Accessory Drive Belt Concerns

WARNING: This page is about a different car, the 2016 Ford Focus. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Do not lubricate the accessory drive belt, accessory drive belt tensioner or idler pulley(s) as potential damage to the accessory drive belt material construction, accessory drive belt tensioner damping mechanism, accessory drive belt tensioner pulley bearing and idler pulley(s) bearing may occur.

Cracking

Accessory drive belts are made from rubber which hardens with time and can develop cracks. As the accessory drive belt runs on the back of some of the pulleys, the cracks are opened up. Small cracks are not considered to be a failure of the accessory drive belt. Only if the crack is deep enough to reach the bottom of the groove to expose the cord or any chunks are found to be missing from the accessory drive belt, is the accessory drive belt condition considered to be unacceptable.

1.

Check the accessory drive belt for cracks. If the damage exceeds the acceptable limit, install a new accessory drive belt. Refer to: Air Conditioning (A/C) Compressor Belt .

Chunking

Chunking describes the condition where long lengths of rubber become detached from the ribs of the accessory drive belt. This is considered to be a failure of the accessory drive belt.

Courtesy of FORD MOTOR COMPANY

2.

Check the accessory drive belt for damage. If any chunks are found to be missing, install a new accessory drive belt. Refer to: Air Conditioning (A/C) Compressor Belt .

Pilling

Pilling is dust that forms in between the ribs of the accessory drive belt from rubber that is worn off the accessory drive belt when it is new. There may also be loose particles left on the accessory drive belt during the manufacturing process. These are worn off and form into small balls of rubber that then get trapped in the grooves of the accessory drive belt. This condition will usually clear itself within 4800 km - 8000 km (3000 miles - 5000 miles) of normal driving.

Courtesy of FORD MOTOR COMPANY

3.

Check the accessory drive belt for pilling. The condition of the accessory drive belt should be compared against the illustration.
- 1.
  
  Small scattered pills. Not considered a concern. No action required.
- 2.
  
  Small scattered pills. Not considered a concern. No action required.
- 3.
  
  Longer pills up to 50% of the rib height. Possible noise concern. INSTALL a new accessory drive belt if noise is apparent. Refer to: Air Conditioning (A/C) Compressor Belt .
- 4.
  
  Longer pills up to 50% of the rib height. Possible noise concern. INSTALL a new accessory drive belt if noise is apparent. Refer to: Air Conditioning (A/C) Compressor Belt .
- 5.
  
  Heavy deposits in the grooves. Possible noise and stability concern. INSTALL a new accessory drive belt. Refer to: Air Conditioning (A/C) Compressor Belt .
- 6.
  
  Heavy deposits in the grooves. Possible noise and stability concern. INSTALL a new accessory drive belt. Refer to: Air Conditioning (A/C) Compressor Belt .

Incorrect fitment

Accessory drive belt noise can be generated by the accessory drive belt being incorrectly fitted on the pulley as shown in the following illustration. Make sure that all the V grooves on the accessory drive belt contact correctly with the pulley.

Courtesy of FORD MOTOR COMPANY

4.

If the cause is not visually evident, verify the symptom and refer to the Symptom Chart.