Disconnect the negative battery cable. Drain the coolant into a clean container for reuse.
Remove the serpentine drive belt and the coolant hoses from the water pump.
Remove the water pump pulley bolts and the pulley; the long bolt can be removed through the access hole in the body side rail.
Remove the water pump-to-engine bolts and the pump.
Clean the gasket mounting surfaces. Install a new gasket and pump assembly.
Install the water pump-to-engine mounting bolts and tighten to 89 inch lbs. (10 Nm) for 1990 engines and 126 inch lbs. (15 Nm) for 1991-93 engines.
Connect the coolant hoses to the water pump and install the serpentine drive belt.
Connect the negative battery cable.
Fill cooling system and check for leaks. Start the engine and allow to come to normal operating temperature. Recheck for leaks. When the engine cools down, top off the coolant.