How to clean the air filter on a grass trimmer and brushcutter

A clean air filter helps your grass trimmer or brushcutter deliver the correct air-fuel mixture, making it easier to start and helping it maintain full power.

Cleaning the filter regularly can also reduce fuel consumption and extend engine life.

Quick answer

Clean the air filter if your machine:

  • Is difficult to start
  • Loses power while cutting
  • Uses more fuel than normal
  • Runs unevenly

Regular cleaning helps prevent these common problems.

Safety first

Before cleaning the air filter:

  • Wear protective gloves
  • Turn off the engine
  • Disconnect the spark plug
  • Allow the engine to cool completely

What you need

  • Soft brush
  • Warm soapy water (foam filter)
  • Clean cloth
  • Air filter oil (if required for your filter type)

Step-by-step: Clean the air filter

Remove the air filter cover

Open the air filter housing according to your model and carefully remove the filter.

Inspect the filter for:

  • Dirt
  • Dust
  • Oil residue
  • Tears or damage

If the filter is damaged, replace it instead of cleaning it.

Clean the air filter

Foam filter

  • Wash in warm soapy water.
  • Rinse thoroughly.
  • Allow to dry completely.

Nylon filter

  • Brush away dirt and debris.
  • Wash if necessary.
  • Allow to dry completely before reinstalling.

Paper filter

  • Tap gently to remove loose dirt.
  • Replace if heavily clogged or damaged.
  • Do not wash with water.

Felt filter

  • Brush away loose dirt.
  • Replace if excessively dirty or damaged.

Apply air filter oil (foam filter only)

If your model uses a foam air filter, apply a small amount of Husqvarna Air Filter Oil after the filter has dried completely.

Spread the oil evenly through the foam and gently squeeze out any excess before reinstalling the filter.

Do not apply air filter oil to paper, nylon or felt filters.

Reinstall the filter

Place the filter back into the housing and make sure it fits correctly.

Secure the air filter cover before starting the machine.

Test your grass trimmer or brushcutter

Start the machine and check that it:

  • Starts easily
  • Idles smoothly
  • Accelerates normally
  • Maintains power while cutting

Common mistakes to avoid

  • Installing a wet foam filter
  • Applying too much air filter oil
  • Using engine oil instead of air filter oil
  • Washing paper filters
  • Reusing damaged filters

How often should you clean the air filter?

Inspect the air filter regularly as part of your routine maintenance.

Clean it more frequently if you work in:

  • Dusty environments
  • Dry conditions
  • Areas with heavy grass or debris

If your trimmer becomes difficult to start or loses power, inspect the air filter before continuing to use the machine.

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