The Oldsmobile Alero model vehicles that came with the 2.2-liter engines were manufactured between 1999 and 2004 by General Motors. The 2.2 engine came equipped with a serpentine belt that operates all of the engine accessories such as the alternator, air-conditioner, power steering pump and the water pump. The serpentine belt is tensioned by a spring-loaded belt tensioner. Over time, the spring inside of the tensioner will weaken or break. The main sign of a damaged belt tensioner is a loose serpentine belt. Replace the tensioner immediately after noticing the damage.
Park the Oldsmobile Alero on a level surface and in a safe work area. Engage the parking brake. Open and raise the hood and wait about an hour for the engine to completely cool down. Once the engine has cooled down, remove the negative battery cable from the negative battery post with an adjustable wrench and set it out of the way.
Inspect the top of the plastic radiator shroud for the serpentine belt routing directions. The diagram is stamped to the top of the radiator shroud and it will be a picture that outlines the routing directions of the serpentine belt. The diagram will be needed in case the belt slips out of any of the accessory pulleys.
Locate the belt tensioner on the front of the engine. The tensioner is mounted to the front middle portion of the engine between the power steering pump and the crankshaft. Place a socket and a breaker bar onto the bolt head in the middle of the tensioner pulley. Turn the breaker bar clockwise with one hand to release the tension from the belt. Reach down with the other hand and slide the belt off of the tensioner pulley. Slowly release the breaker bar and the tensioner will retract until it stops. Once the tensioner stops retracting, remove the breaker bar and socket from the tensioner pulley bolt head.
Hook one end of a bungee cord to the belt near the tensioner. Hook the other end of the bungee cord through the holes on the power steering pump to hold the belt up and to prevent the belt from slipping out of the the pulleys.
Locate the single bolt head on the front middle section of the spring-loaded arm of the tensioner. Loosen and remove the single bolt with a ratchet and a socket. Place the bolt in a safe area. Pull the old tensioner straight off the front of the engine. Match the old tensioner to the new tensioner to ensure that the new tensioner is the proper size.
Position the new belt tensioner in the same location as the old tensioner and line up the mounting bolt hole on the tensioner with the hole on the front of the engine. Screw the tensioner mounting bolt through the center of the tensioner. Tighten the tensioner mounting bolt down snug with the ratchet and socket. Torque the tensioner bolt in a range of 30 to 40 foot-pounds with a torque wrench and a socket.
Place the socket and breaker bar onto the bolt head of the new tensioner pulley. Turn the breaker bar clockwise with one hand and remove the bungee cord from the belt with the other hand. Slide the belt under the new tensioner pulley and slowly release the breaker bar. As the new tensioner is retracting, the tensioner pulley will pull the belt to the proper tension. Finish removing the bungee cord from the engine compartment. Inspect the belt to ensure that it is seated inside all of the accessory pulleys.
Reconnect the negative battery cable to the negative battery post and tighten the cable with the adjustable wrench. Crank the engine for about 15 to 30 seconds. Inspect the belt to ensure that it remains inside of each pulley. Also inspect the new tensioner pulley to ensure that it is rolling freely and moving up and down with no restrictions. Turn the engine off and shut the hood.
