M11 Plus Series Engines Operation and Maintenance Manual – 008-002   Drive Belt, Cooling Fan

Consult the vehicle manufacture for non-Cummins fan hub installations.

Do not adjust belt tension to full value with the adjusting screw. Belt tension can increase when the locknut is tightened and cause reduced belt and bearing life.

Loosen the idler pulley shaft locknut.

Use belt tension gauge, Part Number ST-1293, or equivalent, to adjust the belt to the correct tension. Refer to Procedure 018-005 (Drive Belt Tension) in Section V for correct belt tension.

Tighten the idler pulley shaft locknut.

Check the belt tension again to make the belt is not to tight.

Loosen the fan idler pulley shaft locknut.

Turn the adjusting screw counterclockwise to release the belt tension.

Move the fan idler pulley and fan pulley centers as close as possible. The belt can then be removed without excessive force.

Inspect the belt for:

• Cracks
• Glazing
• Tears or cuts
• Excessive wear.

Inspect the fan idler pulley and the fan drive pulley for cracks or broken grooves.

Replace the pulleys if necessary. Refer to a Cummins Authorized Repair Location.

Inspect pulley alignment.

Replace the fan idler pulley and fan hub pulley if they are not in alignment. Refer to a Cummins Authorized Repair Location.

CAUTION  To prevent damage to the pulley and new belt, do not roll the belt over the pulley or pry it on with a tool.

Install a new fan belt on the pulleys.

Use belt tension gauge, Part Number ST-1293, or equivalent to measure the belt tension. Refer to Procedure 018-005 (Drive Belt Tension) in Section V.

Turn the adjusting screw to adjust the belt tension.

NOTE: A belt is considered used if it has been in operation 10 minutes or longer. If used belt tension is below the minimum value, tighten the belt to the maximum value. Replace the belt if it will not maintain correct tension.

Tighten the idler pulley shaft locknut.

Inspect pulley alignment.

Pulley misalignment must not exceed 6 mm for each meter [1/16 inch for each 12 inches] of distance between the pulley centers.