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Lawn Mower Air Filter – Replacement Guide


When it comes to lawn mowers, one of the common problems that people have is a clogged air filter.

While the filter itself is a very simple accessory and can be replaced easily, with a clogged lawn mower air filter the ventilation to the engine is obstructed, this leads to overheating of the engine which can have adverse results.

Primary function of the air filter is to provide filtration of the air intake to the carburetor for the air-fuel mixture being delivered to the spark plug

However the air typically has many particles in it, especially dust and mud which need to be filtered out. If this is not done, they will get accumulated over the engine and damage it. The air filter helps clear the air and send clean air over the engine.

With time, as the filter clears the air, particles start getting accumulated on it and the lawn mower air filter begins to get clogged.

As more and more particles get filtered, the filter starts blocking the air passing over the engine.

The lesser the air, the lesser the ventilation for the engine and hence greater the chance of overheating. If you use the mower for reasonably long periods of time, you would find that it is getting very hot very soon and sometimes even stalls. But if you use it sparingly you may not realize it soon enough.

There are some simple air filter maintenance solutions that will keep your engine performing optimally.

To decide on which is the best solution, you need to first find out what kind of filter does your engine use.

The two most popular filters are paper filter and foam or sponge filter.

  • The paper filters are typically use and throw ones where you need to replace the filter every time it gets clogged.
  • The foam filters can be washed as reused.

Replacing the paper filters

It is a good practice to keep checking the air filter at regular intervals, because sometimes just tapping the filter can clear the trapped dust and you can use the same filter longer.

If the filter looks clogged despite tapping it to get rid of the dust, you must replace it with another on.

While purchasing a replacement, look for the specifications in the owner’s manual or confirm it with the engine’s model number at the store.

Locate the air filter and follow the instructions to remove it from the engine. Typically this involves just unscrewing the holder and pulling the filter out.

Now replace it with the clean filter and screw it back.

Here is the recap of the actions:

  • Unscrew the cover and remove the paper air filter
  • Insert the new filter with pleat facing out
  • Screw the cover back

Replacing the foam filters

As stated earlier, foam filters need not be replaced as frequently as paper filters, they can be cleaned and reused.

The foam filters can be removed from the mowers by following the instructions.

  • Unscrew the cover and removed air filter unit, where you can find the old sponge
  • Once removed, wash it in water with soap Wash it thoroughly till all the clogged particles are cleared.
  • Now let it dry completely till all the moisture is gone.
  • Dip the filter in some engine oil and squeeze out the excess oil from it.
  • Now replace it back into the filter holder. Ensure the lip protrudes over the edge of the unit and screw it back into the machine.

You also can wash old foam with kerosene.

With long hours of operation, sometimes the foam filters are too clogged for even a good wash to clean them, besides regular washing can leave them damaged. In these cases, you can replace them just like you would replace a paper filter.

As you can see, maintenance of air filters in lawn mowers is not a very tough task. The first time could be a bit difficult, especially, if you are not used to handling mechanical devices yourself.

But if you learn this simple step you could save yourself a lot of problems and headache.

Air filters are very important as they have direct bearing on your engine.

An overheated engine is a good indication of clogged filter, if you just clean or replace it, you can avoid an expensive trip to the service center too.