Drive Belt Tensioner: Testing and Inspection

Auto-tensioner Inspection/Replacement




1. Check whether there is a change in the position of the auto-tensioner before starting the engine and after starting the engine. If there is a change in the position, replace the auto-tensioner.
2. Check for abnormal noise from the tensioner pulley. If abnormal noise is heard, remove the auto-tensioner and replace the tensioner pulley,




3. Turn off the engine. Move the auto-tensioner (A) with the belt tensioner release tool to relieve tension from the alternator-compressor belt (B), then remove the belt.




4. Attach a torque wrench (A) to the pulley bolt.
Measure the torque on the tensioner internal spring by moving the torque wrench in the direction shown. If the measurement is less than the specified value, replace the auto-tensioner.




5. Move the auto-tensioner within its limit with the belt tension release tool in the direction shown, check that the tensioner moves smoothly and check for abnormal noise while moving the tensioner. If the tensioner does not move smoothly or there is abnormal noise, replace the auto-tensioner.




6. Remove the auto-tensioner.




7. If necessary, to remove the pulley bolt, secure the auto-tensioner in a bench vise with soft jaws. To prevent damage to the tensioner, always use soft jaws or equivalent materials between the tensioner and the vise.




8. Remove the pulley bolt (left-hand threads), and replace the tensioner pulley.