Your RV generator is your lifeline when you're dry camping or when shore power isn't available. Like any engine, it requires regular maintenance to run reliably — and neglected generators have a way of failing at the worst possible moment. Here's what you need to know to keep yours running.

Exercise Your Generator Regularly

The most common cause of generator failure is lack of use. Generators that sit for months without running develop fuel system problems — varnish buildup in the carburetor, stale fuel, and dried-out seals.

Run your generator under load for at least two hours every month. "Under load" means running your air conditioner or other high-draw appliances — not just idling. Running under load exercises the entire system and keeps fuel moving through the carburetor.

Oil Changes

Generator oil should be changed every 100 hours of operation or once per year, whichever comes first. Check the oil level before every use — generators consume oil, especially in hot weather.

Use the oil viscosity specified in your owner's manual. Most Onan generators specify 15W-40 for warm climates. Running low on oil is one of the fastest ways to destroy a generator engine.

Air Filter

A dirty air filter restricts airflow, causes the engine to run rich, and reduces power output. Inspect the air filter every 50 hours and replace it every 150 hours or annually. In dusty conditions (desert camping, dirt roads), inspect more frequently.

Spark Plugs

Replace spark plugs every 150–200 hours or annually. Worn plugs cause hard starting, rough running, and reduced power. When replacing plugs, check the gap against the specification in your owner's manual.

Fuel System

Fuel filter: Replace annually or every 150 hours. A clogged fuel filter starves the engine and causes surging or shutdown under load.

Carburetor: If your generator has been sitting with fuel in it for more than 30 days, the carburetor may have varnish deposits. Use a fuel stabilizer in the tank whenever the generator will sit for more than two weeks. If the generator surges, hunts, or won't stay running under load, the carburetor likely needs cleaning or rebuilding.

Fuel shutoff: Many generators have a manual fuel shutoff valve. Close it when storing the generator for extended periods to prevent fuel from seeping into the carburetor.

Load Testing

Once per season, run your generator at full rated load for 30 minutes. This means running the air conditioner plus other loads to approach the generator's rated wattage. A generator that runs fine at light load but surges or shuts down under full load has a fuel system or carburetor problem.

Common Generator Problems

Won't start: Check oil level first — most generators have a low-oil shutdown. Check fuel level. Check the choke position. If it cranks but won't fire, suspect the spark plug or fuel system.

Surges or hunts: The engine speed fluctuates up and down. Almost always a carburetor problem — dirty jets or a failing needle valve.

Low power output: Won't run the AC or trips the breaker under load. Could be a carburetor issue, worn brushes in the alternator, or a failing voltage regulator.

Won't start after storage: Stale fuel and varnished carburetor. Drain the fuel, clean or replace the carburetor, and use fresh fuel.

Mobile Generator Service in North Texas

Done Right RV Repair provides mobile generator maintenance and repair throughout North Texas. Our RVTI Master Certified technician comes to your location with the tools and parts to handle most generator repairs on the first visit.

Call us or request service online.