Cummins/Onan B43 / B48 — Break-In Procedure
Maintenance · Engine
For the Cummins/Onan B43 / B48, from the Cummins/Onan owner's manual.
Applies to: Cummins/Onan B48, Cummins/Onan B43M engine, Cummins/Onan B48M engine
Before you start
- Using the wrong grade and weight of oil and high engine operating temperatures during break-in can cause engine damage.
Procedure
- Run the engine at half load for the first three hours with intermittent periods of full load.
- Check the oil level at least every five operating hours.
- Add oil to keep it at the proper level but never overfill, which may cause foaming.
- Use the correct oil grade and weight and provide adequate engine cooling.
Full service-parts list: Cummins/Onan B48 →
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.