Ownership guide · Maintenance
Keep your generator
ready when you need it.
A generator that sits unused for months and then fails during a storm is worse than no generator at all. This guide covers everything you need to do — and when — to keep yours reliable for 20+ years.
01 — Why it matters
Generators fail when they sit idle.
The most common reason a generator won't start during an outage isn't mechanical failure — it's neglect. Stale fuel, a dead battery, gummed-up carburetors, and degraded oil are all entirely preventable with a simple routine. Most of these tasks take under 30 minutes.
02 — Maintenance schedule
The complete maintenance checklist.
Use this as your annual maintenance reference. Bookmark it, print it, or save it — whatever gets it done.
| Task | Frequency | Notes |
|---|---|---|
| Run the generator under load | Monthly | Run for 20–30 minutes with a real load (lights, appliance). Standby units do this automatically via weekly self-test. |
| Check oil level | Monthly / before each use | Check when cold. Add manufacturer-specified oil if below minimum. Never overfill. |
| Inspect air filter | Every 3 months | Clean foam filters with soap and water. Replace paper filters if gray or clogged. Never run without a filter. |
| Check fuel system (portable) | Every 3 months | Drain or stabilize gasoline after 30 days. Use fresh fuel each season. Stale gas is the #1 cause of no-start. |
| Test battery (standby) | Every 6 months | Check battery voltage and terminal connections. Replace every 2–3 years regardless of condition. |
| Change oil and filter | Annually or every 100 hrs | Use manufacturer-specified oil weight. Change more frequently in dusty or hot conditions. |
| Replace spark plugs | Annually or every 100 hrs | Check gap before installing. Fouled plugs cause hard starts and rough running. |
| Clean or replace fuel filter | Annually | Especially important if you've run the generator on stale or contaminated fuel. |
| Inspect coolant (liquid-cooled units) | Annually | Check level and condition. Replace coolant every 2 years. Check hoses for cracks. |
| Inspect exhaust system | Annually | Look for cracks, holes, or rust in the exhaust pipe and muffler. A damaged exhaust is a CO risk. |
| Test transfer switch (standby) | Annually | Simulate an outage and confirm the ATS transfers and restores power correctly. |
| Professional tune-up | Every 2 years | A licensed technician can catch issues — worn brushes, capacitor degradation, valve wear — before they cause a failure. |
03 — What most people get wrong
Six maintenance mistakes that cause failures.
Storing with old gasoline
Gasoline degrades in 30 days without stabilizer. A carburetor full of varnished fuel is the single most common reason a generator won't start. Always run the carb dry or add stabilizer before storage.
Never running it under load
Idling without a load lets carbon build up and doesn't condition the oil. Connect a real load — lights, a space heater — when you run your monthly test.
Ignoring the battery (standby)
A standby generator with a dead battery won't auto-start — which defeats the entire purpose. Check the battery voltage twice a year and replace on schedule, not after failure.
Skipping oil changes
Generator engines run hard. Degraded oil accelerates wear on bearings and pistons. Change oil annually at minimum, or every 100 hours of run time — whichever comes first.
Running in rain without cover
Portable generators are not waterproof. Running one in rain can cause electrocution or engine damage. Use a canopy specifically designed for generators — not a tarp draped over the unit.
Delaying professional service
Most generator problems give warning signs — longer crank times, rough idle, unusual smell. Don't wait for a full failure. A preventive tune-up costs far less than an emergency repair.
04 — Safety
Carbon monoxide kills without warning.
Never run a generator indoors, in a garage, or within 20 feet of a window or door.
Generator exhaust contains carbon monoxide (CO) — a colorless, odorless gas that can be fatal within minutes. CO detectors do not eliminate the risk of running a generator in an enclosed space; they only alert you after dangerous levels are already present. Always operate outdoors, downwind from any opening into the home.
05 — Professional service
When to call a technician.
Most routine maintenance is DIY-friendly. These situations call for a professional.
Annual tune-up (standby)
Standby generators benefit from a yearly inspection by a certified technician — especially transfer switch testing, load bank testing, and brush/AVR inspection on larger units.
Unusual noises or smoke
Knocking, backfiring, or visible smoke during operation signals a mechanical problem. Stop the generator and have it inspected before running it again.
Electrical output issues
If voltage is fluctuating, appliances are tripping, or the generator won't hold a load, the AVR, capacitor, or stator may need attention — don't DIY electrical diagnostics.
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