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Dodge Durango
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Cooling System » Diagnosis and testing
Accessory drive belt diagnosis

VISUAL DIAGNOSIS

When diagnosing serpentine accessory drive belts, small cracks that run across the ribbed surface of the belt from rib to rib (Fig. 23), are considered normal.

These are not a reason to replace the belt. However, cracks running along a rib (not across) are not normal.

Any belt with cracks running along a rib must be replaced (Fig. 23). Also replace the belt if it has excessive wear, frayed cords or severe glazing.

Refer to the Accessory Drive Belt Diagnosis charts for further belt diagnosis.

NOISE DIAGNOSIS

Noises generated by the accessory drive belt are most noticeable at idle. Before replacing a belt to resolve a noise condition, inspect all of the accessory drive pulleys for alignment, glazing, or excessive end play.

Fig. 23 Belt Wear Patterns Fig. 23 Belt Wear Patterns

1 - NORMAL CRACKS BELT OK

2 - NOT NORMAL CRACKS REPLACE BELT

ACCESSORY DRIVE BELT DIAGNOSIS CHART

CONDITION POSSIBLE CAUSES CORRECTION
RIB CHUNKING (One or more ribs has separated from belt body) 1. Foreign objects imbedded in pulley grooves.

2. Installation damage

1. Remove foreign objects from pulley grooves. Replace belt.

2. Replace belt

RIB OR BELT WEAR 1. Pulley misaligned

2. Abrasive environment

3. Rusted pulley(s)

4. Sharp or jagged pulley groove tips

5. Belt rubber deteriorated

1. Align pulley(s)

2. Clean pulley(s). Replace belt if necessary

3. Clean rust from pulley(s)

4. Replace pulley. Inspect belt.

5. Replace belt

BELT SLIPS 1. Belt slipping because of insufficient tension

2. Belt or pulley exposed to substance that has reduced friction (belt dressing, oil, ethylene glycol)

3. Driven component bearing failure (seizure)

4. Belt glazed or hardened from heat and excessive slippage

1. Inspect/Replace tensioner if necessary

2. Replace belt and clean pulleys

3. Replace faulty component or bearing

4. Replace belt.

LONGITUDAL BELT CRACKING 1. Belt has mistracked from pulley groove

2. Pulley groove tip has worn away rubber to tensile member

1. Replace belt

2. Replace belt

9GROOVE JUMPING" (Belt does not maintain correct position on pulley) 1. Incorrect belt tension

2. Pulley(s) not within design tolerance

3. Foreign object(s) in grooves

4. Pulley misalignment

5. Belt cordline is broken

1. Inspect/Replace tensioner if necessary

2. Replace pulley(s)

3. Remove foreign objects from grooves

4. Align component

5. Replace belt

BELT BROKEN (Note: Identify and correct problem before new belt is installed) 1. Incorrect belt tension

2. Tensile member damaged during belt installation

3. Severe misalignment

4. Bracket, pulley, or bearing failure

1. Replace Inspect/Replace tensioner if necessary

2. Replace belt

3. Align pulley(s)

4. Replace defective component and belt

NOISE (Objectionable squeal, squeak, or rumble is heard or felt while drive belt is in operation) 1. Incorrect belt tension

2. Bearing noise

3. Belt misalignment

4. Belt to pulley mismatch

5. Driven component induced vibration

1. Inspect/Replace tensioner if necessary

2. Locate and repair

3. Align belt/pulley(s)

4. Install correct belt

5. Locate defective driven component and repair

TENSION SHEETING FABRIC FAILURE (Woven fabric on outside, circumference of belt has cracked or separated from body of belt) 1. Tension sheeting contacting stationary object

2. Excessive heat causing woven fabric to age

3. Tension sheeting splice has fractured

1. Correct rubbing condition

2. Replace belt

3. Replace belt

CORD EDGE FAILURE (Tensile member exposed at edges of belt or separated from belt body) 1. Incorrect belt tension

2. Belt contacting stationary object

3. Pulley(s) out of tolerance

4. Insufficient adhesion between tensile member and rubber matrix

1. Inspect/Replace tensioner if necessary

2. Replace belt

3. Replace pulley

4. Replace belt

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