Drive Belt Tensioner: Testing and Inspection

Accessory Drive Belt Tensioner

Component Test

1. With the engine off, check routing of the accessory drive belt. REFER to Accessory Drive Belt - 2.0L GTDI or REFER to Front End Accessory Drive (FEAD) - Exploded View .

2. Using a suitable, commercially available serpentine belt tensioner release tool, release the tension on the belt and detach the accessory drive belt from the tensioner. Carry out the following tests:

1. Using the release tool, move the tensioner from its relaxed position, through its full stroke and back to the relaxed position to make sure there is no stick, grab or bind, and to make sure that there is tension on the tensioner spring.

2. Rotate the tensioner pulley by hand and check for a binding, contaminated or seized condition.

3. Inspect the area surrounding the accessory drive belt tensioner for oil leaks or contamination and repair any leaks.

3. If the accessory drive belt tensioner does not meet the criteria in the previous step, install a new tensioner. If the accessory drive belt tensioner meets the criteria in the previous step, proceed to testing the tensioner dynamically in the next step.

4. Using a suitable, commercially available serpentine belt tensioner release tool, install the accessory drive belt onto the tensioner. With the engine running, observe the accessory drive belt tensioner movement. The accessory drive tensioner should move (respond) when the A/C clutch cycles (if equipped), or when the engine is accelerated rapidly. If the accessory drive belt tensioner movement is excessive without A/C clutch cycling or engine acceleration, inspect the accessory drive belt for uneven depth of grooves. Excessive uneven depth of grooves in the accessory belt can cause excessive accessory drive belt tensioner movement. To diagnose uneven depth of grooves in the accessory drive belt, install a new accessory drive belt. REFER to Accessory Drive Belt - 2.0L GTDI or REFER to Front End Accessory Drive (FEAD) - Exploded View . If excessive accessory drive belt tensioner movement still exists, install a new accessory drive belt tensioner.

5. If the tensioner is saturated with oil and grease internally, install a new tensioner.