Remove the cable which was connected to the negative terminal of the battery. Flush out the cooling system as a whole and keep the coolant, if the coolant is comparatively new or good, and do note the below mentioned Caution. Detach the drive belts, and for 2.4 L engines, unscrew the drivebelt tensioner and idler pulley together with the bracket. Take out the alternator, and for the 1.8L engines, you need to take out the water pump pulley bolts and the pulley-loosening while holding the water pump pulley and then remove the three mounting bolts. Take off the drivebelt tensioner and for 2.4L engines ,remove the crankshaft pulley if there is. Take out the bolts and pull off the water pump from the engine and inspect the impellers for signs of rot and filing off fins. Free the bolt threads and threaded holes in the engine for corrosion and sealants. Ascertain that the new pump corresponds to the old one in all factors by comparing them to each other. Clean all old gasket sealant and O-ring from the engine block and then clean both the surfaces of the mating engine and the new water pump by wiping on brake system cleaner. Coat lightly with RTV sealant the O-ring groove of the new pump, and then place carefully a new O-ring into the groove. Screw the bolts in the pump and fix it to the engine with finger tightened bolts the bolt threads should be coated with RTV sealant and the dowel pins must be in original position. Loosen some of the bolts and then process of tightening should be done gradually to the recommended torque but not exceeding this as this may cause distortion of the pump. Replace all components that were dismantled for the access to the pump, fill the cooling system, and adjust drivebelt tightness. Last but not the least, connect the battery, start the engine and check for any kinds of leakages.