Drive Belt Tensioner Diagnosis

WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.

Tools Required

J 23600-B Belt Tension Gage

Run the engine, with no accessories on, until the engine is warmed up.
Shut the engine off.

Fig 1: Reading Drive Belt Tension
Courtesy of GENERAL MOTORS CORP.
Read the drive belt tension using the J 23600-B placed halfway between the generator and the fan pulley. Note the reading and remove the J 23600-B .
Start the engine with the accessories off, and allow the system to stabilize for 15 seconds.
Turn the engine off.

Fig 2: Applying Clockwise Force To Drive Belt Tensioner Pulley Arm
Courtesy of GENERAL MOTORS CORP.
Using a 3/8-inch drive breaker bar, apply clockwise force to the drive belt tensioner pulley arm, Release the force, and immediately take a drive belt tension reading without disturbing drive belt tensioner position.

Fig 3: Applying Counterclockwise Force To Drive Belt Tensioner Pulley Arm
Courtesy of GENERAL MOTORS CORP.
Using the same breaker bar, apply a counterclockwise force to the drive belt tensioner pulley arm, and raise the drive belt tensioner pulley to eliminate all tension. Slowly lower the drive belt tensioner pulley to the drive belt, and take a drive belt tension reading without disturbing the drive belt tensioner position.
Average the three readings. If the average of the three readings is not between 133-222 N (30-50 lb) and the drive belt is not within the drive belt tensioner's operating range, replace the drive belt tensioner. Refer to DRIVE BELT TENSIONER REPLACEMENT .