Cummins/Onan 4.0BGEFA261 OOL / 4.0BGEFA26100L — Checking Engine Oil Level
Maintenance · Engine oil fill cap/dipstick
For the Cummins/Onan 4.0BGEFA261 OOL / 4.0BGEFA26100L, from the Cummins/Onan operator's manual.
Applies to: Cummins/Onan EM (SN5782U1G2RA) engine
Before you start
- Crankcase pressure can blow hot engine oil out the fill opening causing severe burns; always stop the genset before removing the oil fill cap.
Procedure
- Shut off the genset before checking the engine oil level.
- Remove the oil fill cap/dipstick and wipe it clean.
- Screw the oil fill cap back on and remove it to check the oil level on the dipstick.
- Add oil as necessary until the full mark is reached using API Class SG or SH oil of the proper SAE viscosity.
- Do not fill above the Full mark; drain excess oil if too much has been added.
- Screw the oil fill cap on securely to prevent leakage.
Specs & values
- Keep oil level between Full and Add marks
Source: Cummins/Onan operator'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.