Contents: Static check ⇓ Dynamic check ⇓
Static check
The accessory drive belt tensioner can be checked statically by proceeding as described below.
1. Disconnect the accessory drive belt in the belt tensioner area.
2. Using the special tool, move the belt tensioner from its free position through its full piston stroke and back to the free position to ensure that there is no binding or seizing, and to ensure that the belt tensioner spring is under tension.
3. Rotate the accessory drive belt tensioner pulley and check it for damage, freedom of rotation and correct alignment. Install a new tensioner if necessary.
4. Inspect the area around the accessory drive belt tensioner for grease or other contamination. Repair any leaks before installing a new tensioner. If the belt tensioner is contaminated, do not attempt to clean it, as the damping mechanism located inside may be damaged. Install a new tensioner if necessary.
5. If the accessory drive belt tensioner meets the above criteria, proceed to the dynamic test. If the accessory drive belt tensioner does not meet the above criteria, install a new tensioner.
Dynamic check
The accessory drive belt tensioner can be checked dynamically by following the sequence below.
With the engine running, observe the movement of the belt tensioner. The tensioner should move (respond) when the engine is accelerated sharply or when the A/C clutch is cycled. If the tensioner movement is not constant without engine acceleration or A/C clutch cycling, the pulley or shaft may be warped or out of shape, or the damping mechanism inside the tensioner may be damaged. Excessive accessory drive belt play (uneven groove depth in the accessory drive belt) may be the cause of excessive belt tensioner movement. Check for the problem condition by installing a new accessory drive belt.