How to Adjust the Belt Tension Pulley on an Oldsmobile Achieva

The Oldsmobile Achieva has a singular serpentine belt system to drive all the accessories. The belt is wide and uses a series of grooves that keep alignment of the belt on the similarly grooved pulleys. A belt tensioner is used to apply tension to the belt and to keep a constant tension as it stretches over time. For an Achieva, the belt tensioner is spring-loaded. Belt tensioners have a limited life expectancy on most vehicles and are subjected to fail. One of two things happen--the plastic spring isolator wears out or the pulley bearing fails.

Things You'll Need

• 3/8-inch drive ratchet
• Set of 3/8-inch drive sockets

Instructions

1. Check the tensioner for proper operation to determine the cause of insufficient tension. Insert a ratchet into the access hole in the tensioner arm. Apply tension to the tensioner are with the ratchet and move the tensioner away from the belt.

2. Remove the belt from the tensioner pulley while holding the tensioner away from the belt. Move the tensioner back and forth feeling for any binding. The tensioner should have smooth movement in both directions and have a strong tension opposing the movement of the tensioner.

3. Remove the tensioner, using a socket to remove the singular center bolt. Inspect the back of the tensioner spring area for a worn isolator. Spin the pulley and listen for a bad bearing in the pulley. By turning it slowly by hand, many times a bad bearing can be felt. Replace the proper part. If the plastic is broken, ripped or gone, replace the whole tensioner. If the pulley bearing is bad the pulley and bearing can be replaced independently.

4. Replace the tensioner, making sure that the dowel pin in the rear of the tensioner lines up with the hole in the block. Tighten the center bolt. Use the ratchet to move the tensioner away from the belt, re-install the belt and relieve the tension on the tensioner to allow it to work.