Content .. 262 263 264 265 ..

Jeep Wrangler TJ. Manual - part 264

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.

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.

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

2. Installation damage

2. Replace belt

RIB OR BELT WEAR

1. Pulley misaligned

1. Align pulley(s)

2. Abrasive environment

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

3. Rusted pulley(s)

3. Clean rust from pulley(s)

4. Sharp or jagged pulley groove
tips

4. Replace pulley. Inspect belt.

5. Belt rubber deteriorated

5. Replace belt

BELT SLIPS

1. Belt slipping because of
insufficient tension

1. Adjust tension (2.5L)

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

2. Replace belt and clean pulleys

3. Driven component bearing failure
(seizure)

3. Replace faulty component or
bearing

4. Belt glazed or hardened from
heat and excessive slippage

4. Replace belt.

LONGITUDAL BELT CRACKING

1. Belt has mistracked from pulley
groove

1. Replace belt

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

2. Replace belt

GROOVE JUMPING

(Belt does not maintain correct
position on pulley)

1. Belt tension either too low or too
high

1. Adjust belt tension (2.5L)

2. Pulley(s) not within design
tolerance

2. Replace pulley(s)

3. Foreign object(s) in grooves

3. Remove foreign objects from
grooves

4. Pulley misalignment

4. Align component

5. Belt cordline is broken

5. Replace belt

ACCESSORY DRIVE

7 - 17

DRIVE BELTS - 2.4L (Continued)

CONDITION

POSSIBLE CAUSES

CORRECTION

BELT BROKEN
(Note: Identify and correct problem
before new belt is installed)

1. Excessive tension

1. Replace belt and adjust tension
to specification

2. Tensile member damaged during
belt installation

2. Replace belt

3. Severe misalignment

3. Align pulley(s)

4. Bracket, pulley, or bearing failure

4. Replace defective component
and belt

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

1. Belt slippage

1. Adjust belt tension (2.5L)

2. Bearing noise

2. Locate and repair

3. Belt misalignment

3. Align belt/pulley(s)

4. Belt to pulley mismatch

4. Install correct belt

5. Driven component induced
vibration

5. Locate defective driven
component and repair

6. System resonant frequency
induced vibration

6. Vary belt tension within
specifications.

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

1. Correct rubbing condition

2. Excessive heat causing woven
fabric to age

2. Replace belt

3. Tension sheeting splice has
fractured

3. Replace belt

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

1. Excessive tension

1. Adjust belt tension (2.5L)

2. Belt contacting stationary object

2. Replace belt

3. Pulley(s) out of tolerance

3. Replace pulley

4. Insufficient adhesion between
tensile member and rubber matrix

4. Replace belt and adjust tension
to specifications

7 - 18

ACCESSORY DRIVE

DRIVE BELTS - 2.4L (Continued)

REMOVAL

NOTE: The belt routing schematics are published
from the latest information available at the time of
publication. If anything differs between these sche-
matics and the Belt Routing Label, use the sche-
matics on Belt Routing Label. This label is located
in the engine compartment.

CAUTION: DO NOT LET TENSIONER ARM SNAP
BACK TO THE FREEARM POSITION, SEVERE DAM-
AGE MAY OCCUR TO THE TENSIONER.

Belt tension is not adjustable. Belt adjustment is

maintained by an automatic (spring load) belt ten-
sioner.

(1) Disconnect negative battery cable from battery.
(2) Rotate belt tensioner until it contacts its stop.

Remove belt, then slowly rotate the tensioner into
the freearm position.

REMOVAL

CAUTION: DO NOT LET TENSIONER ARM SNAP
BACK TO THE FREEARM POSITION, SEVERE DAM-
AGE MAY OCCUR TO THE TENSIONER.

Belt tension is not adjustable. Belt adjustment is

maintained by an automatic ( spring load ) belt ten-
sioner.

(1) Disconnect negative battery cable from battery.
(2) Rotate belt tensioner until it contacts its stop.

Remove belt, then slowly rotate the tensioner into
the freearm position. (Fig. 6) or (Fig. 7).

INSTALLATION

Fig. 6 4.0L - Without A/C

1 - GENERATOR PULLEY
2 - IDLER PULLEY
3 - POWER STEERING PUMP PULLEY
4 - WATER PUMP PULLEY
5 - CRANKSHAFT PULLEY
6 - TENSIONER PULLEY

Fig. 7 4.0L Engines - With A/C

1 - GENERATOR PULLEY
2 - IDLER PULLEY
3 - POWER STEERING PUMP PULLEY
4 - AIR CONDITIONING COMPRESSOR PULLEY
5 - CRANKSHAFT PULLEY
6 - WATER PUMP PULLEY
7 - TENSIONER PULLEY

ACCESSORY DRIVE

7 - 19

DRIVE BELTS - 2.4L (Continued)

Belt tension is not adjustable. Belt adjustment is

maintained by an automatic (spring load) belt ten-
sioner.

(1) Check condition of all pulleys.

CAUTION: When installing the serpentine accessory
drive belt, the belt MUST be routed correctly. If not,
the engine may overheat due to the water pump
rotating in the wrong direction.

(2) Install new belt (Fig. 8) or (Fig. 9). Route the

belt around all pulleys except the idler pulley. Rotate
the tensioner arm until it contacts its stop position.
Route the belt around the idler and slowly let the
tensioner rotate into the belt. Make sure the belt is
seated onto all pulleys.

(3) With the drive belt installed, inspect the belt

wear indicator. On 2.4L Engines the gap between the
tang and the housing stop (measurement A) must not
exceed 24 mm (.94 inches).

Fig. 8 Belt Routing 2.4L With A/C

1 - IDLER PULLEY
2 - GENERATOR PULLEY
3 - IDLER PULLEY
4 - POWER STEERING PUMP PULLEY
5 -CRANKSHAFT PULLEY
6 - TENSIONER
7 - A/C COMPRESSOR PULLEY
8 - ACCESSORY DRIVE BELT

Fig. 9 Belt Routing 2.4L Without A/C

1 - IDLER PULLEY
2 - GENERATOR PULLEY
3 - IDLER PULLEY
4 - POWER STEERING PUMP PULLEY
5 -CRANKSHAFT PULLEY
6 - TENSIONER
7 - NON A/C IDLER PULLEY
8 - ACCESSORY DRIVE BELT

7 - 20

ACCESSORY DRIVE

DRIVE BELTS - 2.4L (Continued)

Content .. 262 263 264 265 ..