Generator Maintenance Schedule: What to Do and When
By the Generator Size Calculator Team · Updated · 6 min read
Quick answer: For a Honda EU2000i, a parts retailer's guide lists: check the oil and air filter before each use, change the oil after the first 20 hours and then every six months, clean the air filter after 50 hours or 3 months, adjust the spark plug at 100 hours or six months and replace it yearly or at 200 hours. Generac's air-cooled home standby generators use 200 and 400-hour services. Always check your own manual.
Your manual comes first. The intervals here are examples from one portable model (a Honda EU2000i, as described by a parts retailer) and one standby line (Generac air-cooled home standby). Other brands and models differ, so use your own owner's manual and keep service records, since the warranty may depend on them.
Portable generator schedule
| When | Task |
|---|---|
| Before each use | Check the oil level and the air filter |
| After the first 20 hours | Change the oil (the break-in change) |
| Every six months | Change the oil |
| 50 hours or every 3 months, whichever is first | Clean the air filter |
| 100 hours or six months | Adjust the spark plug and clean the spark arrester |
| Yearly or 200 hours | Replace the spark plug |
These come from a guide to the Honda EU2000i by a Honda parts retailer, which gives 10W30 as the usual oil type, "though this may vary based on climate." It does not say that the numbers are quoted from the manual, so confirm them in yours.
Standby generator schedule
| Run time since last service | Generac air-cooled standby |
|---|---|
| 25 hours total (break-in) | Break-in maintenance |
| 200 hours | Change oil and oil filter, inspect the battery |
| 400 hours | Change oil and oil filter, inspect the battery, replace the air filter, replace the spark plugs |
| Extreme temperatures (below 40°F or above 85°F) | Change oil and oil filter every 100 hours |
Generac says the tasks depend on run hours, time since the last service and the operating environment, and run hours show on the control panel or in its app. See can you run a standby generator continuously.
Why it matters
A generator sits idle most of the year and then has to work for days in an outage. Fresh oil, a clean air filter and a good spark plug are the cheap parts that decide whether it starts. Read the detail pages: oil, spark plug and air filter.
Keep records
- Write down the date and run hours of each service. Generac says to keep maintenance records, as warranty terms require.
- Plan the fuel too. See how long a generator runs on a tank of gas.
- Run it before storm season under a load, to be sure it works. See the generator runtime calculator.
Know how long your generator will run.
Turn the generator off and let it cool before any service. Work outdoors, and never run a generator indoors or in a garage. See how to refuel a generator safely.
Frequently asked questions
How often should a generator be serviced?
It depends on the model. One Honda portable lists oil after 20 hours then every six months, and Generac standby units use 200 and 400-hour services. Check your manual.
What should I check before every use?
The oil level and the air filter, according to the Honda EU2000i guide.
Do I need to keep maintenance records?
Yes. Generac says to keep records, as the warranty terms require.
Is the break-in oil change important?
Yes. The Honda guide lists it after the first 20 hours, and Generac lists a break-in service at 25 hours.
Can I service a generator myself?
Generac says homeowners may do the tasks themselves, though it recommends an authorized service dealer.
Related calculators
Sources: Honda Lawn Parts, Honda EU2000i generator maintenance guide (EU2000i oil, air filter and spark plug intervals; the page does not say it quotes the manual); Generac Support, continuous use maintenance for home standby generators (25, 200 and 400-hour services, 100 hours in extreme temperatures, records and warranty).