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A clean air filter is key to keeping your lawn mower working properly. It stops dust and debris from getting into the engine while allowing that all-important air to flow through.

On the other hand, a dirty air filter leads to decreased fuel efficiency and possible engine problems.

How to clean an air filter on a lawn mower? It will depend on if you have a foam, paper, or hybrid filter.

  • Paper filters can be cleaned by tapping or brushing dust off
  • Foam filters can be washed with dish soap and water
  • Hybrid filters will require both cleaning methods

Even the best lawn mowers need regular maintenance to keep working. After all, you can’t breathe well with a stuffy nose – and your mower’s engine is the same.

 

How Often to Clean a Lawn Mower Air Filter

Male hands replacing air filter on gas powered lawn mower

In general, you should clean a lawn mower air filter every few uses, to prevent a build-up of dirt and debris.

If your mower has disposable paper filters, there’s no need to clean them – you can just replace the filter once it’s gotten too dirty. Do not reuse a disposable paper filter.

For a foam or hybrid air filter, you’ll need to clean the pre-filter or pre-cleaner every 25 operating hours.

Haven’t used your mower in a while (say, over winter) or left it in dusty conditions? Check the air filters before use! You may need to do some quick cleaning and maintenance.

On the other hand, if you regularly hire a lawn mowing service, keep track of how many times they’ve used your mower. You could even ask them to check if your air filter is in good shape!

 

Types of Lawn Mower Air Filters

Typically, there are three kinds of filters for lawn mowers:

  • Foam air filter: These are, well, made of foam! They’re low-maintenance and long-wearing, so are popular filters for mowers. However, they may crumble or discolour with time.
  • Paper air filter: A paper filter will either have several pieces of thin paper or a single layer in accordion folds. It’s more delicate but filters more “accurately.”
  • Hybrid or dual-element: These are a combo of foam and paper filters. The foam element is called a pre-cleaner, then the paper is the main filtration component.

 

Common Signs to Clean Your Mower’s Air Filter

Even without inspecting the air filter itself, there are indications it needs cleaning or replacing! 

These include:

  • Increased gas consumption
  • Lawn mower starts then dies
  • Frequent overheating of the engine
  • Decreased efficiency
  • Black smoke

 

Before Cleaning a Lawn Mower Air Filter

dirty air filter

Always switch off your lawn mower or disconnect the power, then let it cool down completely before doing any work! Exercise proper safety precautions when working on your equipment.

You’ll also want to disconnect the spark plug wire to prevent any accidental starts.

The air filter will usually sit near the top of the engine. Double-check with the manual to make sure.

 

How to Clean a Lawn Mower Paper Air Filter

Start by taking off the shroud or cover – either by removing the screws or unsnapping the fittings.

Gently take out the paper filter, then hold it up to a light source. If there’s little to no light shining through, or it’s completely discoloured, it’s better to replace it outright.

Otherwise, simply tap the filter to loosen the dust and dirt. You can use a soft brush or cloth to carefully wipe the dust off the folds.

You can use a light burst of compressed air to remove stubborn or stuck-on dirt, but be mindful that you don’t tear the paper!

 

How to Clean a Lawn Mower Foam Air Filter

Dirty air filter on lawn mower.

Again, take off the filter cover or shroud. Then lift the foam filter out of its casing.

Check the filter for damage. A dried-out foam filter will crumble when touched, while older filters may be severely discoloured. In this case, it’s better to get a new filter entirely.

You can wash a foam filter in a sink or by using a garden hose. Dish soap works well to remove any grease and dirt.

Rinse the foam until there are no more suds, then squeeze out any excess water. Lay the filter on some paper towels or a dry cloth on a flat surface under the sun. Leave for about an hour to dry.

In the meantime, clean the housing! Avoid using air or solvents, since these could damage the components. A wipe with a microfibre cloth is enough.

Should you oil your lawn mower foam filter? Yes! Once the foam filter is dry, you’ll need to lubricate it. 

Take some engine oil on gloved hands or apply a few drops directly to the filter. Massage the filter to distribute the oil well. 

Pat with another paper towel or rag to remove excess oil, then reinsert the foam air filter into its housing.

 

How to Clean a Hybrid Lawn Mower Filter

Remove the air filter from its housing – remember to get all the parts.

A hybrid or dual-element air filter will have a pre-cleaner made of foam. Inspect it first to see if it’s become brittle or stained, which are signs it needs replacing.

You can wash the pre-cleaner foam in soapy water, or blow it with compressed air.

For the paper filter, use a soft brush or – if the filter can tolerate moisture – wipe it with a damp cloth. You can also try the hand wand on a vacuum cleaner.

Otherwise, if the paper component is too dirty or brittle, simply replace it.

 

How to Clean a Ride-On Mower Air Filter

An old mower at rest on a farm against a beautiful blue and cloudy sky on a farm

Check the manufacturer’s instructions for the air filter’s location in your ride-on mower. You’ll also find steps on how to remove the air filter.

Once you’ve taken the cover and filter out, set aside all the screws and bolts so they won’t get lost. Make sure you cover the air inlet with a clean, dry cloth or some paper towels to prevent dirt from entering.

Take a compressed air canister and use it to clean the filter housing. You can also quickly wipe the housing with a damp cloth to remove dust and dirt.

For paper filters, you can either clean or replace them. For hybrid or foam filters, wash them then let them dry thoroughly.

Remove the cloth from the air inlet, then return the filter to its housing.

 

Why Clean the Air Filter?

Air filters are vital to the health of your lawn mower’s engine! The filter prevents the mower from sucking in dirt and debris while still allowing airflow for fuel combustion.

A clogged or dirty air filter will cut off that airflow, which stops the mower from working properly. This may even prevent your mower from starting.

Regularly cleaning the air filter ensures the engine is taking in clean air, which improves fuel efficiency and prolongs your mower’s lifespan. It also minimises the chances of damage (such as an overheated engine).

 

How to Clean Oil Out of a Lawn Mower Air Filter

Well-used petrol powered lawn mower showing part of its fuel tank and petrol cap. Throttle cables and the air filter box can be seen.

Why is there oil in a lawn mower air filter? It can sometimes get into the air filter if there is excess oil in the engine.

One sign of too much oil is white smoke coming from the lawn mower.

For a foam filter, a good anti-grease dish soap is enough to wash out the engine oil. However, if it gets into a paper filter, you’re better off replacing it with a new one.

 

When to Replace the Air Filter on a Lawn Mower

You should replace a lawn mower’s air filter at least once every mowing season – or about once every 300 hours of operation.

For a paper filter, if the dust is blocking any light from coming through, it’s time to replace it.

On the other hand, crumbling or brittle foam is a sign to replace a foam filter.

How to change an air filter on a lawn mower? Make sure to get one that’s compatible with your brand and model. After that, it’s a simple enough matter to remove the air filter from its casing and insert the new filter into place.

About Author

Jamie Donovan

Jamie is an Australian horticulturalist and landscape designer. He enjoys writing about landscape architecture, garden design and lifestyle topics.

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About Author

Jamie Donovan

Jamie is an Australian horticulturalist and landscape designer. He enjoys writing about landscape architecture, garden design and lifestyle topics.

Share