Drive Belt: Service and Repair

REMOVAL





Fig. 75

Drive belts on both 3.9L and 5.9L engines are equipped with a spring loaded automatic belt tensioner (Fig. 75). This belt tensioner will be used on all belt configurations, such as with or without power steering or air conditioning. For more information, refer to Drive Belt Tensioner, 3.9/5.9L Engines.

1. Attach a socket/wrench to pulley mounting bolt of automatic tensioner.
2. Rotate tensioner assembly clockwise (as viewed from front) until tension has been relieved from belt.
3. Remove belt from idler pulley first.
4. Remove belt from vehicle.


INSTALLATION





Fig. 76

CAUTION: When installing serpentine accessory drive belt, the belt must be routed correctly. If not, engine may overheat due to water pump rotating in wrong direction. Refer to (Fig. 76) for correct 3.9L/5.9L engine belt routing. The correct belt with correct length must be used.

1. Position drive belt over all pulleys except idler pulley. This pulley is located between generator and A/C compressor.
2. Attach a socket/wrench to pulley mounting bolt of automatic tensioner.
3. Rotate socket/wrench clockwise. Place belt over idler pulley. Let tensioner rotate back into place. Remove wrench. Be sure belt is properly seated on all pulleys.
4. Check belt indexing marks. Refer to the Drive Belt Tensioner, 3.9L/5.9L Engine for more belt information.
The tensioner is equipped with an indexing arrow on back of tensioner and an indexing mark on tensioner housing. If a new belt is being installed, arrow must be within approximately 3 mm (1/8 inch) of indexing mark. Belt is considered new if it has been used 15 minutes or less. If this specification cannot be met, check for:
- The wrong belt being installed (incorrect length/ width)
- Worn bearings on an engine accessory (A/C compressor, power steering pump, water pump, idler pulley or generator)
- A pulley on an engine accessory being loose
- Misalignment of an engine accessory
- Belt incorrectly routed.
A used belt should be replaced if tensioner indexing arrow has moved beyond the minimum tension mark.