Pacifica, 2003-2005

Removal & Installation


3.5L Engine

The water pump has a die cast aluminum body and a stamped steel impeller. It bolts directly to the chain case cover using an O-ring for sealing. It is driven by the back side of the serpentine belt.

It is normal for a small amount of coolant to drip from the weep hole located on the water pump body (small black spot). If this condition exists, DO NOT replace the water pump. Only replace the water pump if a heavy deposit or steady flow of brown/green coolant is visible on the water pump body from the weep hole, which would indicate shaft seal failure. Before replacing the water pump, be sure to perform a thorough inspection. A defective pump will not be able to circulate heated coolant through the long heater hose.

  1. Before servicing the vehicle, refer to the Precautions section.
  3. Drain the cooling system.
    Do not use pliers to open the plastic drain.

  5. Remove or disconnect the following:
    It is good practice to turn the crankshaft until the No. 1 cylinder is at Top Dead Center (TDC) of its compression stroke (firing position).

    Negative battery cable
    Coolant recovery cap and open the thermostat bleed valve
    Timing belt

    Water pump mounting bolts and pump. Discard the O-ring seal.

  7. Clean the gasket sealing surfaces, being careful not to scratch the aluminum surfaces.

    Click image to see an enlarged view

    Fig. Location of the water pump mounting bolts-3.5L engine

    Location of the water pump mounting bolts-3.5L engine

To install:

  1. Install or connect the following:
    Rotate the pump and check for freedom of movement.

    New O-ring and coat with dielectric grease prior to installation
    Water pump with a new O-ring. Torque the water pump-to-engine bolts to 105 inch lbs. (12 Nm).

    Timing belt

  3. Fill the cooling system.
  5. Reconnect the negative battery cable. Start the engine and allow it to reach normal operating temperatures.
  7. Check the cooling system for leaks and correct coolant level.