Cummins/Onan B48 — Spark Plug Maintenance
Maintenance · Ignition System
For the Cummins/Onan B48, from the Cummins/Onan service manual.
Applies to: Cummins/Onan B48, Cummins/Onan B48M engine
Procedure
- Check and regap spark plugs every 100 hours of operation
- Replace spark plugs that show signs of fouling or electrode erosion
- Remove spark plugs
- If plug fouling occurs, clean in suitable solvent and dry thoroughly
- Reinstall clean or new spark plugs
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Spark plug gap: 0.025 in. (0.635 mm)
- Replace interval: 100 hours or when fouled/eroded
Full service-parts list: Cummins/Onan B48 →
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.