Disconnect the negative battery cable by unscrewing the coupling on the cable to the battery with a screwdriver. Pull the cable away from the battery.
Engage the parking brake, place cinder blocks behind the back wheels and then jack up your Chevy Impala. Use the jack stands to help support the jack.
Discharge the pressure in the radiator by unscrewing the cap. Remove the drain plug located underneath the radiator. Catch the coolant in a resealable container. Clean up any spills.
Use the adjustable wrench to undo the bolts securing the Chevy Impala's accessory drive belt guard. Loosen the bolts on the water pump pulley to get to and remove the accessory drive belt.
Remove the water pump pulley and undo the four bolts securing the water pump to the engine. Clean off the mount after removing the pump, using a shop rag. Inspect the area for cracks.
Put on the New Pump
Squeeze a bead of high temperature automotive sealant on the new water pump and place the new gasket on the pump. Smear some of the sealant around the mounting area on the engine block. Carefully hold the gasket in place on the pump as you mount it on the engine, where you removed the old pump.
Place the new bolts into the holes in the Chevy Impala's water pump in any order, using a torque wrench while the sealant is still wet to obtain a better hold. Tighten to 89 foot pounds of torque.
Replace the rest of the parts in the order you took them off. When installing the pulley bolts, use a torque wrench and 18 foot pounds of torque on each bolt. Inspect the accessory drive belt and replace it, if needed.
Attach the negative battery cable to the post and tighten the screw on the clamp. Replace the drain plug and refill the radiator with the amount and type of coolant specified in your owner's manual.
Move the jack stands, release the jack and remove cinder blocks. Start the Chevy Impala's engine and check for leaks before you shut the hood. Again, clean up any spilled coolant immediately.