To check the water pump, remember it's driven by the accessory drive belt and failure can cause engine damage. Two methods to assess it while installed: check for leaks at weep holes and listen for howling sound or feel shaft wear. For replacement, disconnect battery, drain cooling system, remove drive belt and pulley, then remove water pump bolts and pull it out. Lubricate new pump's O-ring seal and reverse removal steps, tightening all fasteners. Refill cooling system. For other models, disconnect battery, drain system, remove fan, shroud, belt, pulley, and hoses. Remove water pump, clean threads and surfaces, compare to new pump, remove old gasket material. Clean surfaces with lacquer thinner or acetone. Apply RTV sealant to gasket and pump, attach to engine, tighten bolts evenly. Reinstall parts, refill system, check belt tension, and check for leaks.