Cummins/Onan — Areas to inspect include:

For these Cummins/Onan models: MCGBA, MCGCA, MCGDA, MCGDB, MCGGA, MDGDA, MDGDB, MDGDC, MDGDD.

Applies to: Cummins Onan Mcgba, Cummins Onan Mcgca, Cummins Onan Mcgda, Cummins Onan Mcgdb, Cummins Onan Mcgga, Cummins Onan Mdgda, Cummins Onan Mdgdb, Cummins Onan Mdgdc, Cummins Onan Mdgdd

Procedure

1. 5. Run the engine until it is up to operating tem- perature and shut it off.
2. 6. Open the oil drain valve and drain the oil into a suitable container.
3. 7. Remove the oil filter with a filter wrench.
4. 8. Fill the new filter with oil and apply a film of oil to the gasket. Screw the filter on by hand until the gasket just touches the filter head. Tighten the filter another 3/4 turn.
5. 9. Close the oil drain valve and fill with oil to the high mark (H) on the dipstick.
6. 10. Start the engine and check for leaks.
7. 11. Shut off the engine and wait for 10 minutes.

Source: manual:960-0151B Onan MCGBA CA GA DA DB DA DB DC DD Operators Manual (6-2000) .pdf. Figures and steps are as documented; always cross-check against the official manual and any later revisions for your exact serial number before servicing.