Inspect the belts for signs of glazing or cracking. A glazed belt will be perfectly smooth from slippage, while a good belt will have a slight texture of fabric visible. Cracks will usually start at the inner edge of the belt and run outward. All worn or damaged drive belts should be replaced immediately. It is best to replace all drive belts at one time, as a preventive maintenance measure, during this service operation.
CHECKING & ADJUSTING BELT TENSION
Check the drive belts every 6,000 miles for evidence of wear such as cracking or fraying and incorrect tension. Determine the belt tension at a point halfway between the pulleys by pressing on the belt with moderate thumb pressure. The belt should deflect approximately 1 / 4 to 1 / 2 inch at this point. If the deflection is found to be too much or too little, make the necessary adjustment.
Most drive belts are adjusted or replaced by loosening the mounting bolts and the pivot bracket bolt of the driven equipment. That is, the alternator, power steering pump, air pump, or the air conditioner compressor. Some pumps or alternators use an adjusting rod and nut to maintain proper belt adjustment. Some air conditioner compressor belts have an idler pulley which can pivot when the mounting bolt is loosened thus giving access to belt removal or adjustment.
If a belt breaks or shows signs of serious wear, it is a good idea to replace all other drive belts at the same time.
Care should be taken not to pry on the body of a power steering pump, alternator, air pump or air conditioner compressor. Always pry gently under the end frame or use the cut out if provided. Be sure to run the engine for a brief period of time after installing a new drive belt, then recheck the belt for proper tension. Readjust if necessary.
REMOVAL & INSTALLATION
- Loosen the adjustment and pivot bolts on the applicable accessory (alternator, air pump, air conditioning compressor, etc.) from which the belt is to be replaced, then pivot the accessory so that the tension on the drive belt is relieved. Continue moving the accessory until sufficient slack in the belt allows it to be removed from the accessory's pulley.
- Note the routing of the drive belt so that the new belt can be installed correctly on the various pulleys.
- Remove the belt from the engine.
It may be necessary to remove other drive belts before access to the belt needing replacement can be gained.
- Install the new belt over the applicable pulleys. Be sure that the belt is seated correctly on the pulleys.
- Adjust the drive belt tension as described earlier in this section.
- Once the proper tension is achieved, tighten the accessory's adjustment and pivot bolts securely.
- If a new drive belt was installed, readjust the belt tension after 100-200 miles of driving.