Drive Belt: Description and Operation

NOTE:
- Drive belts with automatic drive belt tensioners do not require adjustment.
- When an accessory drive belt is replaced or reinstalled after a service procedure, the drive belt does not fully seat into pulley grooves until the engine has run for several minutes.

This vehicle is equipped with:
- A V-ribbed serpentine accessory drive belt.
- Automatic drive belt tensioner.

Replacement drive belts should be of the same type as originally installed.

The drive belt condition should be checked:
- at 160,000 km (100,000 miles)
- then every 40,000 km (25,000 miles).

V-RIBBED DRIVE BELT





Drive belt chirp is a regularly occurring chirping noise that occurs due to:
- pulley misalignment.
- excessive pulley runout.

It can be a result of a damaged pulley or an improperly replaced pulley that was not properly aligned.

To correct drive belt chirp:
- Determine the area from which the noise originates.
- Check each of the pulleys in that area with a straightedge to the crankshaft pulley.
- Look for the accessory pulley to be out of position in the fore/aft direction or at an angle to the straightedge.

Drive belt squeal is an intermittent noise that occurs when the drive belt slips on a pulley during certain conditions such as:
- engine start-up.
- rapid engine acceleration.
- A/C clutch engagement.

Drive belt squeal can occur under the following conditions:
- If the A/C discharge pressure goes above 2895 kPa (420 psi); this can occur if:
- the A/C system is overcharged.
- the A/C condenser airflow is blocked.
- the engine cooling fan is not engaging fully at idle.

- If A/C OFF equalized pressure (the common discharge and suction pressure that occurs after several minutes) exceeds 965 kPa (140 psi), which is a rare occurrence at high ambient temperatures with a hot engine, turn A/C OFF for a few seconds and then back ON after engine cooling fan begins to cool condenser.
- If any of the accessories are damaged, have a worn or damaged bearing or internal torsional resistance above normal for any reason; all of the accessories should be rotatable by hand in the unloaded condition. If any are not, the accessory should be inspected.
- If fluids get on the drive belt; this would include power steering fluid, engine coolant, engine oil, air conditioning system lubricant.

If fluids get on the drive belt during service, it is best to clean the drive belt with soap and water, then thoroughly rinse with clean water. The drive belt does not have to be replaced if no apparent damage has occurred.
- A drive belt that is too long will allow the drive belt tensioner arm to go all the way to stop under certain load conditions, which will take tension off the drive belt. If the drive belt tensioner is resting on the stop, replace the drive belt.
- If the drive belt tensioner is worn or damaged.
- The drive belt tensioners are calibrated at the factory. There is no need to check the drive belt tensioner for proper tension unless the spring or other mechanical part of the drive belt tensioner fails.
- If a check is required, do the following:
- Remove the drive belt.
- Rotate the drive belt tensioner from its relaxed position through its full stroke and back to the relaxed position.
- Check to make sure that there is no stick, grab or bind.
- Check that there is tension on the drive belt tensioner spring.