attaching water pump to block (Fig. 38).
Remove water pump and gasket.
CLEANING
Clean gasket mating surfaces as necessary.
INSPECTION - 2.7L
Inspect and replace the water pump if it has any of the following defects:
Damage or cracks on the pump body.
Coolant leaks: If the shaft seal is leaking, this will be evident by traces of thick deposits of dried glycol running down from the pump primary weep passage (Fig. 39) and (Fig. 40). A thin black stain below the pump primary weep hole/passage is considered normal operation.
Coolant leaks: If the pump primary weep passage is plugged, coolant may come from the secondary weep passage and collect in the valley of the engine. The coolant will eventually run out the back side of the engine (Fig. 39) and (Fig. 41). Leakage from the secondary weep passage may give false indications that core plug(s) may be leaking on the back side of the engine block. If this condition is found, clean the primary weep passage of debris.
Impeller rubs inside of cylinder block.
Excessively loose or rough turning bearing.
NOTE: It is normal for the water pump to weep a small amount of coolant from the primary weep hole (black stain at weep passage). Do not replace the water pump if this condition exists. Replace the water pump if a heavy deposit or a steady flow of engine coolant is evident from the primary weep passage (Fig. 39) and (Fig. 40). This indicates a shaft seal failure and pump must be replaced. Coolant may leak from the secondary weep passage and fill the valley of the engine (Fig. 39) and (Fig. 41). If this condition is found, clean the primary weep passage of debris. Be sure to perform a thorough analysis before replacing water pump.
INSTALLATION - 2.7L
Clean all sealing surfaces.
Install water pump and gasket. Tighten mounting bolts to 12 Nm (105 inch lbs.).
Install timing chain guides, timing chain, and timing chain cover.
Reconnect negative battery cable.
Fill cooling system.
Sunday, September 12th, 2010 AT 11:40 PM
