Cummins/Onan 4.0 BF-1R/9500 — Flywheel Removal
Repair & overhaul
For the Cummins/Onan 4.0 BF-1R/9500, from the Cummins/Onan service manual.
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Before you start
- Do not remove the screw completely since it acts as a restrainer when the flywheel snaps loose.
- Do not use a screwdriver or pry behind the flywheel against the gear case.
Procedure
- Turn the flywheel mounting screw outward about two turns (do not remove completely).
- Install a puller bar on the flywheel.
- Turn the puller bar bolts in alternately until the wheel snaps loose on the shaft.
- Unscrew the puller, remove the mounting screw and washer, and pull the flywheel off.
- Use a steel key for mounting the flywheel.
Tools required
- flywheel puller/puller bar Amazon
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Source: Cummins/Onan service 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.