Cummins/Onan — Fan Drive Idler Pulley Assembly - Remove and Install

Repair & overhaul

From a Cummins/Onan owner's manual covering: M11, M1i Series Engines, ps200da. Check it applies to your exact model before use.

Applies to: Cummins/Onan M11 engine

Procedure

1. Loosen the fan idler pulley shaft locknut.
2. Loosen the adjusting mechanism and move the fan idler pulley and fan pulley centers as close as possible.
3. Remove the fan belt.
4. Remove the roll pin and washer from the idler pulley adjusting screw.
5. Remove the locknut and washer from the back of the idler pulley shaft.
6. Remove the adjusting screw.
7. Remove the fan idler pulley from the fan hub support bracket.
8. Install the idler pulley in the fan hub support bracket.
9. Install the washer and locknut on the idler pulley shaft.
10. Install the adjusting screw in the idler pulley shaft.
11. Install and adjust the fan drive belt.
12. Tighten the idler pulley shaft locknut and check belt tension again.

Source: Cummins/Onan owner's manual. Steps and values are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.

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