RV Onan Generator Parts Guide

Use this interactive guide to find OEM filters, spark plugs, and maintenance kits by generator model. Expand each section to view compatible parts and maintenance information for your Cummins Onan generator. Keeping up with regular maintenance ensures your generator runs efficiently and reliably while you're on the road.

Cummins Onan RV QG 2800–4000 Series, MicroLite, MicroQuiet Cummins Onan RV QG 5500–7000 Series, Marquis Gold & Platinum Cummins Onan RV QD 3200, 6000/8000, 10000/12500 Series Onan HQD Series Onan Emerald Series Onan Marquis Series Older Onan Diesel & Gasoline Generator Models

Recommended Maintenance Schedule

• Oil & Oil Filter: Replace every 150 hours or annually.
• Air Filter: Clean every 50 hours; replace every 100 hours.
• Spark Plug: Inspect every 100 hours; replace every 300 hours.
• Fuel Filter: Replace every 500 hours or two years.
• Coolant (liquid-cooled models): Replace every 1,000 hours or two years.
• Spark Arrestor: Clean every 150 hours or annually.

Troubleshooting Common Issues

• Fault Code 14: Low oil pressure – check oil level and sensor.
• Fault Code 36: Engine shutdown – inspect fuel supply and temperature.
• Starting Problems: Check battery voltage, wiring, and starter relay.
• Overheating: Clear air vents, inspect cooling fan and coolant levels.

Expert Generator Care Tips

• Run your generator monthly for 30+ minutes under load to prevent fuel and battery issues.
• Use fresh fuel with a stabilizer if storing the RV for more than 30 days.
• Never overload the generator—monitor total wattage draw.
• Drain fuel or add stabilizer before off-season storage; disconnect the battery to prevent drain.

Oil and Maintenance Chemicals