MaintainlyHow often should you service a lawn mower?
Service the lawn mower once a year. The commonly recommended range is yearly, before the first cut of spring. A blunt blade tears grass and invites disease, and old fuel is the usual reason a mower will not start in spring. It is seasonal work, best done in spring.
A mower that sat all winter usually fails for the same few reasons: old fuel, a dirty air filter or plug, or a blunt blade. A spring service takes under an hour and gets it ready before the first cut.
Why does servicing your lawn mower matter?
A blunt blade tears grass and invites disease, and old fuel is the usual reason a mower will not start in spring.
What happens if you skip servicing your lawn mower?
A blunt blade tears grass rather than cutting it, leaving ragged, brown tips. Briggs & Stratton says petrol more than 30 days old can break down and stop a mower from starting.
How do you do it?
- Disconnect the power. Remove the spark plug lead on a petrol mower, or the battery or plug on an electric one, before touching the blade.
- Clean the deck. Scrape dried grass from under the deck so air and clippings flow properly. If a petrol mower has to be tilted, keep the spark plug facing up so oil stays in the crankcase.
- Sharpen or replace the blade. A sharp blade cuts cleanly. Balance it after sharpening, or fit a new one.
- Change the oil and filters (petrol). Change the oil at least once a season, clean or replace the air filter, and fit a new spark plug.
- Use fresh fuel (petrol). Drain fuel left over winter and refill with fresh fuel.
- Check the battery (electric). Charge it fully and check cables and the charger for damage.
What does it take?
How do you know servicing your lawn mower is overdue?
- The mower is hard to start
- Ragged, brown grass tips after mowing
- Blue or white smoke, which usually means oil is burning
What do people get wrong?
- Working on the blade without disconnecting the spark plug or battery
- Tipping a petrol mower with the spark plug side down, which lets oil escape the crankcase
When should you stop and call someone?
For a bent crankshaft after hitting something, a mower that still will not start after fresh fuel and a plug, or robot mower faults.
Does this differ in the US, UK, Australia or Canada?
United States
Service in March or April. California has set zero-emission standards for new small engines, phased in by model year; the rules place no requirements on equipment you already own.
United Kingdom
Service in March before the first cut. The HSE says you can keep up to 30 litres of petrol at home, in plastic containers of up to 10 litres or metal containers of up to 20 litres.
Australia
Service in August or September, before spring growth.
Canada
Service in April or May, once the snow has gone.
Frequently asked questions
Why does servicing your lawn mower matter?
A blunt blade tears grass and invites disease, and old fuel is the usual reason a mower will not start in spring.
What happens if you skip servicing your lawn mower?
A blunt blade tears grass rather than cutting it, leaving ragged, brown tips. Briggs & Stratton says petrol more than 30 days old can break down and stop a mower from starting.
Does servicing your lawn mower differ by country?
Universal. Southern hemisphere: August to September. Robot and battery mowers need blade and battery care rather than oil.
When in the year is servicing your lawn mower best done?
This is seasonal work. Plan it for spring, before the weather it protects against arrives.
How we put this together
The figures, intervals and legal points on this page were checked against the sources listed below. The default interval and accepted range are the ones Maintainly uses in its task library. Costs and times are typical ranges and vary by region and by home. Your own manufacturer's instructions come first, and gas, electrical and structural work belongs with a qualified professional. How we research and write.
Sources
- 5 Mower Troubleshooting Tips, Briggs & Stratton. Checked 11 October 2026.
- How To Tune Up Your Lawn Mower, Briggs & Stratton. Checked 11 October 2026.
- Why is White / Blue Smoke Coming from the Engine?, Briggs & Stratton. Checked 11 October 2026.
- 2021 Amendments to the Small Off-Road Engine Regulations, California Air Resources Board. Checked 11 October 2026.
- Storing petrol safely, Health and Safety Executive (HSE). Checked 11 October 2026.
Next steps
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