Hey guys,

Here's a nifty walk-through on how to replace the water pump on a '04 TL:

1) Disconnect the negative battery cable.

2) Remove the front splash panel.

3) Drain the cooling system.

4) Remove the timing belt. Inspect the timing belt for any signs of damage or oil and coolant contamination. Replace the timing belt if there is any doubt about its condition.

5) Remove the water pump bolts. Then, remove the water pump and sprocket assembly from the engine block. (refer to this '04 TL water pump diagram)

6) Install the water pump with a new O-ring. Use new bolts and tighten the 6mm mounting bolts evenly to 104 inch lbs. (12 Nm) and the 8mm bolts to 16 ft. lbs. (22 Nm).

7) If removed, install the timing belt rear cover and camshaft pulley.

8) If removed, install the timing belt tensioner.

9) Install or connect the following:
Timing belt and timing belt covers
Accessory drive belts

10) Close the cooling system drain plug. Refill and bleed the cooling system.

11) Connect the negative battery cable.

12) Start the engine, allow it to reach normal operating temperature, check for leaks, and top off as necessary.