The Buick Regal was considered one of the most refined family cars that GM made in 1995. It came with an array of options from custom to grand sport and engine sizes such as the 3.1-liter or the 3.8-liter V-6 engines. The 3.1-liter engine was the most common engine and provided the best fuel economy. The only problem was that the intake manifold gasket would leak coolant into the engine and cause overheating. Replacing the gasket helped to prolong the life of the engine, but if any oil got into the cooling system the water pump would be the next part to fail.
Park the Regal on a flat, solid surface and allow the engine to cool.
Place the wheel chocks around the rear tires. Lift the front of the vehicle by placing the jack under a body pinch weld and place a jack stand under the pinch weld. Repeat for the other side. Open the hood. Remove the radiator cap. Locate the radiator drain plug on the bottom, driver side of the radiator. Remove the drain plug and allow the coolant to drain into the catch pan. Allow the radiator to fully drain.
Take a picture or draw a diagram of the serpentine belt routing to use as a reference. Loosen the water pump pulley bolts with the ratchet and sockets. Remove the belt by placing the ratchet into the square hole on the tensioner arm and lifting up on the tensioner. The tensioner and pulley are located directly below the alternator. Let the belt hang on the engine mount. Remove the water pump pulley bolts and pulley.3
Remove the five water pump housing bolts. Remove the water pump. Clean the water pump mounting surface with the wire brush. Install the new water pump and torque the bolts to 89 inch-pounds with the torque wrench. Install the water pump pulley and bolts until they are hand tight. Install the serpentine belt by routing it in the same pattern and pulling up on the tensioner arm with the ratchet. Torque the pump pulley bolts to 18 foot-pounds.4
Close the radiator drain plug and tighten it by hand. Lower the vehicle. Loosen the two brass cooling system bleeder screws. One is located above the water pump on the heater hose outlet, and the other is on the thermostat housing. Fill the cooling system with a mixture of 50/50 coolant to distilled water. Continue filling until the coolant starts to come out of the bleeder screws. Close the bleeder screw and tighten them slightly until they are sealed. Fill the coolant to the top of the filler neck. Install the radiator cap. Start the engine and allow it to warm up. Watch the temperature gauge and do not allow the engine to overheat. Turn the engine off and allow the engine to cool. Check the engine coolant and top it off if necessary. Fill the coolant reservoir to the full line. Restart the engine and check for leaks.