Lawn mower maintenance is essential if you want your lawn mower to do its job properly. And learning how to take care of your lawn mower means it will last longer and cut your grass like it did when it was new. The more you use your mower, the more essential maintenance is.
- Engine oil
- Spark plug
- Fuel filter
- Air filter (optional)
- New belt (if required)
- Tire pump (if needed)
- Socket wrench (to remove spark plug)
- Metal file (or tool for blade sharpening)
Even the best gas lawn mowers and best electric lawn mowers won't stay the best unless you look after them. There are simple regular jobs that you need to do such as cleaning and washing after each use. This will stop the build up of dirt and grass which can affect cutting performance.
Then there are other tasks you need to do around every 12 months such as change the oil, check the battery and sharpen the blade before you store your lawnmower away for the winter. Make sure to check your manufacturer's manual to see what tools and parts you’ll need before following our essential steps for great lawn mower maintenance.
Quick steps: how to maintain your lawn mower
- Change the oil
- Clean/replace the air filter
- Replace the spark plug (every 12 months)
- Clean and sharpen blades
- Stabilize the fuel
- Check the battery
- Check the fuel filter and replace (if needed)
- Check tire pressure
- Service the belts
- Clean the lawn mower
- Winterize the mower
Step by step guide: How to maintain your lawn mower
1. Change the oil
Start the engine to warm up the oil and then switch off to allow the engine to cool down. This will help the oil flow out quicker. Get a pan for the oil to drain into, remove the oil cap and turn the lawn mower onto its side making sure that the oil drains into the pan.
When the oil has drained, put the mower back on all four wheels. Check the manufacturer's manual to see what oil you need and how much. Get a funnel, pour the oil into the engine and replace the oil cap.
2. Clean/replace the air filter
Why clean or replace your air filter? Ryan Patterson, Residential Segment Manager at Husqvarna reveals why: “Regularly replacing the air filter is crucial, especially in dusty conditions. A damaged filter can lead to problems with starting your lawn mower and a noticeable loss of power during use. Therefore, it should be replaced every 3 months or once a season depending on the usage.”
Locate the air filter cover on your lawn mower and take it off. If you have a paper filter, knock the filter on a solid surface to get rid of any dust. If you have a foam filter, remove and wash it in warm soapy water. Squeeze out the water, leave to dry and replace. Make sure it is fitted properly. If the air filter is damaged, worn, or still dirty after cleaning - you need to replace it.
Ryan Patterson is the Residential Segment Manager at Husqvarna's Forest & Garden Division, leading the introduction of outdoor power products to the residential UK market including chainsaws, grass trimmers and the market-leading Husqvarna Automower®. With previous experience in the consumer technology and AV industry, Ryan has worked on bringing a number of award-winning tech products to market for several global tech brands.
3. Replace the spark plug (every 12 months)
If a spark plug gets dirty or damaged it will affect the performance of the lawn mower. Patterson suggests changing annually, “Spark plugs are inexpensive, and we recommend replacing them every year or two.” There are plenty of spark plugs for lawn mowers on Amazon.
To change the spark plug, remove the ignition cable, get the correct size socket for your socket/ torque wrench, place on the spark plug and remove. Get your new spark plug, screw in by hand and tighten with the wrench.
4. Clean and sharpen blades
Make sure that your mower is disconnected from its power supply, unplug or remove the spark plug cap. Give the blade a wipe down with a cloth and warm, soapy water. To get rid of stubborn dirt and debris use a kitchen scrubber/sponge. When finished, wipe clean.
The best way to sharpen the blade is to remove it from the mower. Most have a central bolt, so you will need a wrench and a pair of heavy duty gloves - like the WZQH Leather Work Gloves (Amazon).
Clamp the blade to a flat sturdy surface or place in a vice. Get a fine metal file - like one found in this REXBETI 17Pcs Metal File Set (Amazon) - place at the same angle as the blade edge and push down and forward, repeat until sharp.
5. Stabilize the fuel
Stabilizing the mower's fuel has a host of benefits as Patterson from Husqvarna explains, “Fuel stabilizer removes the need to drain fuel prior to storage by keeping it fresh for around 2 years, and helps prevent build-up with the engine fuel system."
"This is done by following the package directions of the stabilizer and then running the engine for a few minutes to circulate the solution.” Basically you are adding a solution to the fuel that helps the fuel from degrading when in storage.
6. Check the battery
If your lawn mower has a battery you will need to check it’s in good working order. Note that most gas walk-behind mowers don’t have a battery. Locate the battery and use a multimeter to check that the voltage is as expected.
If you have a battery-powered cordless mower, locate the battery and remove it. Most batteries have a battery level indicator on. Simply hold the button to see how much power is left. Recharge if necessary.
7. Check the fuel filter and replace
A fuel filter helps stop dirt and debris in the gas getting to the carburettor and affecting the performance of your lawnmower, so it needs to be replaced regularly. Patterson suggests, “Depending on usage, an annual replacement of the fuel filter should suffice. Without change, this can cause poor engine performance and eventually has the potential to stop the mower from being usable.”
Locate the filter and remove, don't forget to cut the power before you start. There are different types of filters, but it's best to replace unless the manufacturer recommends cleaning.
8. Check tire pressure
You will need to check the tire pressure if you don’t have solid wheels. Patterson explains why: “It’s important to check tire pressure and ensure this is even across all tires."
"Uneven tire pressure can result in an uneven and inconsistent cut.” Invest in a pressure gauge (if you don’t have one) like this AstroAI ATG250 Digital Tire Pressure Gauge (Amazon). Check your manual for recommended pressures.
9. Service the belts
Lawn mower belts link the engine to the blade and need to be looked after as Patterson from Husqvarna reveals: “Mower belts should be checked regularly. There is no specific time on how often these should be replaced as their lifetime depends on operating conditions. It's important to ensure belts are not worn or damaged and are correctly tensioned.”
But they are not that easy to install and will differ from model to model. Check the manufacturer’s manual for details. Alternatively, visit a local dealer to get the job done.
10. Clean the lawn mower
Ideally you need to clean your lawn mower after every use. A quick brush down with a stiff brush and a wash with water and a cloth, or use a garden hose. Remember to make sure that the power source is off before you start. If you don’t clean after every use, grass and dirt will build up on the inside of the mower and the blade, which will affect the performance of your lawn mower.
If there is a buildup of dirt and grass, dampen and leave for five minutes before getting a plastic scraper like this Cotarba Durable Plastic Scraper Set (Amazon). You don't want a sharp edge as this can damage the mower. Finally, give a spray with WD-40 to help protect and lubricate.
11. Winterize your lawn mower
When the grass cutting season comes to a close, you need to think about getting it ready to put it into storage until your yard needs another trim. Before you start, remember to disconnect your spark plug or power supply.
The first step is to empty the tank and get rid of/store any remaining gas. Then think about draining the oil, removing the blade to clean and sharpen, removing/changing the air filter, removing the battery and making sure to give it a good clean. A lot of these tasks can be part of the annual service you should be giving your lawn mower.
Finally, store your lawn mower in a dry place away from the elements such as a shed or garage. If you don't have either you can store in your basement, but keep away from furnaces and any naked flames.
How to maintain your lawn mower: FAQs
How often should a lawn mower be serviced?
This will depend on how often you use your mower. But, as a general rule for home use, once as year should be enough as Ryan Patterson, Residential Segment Manager at Husqvarna explains.
“For standard use, petrol lawn mowers should be serviced at least every 12 months, however if used more frequently then we would suggest servicing blades every 25 – 30 hours of use. Oil changes every 30 hours or so and all other moving parts every 50 hours. Battery lawn mowers should also be serviced once a year and follow a similar logic”.
Should I wash my lawn mower after every use?
It might seem like a chore, but keeping your lawn mower clean will go a long way to keeping it running as its best. If you allow a build up of dirt and grass it will affect performance. Patterson says you need to "make sure you clean it after every use and always double-check that your lawn mower is clean before you start using it”.
How often should I oil my lawn mower?
You can check your oil regularly by removing the dipstick, giving it a wipe and checking the current level. If it is low you can add more oil to get it back to the correct level. But you will need to change the oil at some point.
Patterson recommends that you “change the oil either after every 25 hours of operation or at the end of each season. In particularly dusty or dirty conditions, more frequent oil changes may be necessary.”
Where to buy spare lawn mower parts
If you are looking to replace parts of your lawn mower, your first stop would be the manufacturer's website to see if they sell official parts or have any official suppliers. For example, if you have a Husqvarna lawn mower you can visit their site and use the store locator to search for a location near you that does servicing.
You can go online and visit specialist lawn mower sites like Lawn Mower Parts World or MTD to search for suitable parts. Your local Home Depot might sell what you are looking for, and of course there is always Amazon which sells a whole range of lawn mower parts.
Maintaining your lawn mower is essential for keeping it in good working order. You need to look after it otherwise it won’t work as effectively and won’t last as long as it should.
There are a few simple steps that you can take throughout the cutting season and some essential maintenance that you will need to do around every 12 months that you will find in the steps above. Follow these and your lawn mower will be your friend for years to come.