Once a year or at 12,000 mile intervals, the tension and condition of the drive belts should be checked, and, if necessary, replaced. Loose accessory drive belts can lead to poor engine cooling and diminish alternator, power steering pump, air conditioning compressor or Supercharger output. A belt that is too tight places a severe strain on the accessories' bearings. Inspection of the belt may reveal cracks in the belt ribs. The cracks will not impair belt performance and should not be considered a problem requiring belt replacement. Belts should be replaced if sections of the belt ribs are missing or if the belt is outside the tensioner's operating range. The material used in late-model drive belts is such that the belts do not show wear. Replace belts at most, every three (3) years.
On non-supercharged engines, a single serpentine belt is used to drive all engine accessories formerly driven by multiple drive belts. Supercharged engines use a second belt to drive the supercharger and A/C compressor. The accessories are rigidly mounted with the belt tension maintained automatically by a spring loaded tensioner.
- Run the engine with no accessories on until the engine is warmed up. Shut the engine off. Using a belt tension gauge No. J23600B or equivalent, measure tension between the alternator and power steering pump. Note the reading.
- With the accessories off, start the engine and allow to stabilize for 15 seconds. Turn the engine off. Using an 18mm box-end wrench or socket, apply clockwise force to the tensioner pulley bolt. Release the tension and record the tension.
- Using the 18mm tool, apply counterclockwise force to the tensioner pulley bolt and raise the pulley to eliminate all tension. Slowly lower the pulley to the belt and take a tension reading without disturbing the belt tensioner position.
- Average the three readings. If the average is not between 50-70 lbs. (225-315 N) and the belt is within the tensioner's operating range, replace the belt.
Belt tension is maintained by the automatic tensioner(s) and is not adjustable. The drive belt tensioners can control belt tension over a broad range of belt lengths due to belt stretch and manufacturing tolerances. Limits, though, exist in the tensioners' ability to compensate. Using the tensioners outside their operating range can result in poor belt tension control and damage to the tensioner, belt or accessory. The belt should be replaced when outside the operating range of the tensioner.
REMOVAL & INSTALLATION
- Disconnect the negative battery cable.
- Remove the belt guard or other items as required.
- Take careful note of the belt's routing; it must go back in exactly the same position when installed or things may rotate backwards. Lift or rotate the tensioner using an 18mm box end wrench on the pulley nut.
- Remove the belt.
- Lift the tensioner, and install the belt onto pulleys.
- Double check the routing of the belt(s) for correct routing.