RV Generator Maintenance Guide: Step-by-Step Tips to Keep Your Generator Running Right
We’ve been repairing RV generators in the Kansas City area for years. The patterns are always the same. Owner skips maintenance, fuel goes stale, oil turns to sludge, and by the time they call us, a simple service has turned into a major repair bill. This guide is built from what we actually see in the shop — not theory, not a manual rewrite. Real problems, real fixes.
Why RV Generator Maintenance Matters More Than You Think
Your RV generator isn’t like your truck engine. It doesn’t get run every day. It sits for weeks or months between uses, and that downtime is what kills it. Stale fuel gums up carburetors. Oil breaks down and loses its protective qualities. Seals dry out. Connections corrode. Then you fire it up at a campsite and wonder why it’s surging, stalling, or not starting at all.
A solid rv generator maintenance routine prevents about 80% of the failures we see at our shop. We’re talking about basic stuff — oil changes, fuel management, air filters, and exercise runs. None of it is complicated. But if you skip it, you’ll pay for it later.
Here’s the other thing most people don’t realize: generator repairs are expensive. A new carburetor, a control board replacement, or a full fuel system cleaning can run anywhere from $400 to over $1,200 depending on your unit. Compare that to a $30 oil change and a $15 fuel stabilizer, and the math is obvious.
Step-by-Step RV Generator Maintenance Schedule
This is the rv generator maintenance guide schedule we recommend to every customer who rolls through our shop. Follow it, and your generator will last years longer than if you just run it and forget it.
Every 50 Hours of Use (or Once a Season, Whichever Comes First)
– Change the oil and oil filter. Use the weight and type recommended by your generator manufacturer. Onan units typically call for 10W-30 or 15W-40 depending on the model. Don’t guess — check your owner’s manual or call us and we’ll tell you.
– Replace or clean the air filter. A clogged air filter chokes your generator. It runs rich, fouls spark plugs, and burns more fuel than it should. Paper filters get replaced. Foam filters can be washed with mild soap, dried completely, and re-oiled.
– Inspect the spark plug(s). Pull them out and look at the electrode. Light tan or gray is good. Black and sooty means it’s running rich. White means it’s running lean. Replace plugs that are worn, cracked, or fouled. Gap them to spec.
– Check the fuel filter. If your unit has an inline fuel filter, inspect it for discoloration or debris. Replace it if there’s any question.
Every 200–250 Hours of Use
– Replace spark plugs even if they look okay. They degrade over time and a fresh plug makes a noticeable difference in starting and running quality.
– Inspect the exhaust system. Look for leaks, cracks, or carbon buildup at connections. Exhaust leaks on an RV generator are a carbon monoxide risk — this one’s not optional.
– Test the voltage output with a multimeter. Your generator should be putting out steady 120V AC. If it’s fluctuating wildly, you may have an AVR (automatic voltage regulator) issue. That’s a repair best left to a tech who knows RV electrical systems. [INTERNAL LINK: RV electrical and systems repair]
Monthly (Even When You’re Not Using It)
– Run the generator under load for 30 minutes. This is the single most important thing you can do. Running it dry with no load doesn’t count — plug in your AC unit or a space heater so the generator actually works. This burns off moisture, circulates oil, and keeps fuel moving through the system.
– Add fuel stabilizer if the generator will sit for more than two weeks. Stale fuel is the number one killer of RV generators. We see it constantly. A $12 bottle of stabilizer saves you a $500 carb rebuild.
Common RV Generator Problems We See in the Shop
After years of rv generator maintenance and repair work in Kansas City, certain problems show up over and over. Knowing what to watch for helps you catch small issues before they become big ones.
Hard Starting or No Start
Nine times out of ten, this is a fuel issue. Stale gas, a clogged fuel filter, or a gummed-up carburetor. If you stored your RV for winter without stabilizer and the generator won’t fire in the spring, this is almost certainly why. The fix ranges from a simple fuel system flush to a full carburetor rebuild depending on how far gone it is.
Surging or Unstable Power Output
The generator starts but the lights flicker, the AC cycles, or you can hear the RPMs hunting up and down. This is usually a dirty carburetor, a failing AVR, or a governor issue. Sometimes it’s as simple as a clogged air filter restricting airflow. Start with the cheap fixes first.
Generator Runs But Won’t Produce Power
The engine sounds fine but nothing’s coming out of the outlets. This points to the AVR, the capacitor, or the brushes (on brush-type generators). It can also be a tripped breaker on the generator