Inspection and Verification
| CAUTION | Under no circumstances should the accessory drive belt, tensioner or pulleys be lubricated as potential damage to the belt material and tensioner damping mechanism will occur. Do not apply any fluids or belt dressing to the accessory drive belt or pulleys. |
Scheme 428
Scheme 429
Scheme 430
- Verify the customer concern by operating the system.
- Visually inspect for obvious signs of mechanical damage. VISUAL INSPECTION CHART Mechanical Drive belt cracking/chunking/wear Belt/pulley contamination Incorrectly routed belt Pulley misalignment or excessive pulley runout Loose or mislocated hardware Incorrectly routed power steering tubes (rubbing)
- Eliminate all other non-belt related noises that could cause belt misdiagnosis, such as A/C compressor engagement chirp, power steering cavitations at low temperatures, variable camshaft timing (VCT) tick or generator whine.
- If a concern is found, correct the condition before proceeding to the next step.
- Check the belt for cracks. Up to 15 cracks in a rib over a distance of 100 mm (4.0 in) can be considered acceptable. If cracks exceed this standard, install a new belt.
- The condition of the V-ribbed drive belt should be compared against the illustration and appropriate action taken. Small scattered deposits of rubber material. This is not a concern, therefore, installation of a new belt is not required. Longer deposit areas building up to 50% of the rib height. This is not considered a concern but it can result in excessive noise. If noise is apparent, install a new belt. NOTE: Piling is an excessive buildup in the V-grooves of the belt. Heavy deposits building up along the grooves resulting in a possible noise and belt stability concern. If heavy deposits are apparent, install a new belt.
- There should be no chunks missing from the belt ribs. If the belt shows any evidence of this, install a new accessory drive belt.
- If the concern is not visually evident, verify the symptom and GO to «SYMPTOM CHART»(ref-207553-S42222540692005113000000) .
Symptom Chart
| Condition | Possible Sources | Action |
|---|---|---|
| Accessory drive belt cracking (over 15 cracks in a rib over a distance of 100 mm [4.0 in]) | Accessory drive belt | INSPECT the accessory drive belt. REFER to INSPECTION AND VERIFICATION in this section. INSTALL a new accessory drive belt as necessary. |
| Accessory drive belt chunking | Accessory drive belt | INSPECT the accessory drive belt. REFER to INSPECTION AND VERIFICATION in this section. INSTALL a new accessory drive belt as necessary. |
| Accessory drive belt noise, squeal, chirping or flutter | Defective/worn or incorrect accessory drive belt Misaligned pulley(s) Pulley runout Damaged or worn accessories Fluid contamination of accessory drive belt or pulleys | REFER to COMPONENT TESTS , Drive Belt, Noise/Flutter in this section. REPAIR or INSTALL new parts as necessary. |
| Damaged or worn accessory drive belt tensioner | REFER to COMPONENT TESTS , Belt Tensioner - Mechanical and Belt Tensioner - Dynamics in this section. INSTALL a new accessory drive belt tensioner as necessary. | |
| Premature accessory drive belt wear | Defective accessory drive belt Misaligned pulley(s) Pulley runout Damaged accessories Incorrectly installed drive belt Fluid contamination | REFER to COMPONENT TESTS , Drive Belt Noise/Flutter and Incorrect Drive Belt Installation in this section. REPAIR or INSTALL new parts as necessary. |
| Accessory drive belt does not hold proper tension | Accessory drive belt has excessive cracking or damage | INSPECT the drive belt. REFER to INSPECTION AND VERIFICATION in this section. INSTALL a new drive belt as necessary. |
| Drive belt tensioner worn or damaged | CHECK the drive belt tensioner for damage and correct operation. REFER to the COMPONENT TESTS , Belt Tensioner - Mechanical and Belt Tensioner - Dynamics in this section. INSTALL a new drive belt tensioner as necessary. | |
| Accessory drive component failure | CHECK the accessory drive components. INSTALL new components as necessary. | |
| Accessory drive belt idler pulley bearing failure | INSPECT the accessory drive belt idler pulley for freedom of rotation and damage. INSTALL a new accessory drive belt idler pulley as necessary. |
SYMPTOM CHART