Cummins/Onan — Engine Oil Change
Maintenance
From a Cummins/Onan owner's manual covering: Onan P4500iDF, P4500iDF, P4500iDF Inverter. Check it applies to your exact model before use.
Applies to: Cummins/Onan P4500iDF, Cummins/Onan P4500iDF Inverter
Before you start
- Remove the spark plug boot and battery quick-connect plug when working on the generator.
- A new oil drain plug crush washer is recommended at each oil change.
Parts for this job
Part numbers from the service-parts lists for Cummins/Onan P4500iDF, Cummins/Onan P4500iDF Inverter. Verify against your serial number before ordering; some links are affiliate links.
Procedure
- Place the generator on a level surface and allow the engine to cool for several minutes.
- Remove the engine service cover; disconnect the spark plug wire from the spark plug.
- Remove the oil access cover.
- Remove the rubber plug under the oil drain bolt and place an oil pan under the drain hole.
- Using a 10mm wrench, remove the oil drain bolt and allow the oil to drain.
- Install the oil drain plug and tighten securely; install the rubber plug.
- Slowly pour oil into the oil fill opening until level is between the L and H marks.
- Replace the dipstick and hand-tighten.
- Connect the spark plug wire and install the engine service cover.
Tools required
Tool links are Amazon searches (affiliate links); manufacturer special tools may only be available from a dealer.
Specs & values
- Maximum oil capacity: 0.63 US qt (0.60 L)
Full service-parts list: Cummins/Onan P4500iDF →, Cummins/Onan P4500iDF Inverter →
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.