The belt tensioner is the component that tensions the belt, keeping the proper amount of tension on the belt while the it travels around each accessory pulley. When the motor is running, the belt is driven around all of the accessory pulleys by the crankshaft pulley. As the belt is turning around each pulley, the tensioner springs up and down with the movement of the belt to keep the belt properly tensioned. Replace the tensioner once the spring inside of it becomes weak or if it breaks.
Open the hood and locate the tensioner. The tensioner for the 1993 Buick Century 3.3 models is located near the front-center of the engine. The tensioner has a small pulley attached to a spring-loaded arm. The tensioner is also attached to a tensioner bracket that is mounted to the front of the engine.
Rotate the tensioner pulley from the bolt head in the center of the pulley counterclockwise with the ratchet and socket. Pull the belt off the tensioner pulley only. Position the bungee strap around the belt and one of the holes in the water pump pulley so that it does not come out of the other accessory pulleys.
Loosen and remove the bolt from the spring-loaded arm of the tensioner with the ratchet and socket by turning the bolt counterclockwise. Pull the bolt out and place it to the side.
Locate the other six bolts that are holding the tensioner bracket to the front of the engine. Remove the bolts by turning the bolts counterclockwise with the ratchet and socket. Place the bolts in a safe place.
Pull the tensioner and the bracket straight off the front of the engine and place it on the ground.
Position the new tensioner with bracket onto the front of the engine. Screw all of the bolts back into the tensioner bracket, including the bolt that goes into the spring-loaded arm of the tensioner. Tighten each bolt tight with the ratchet and socket. Make sure that each bolt is very tight.
Remove the bungee strap from the belt. Then, rotate the tensioner pulley counterclockwise once more with the ratchet and socket. Slide the belt under the new tensioner pulley. Release the tensioner pulley and it will tighten the belt as it retracts. Remove the ratchet and socket from the pulley and out of the engine compartment.
Inspect the belt to ensure that it is centered under the new tensioner pulley. Then, crank the 1993 Buick Century 3.3 and watch the belt as it travels under the new tensioner pulley to make sure that it does not come off the pulley. Then, turn the engine off and close the hood.
