Inspection
Belt tension should be checked initially between the first 20 to 40 hours of engine operation.
After the initial check, the belt tension should be checked at Every 250 Service Hours or Three Months.
To maximize the engine performance, inspect the belts for wear and for cracking. Replace belts that are worn or damaged.
For applications that require multiple drive belts, replace the belts in matched sets. Replacing only one belt of a matched set will cause the new belt to carry more load because the older belt is stretched. The additional load on the new belt could cause the new belt to break.
If the belts are too loose, vibration causes unnecessary wear on the belts and pulleys. Loose belts may slip enough to cause overheating.
If the belts are too tight, unnecessary stresses are placed on the pulley bearings and on the belts. This may shorten the service life of the components.
Remove the belt guard. Inspect the condition and adjustment of the alternator belts and accessory drive belts (if equipped).
If the belts do not require replacement or adjustment, install the belt guard. If the belts require adjustment or replacement, perform the following procedure to adjust the belt tension.
Adjustment
Alternator Belt
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| Illustration 1 | g00465617 |
Typical illustration (1) Mounting bolt (2) Adjustment bolt (3) Bracket bolts | |
- Slightly loosen mounting bolt (1) and adjusting bolt (2) .
- Move the alternator in order to adjust the belt tension. If the alternator will not adjust, it may be necessary to slightly loosen bracket bolts (3) . Refer to the Specifications, "Belt Tension Chart" topic.
- Tighten adjusting bolt (2) and mounting bolt (1) . Tighten bracket bolts (3) if the bracket bolts were loosened. Refer to the Operation and Maintenance Manual, "Torque Specifications" topic (Maintenance Section).
- Install the belt guard.
If new belts are installed, check the belt tension again after 30 minutes of engine operation at the rated rpm.
Auxiliary Water Pump Belt
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| Illustration 2 | g00465541 |
Typical illustration (1) Mounting bolts (2) Slotted hole | |
- Slightly loosen mounting bolts (1) .
- Adjust the belt tension with a pry bar in slotted hole (2) . Refer to the Specifications, "Belt Tension Chart" topic.
- Tighten mounting bolts (2) . Refer to the Operation and Maintenance Manual, "Torque Specifications" topic (Maintenance Section).
- Install the belt guard.
If new belts are installed, check the belt tension again after 30 minutes of engine operation at the rated rpm.