How do I clean the air filter on my lawn mower?

Keeping the air filter on your lawn mower clean is an important part of regular maintenance that will help keep your mower running smoothly. A dirty air filter can restrict airflow into the carburetor, which can cause poor performance, lack of power, or hard starting. Fortunately, cleaning the air filter is a quick and simple task that you can easily do yourself.

When to Clean the Air Filter

As a general rule, you should check and clean the air filter on your lawn mower after every 25 hours of use. If you routinely mow in dusty or dirty conditions, you may need to clean the filter more frequently. Here are some signs that indicate it’s time to service the air filter:

  • The engine is running rough, sputtering, or lacks power
  • The mower is using more gas than usual
  • The engine is hard to start
  • You notice a reduction in performance

Don’t wait until these issues occur before cleaning the filter. Get into the habit of proactively cleaning it on a regular basis as part of your ongoing maintenance routine.

What You’ll Need

Cleaning the air filter is a fast and easy process that doesn’t require many supplies. Here’s what you’ll need to have on hand:

  • Lawn mower owner’s manual – Consult this for model-specific instructions
  • Clean work area – This can be your garage, driveway, etc.
  • Clean rag – An old T-shirt or towel works well
  • Small brush or air compressor – For removing debris
  • Mild solvent (optional) – Such as kerosene or carburetor cleaner
  • Replacement air filter (optional) – Only needed if the current one is very dirty or damaged

How to Clean a Foam Air Filter

Many lawn mowers have simple foam air filters that can be cleaned and reused multiple times. Here are the steps for cleaning this type of filter:

  1. Locate the air filter housing on the side of the engine.
  2. Open the housing and carefully remove the old filter. Be careful not to damage it.
  3. Inspect the filter. If it’s excessively dirty or falling apart, replace it with a new one.
  4. To clean a reusable foam filter:
    • Use a small brush or air compressor to remove dirt and debris from the filter surface.
    • Wash the filter in warm water and mild detergent. Rinse it thoroughly.
    • Allow the filter to air dry completely before reinstalling.
  5. Use a clean rag to wipe any dirt or dust out of the air filter housing.
  6. Reinstall the clean, dry foam filter into the housing.
  7. Replace the housing cover and secure it tightly.

Be careful not to over-clean the foam filter. The foam is porous by design and needs some dirt in the pores to help filter the incoming air. If the pores get too clean, unfiltered air can bypass the filter and enter the engine.

Cleaning a Paper Air Filter

Some mowers use paper air filters instead of foam. Here are the steps to clean this type of filter:

  1. Remove the filter and inspect it. Replace if torn or damaged.
  2. To clean, gently tap the filter on a hard surface to loosen and remove dirt.
  3. Spray the filter with solvent and allow it to soak for 5 minutes.
  4. Use compressed air to blow out remaining dirt. Spray lightly with solvent and repeat as needed.
  5. Allow the filter to dry completely before reinstalling.
  6. Wipe out any dirt in the air filter housing using a clean rag.
  7. Reinstall the filter and housing cover.

When cleaning a paper filter, be careful not to oversaturate it with solvent. Allowing it to air dry fully will help prevent potential engine damage from liquid bypassing the filter.

Cleaning the Pre-Filter

Some mowers have a pre-filter or foam wrap surrounding the main air filter. This catches large debris before it reaches the filter. Here’s how to clean it:

  1. Locate the pre-filter outside the main air filter.
  2. Remove and clean it using the same process as a foam air filter:
    • Brush off loose dirt.
    • Wash in mild detergent.
    • Rinse and allow to fully air dry.
  3. Reinstall the pre-filter before putting the main filter back in.

Troubleshooting Air Filter Issues

If you’re still experiencing mower performance issues after cleaning the air filter, here are some things to check:

  • Inspect the air filter and pre-filter again for holes, cracks, or gaps where unfiltered air could be leaking past. Replace damaged filters.
  • Make sure the air filter housing is properly sealed and the cover is secure after cleaning and reinstalling the filter.
  • Check that the air intake and carburetor are clear of obstructions and not clogged with dirt or debris.
  • Examine the fuel filter, fuel lines, spark plug, and carburetor for additional potential issues.
  • Review the mower owner’s manual and follow any diagnostic tests or troubleshooting procedures.
  • As a last resort, you may need to take the mower to an authorized service center for repair.

Safety Tips for Cleaning the Air Filter

While cleaning the air filter is generally safe and straightforward, keep these safety precautions in mind:

  • Always turn the mower engine off and disconnect the spark plug before servicing the filter.
  • Wear eye protection – debris can dislodge as you remove or clean the filter.
  • Use mild solvents only in well-ventilated outdoor areas.
  • Let the filter dry fully before reinstalling to prevent engine damage.
  • Secure the filter housing cover properly to prevent dislodging.
  • Wash your hands after handling the used filter.
  • Dispose of damaged or worn filters properly.

Regular Maintenance Is Key

While cleaning the air filter whenever you notice mower performance issues is important, the best practice is to add it to your regular maintenance routine. Here are some tips for keeping it cleaned on schedule:

  • Refer to your owner’s manual for the recommended service intervals (usually every 25 hours of use).
  • Mark your calendar to remind yourself when it’s time.
  • Clean the filter each spring before using your mower for the season.
  • Check and clean the filter more frequently when mowing in dusty or sandy conditions.
  • Replace your air filter at least once per year or when overly dirty.
  • Always follow your mower manufacturer’s recommendations.

Conclusion

Cleaning the air filter is one of the most important maintenance tasks for keeping your lawn mower’s engine running smoothly. While it may sound complicated, it’s really a simple and quick process. With just a few basic supplies and following the steps outlined here, you can easily clean the filter yourself and get your mower performance back up par.

Make air filter care a priority by adding it to your regular lawn mower maintenance routine. Your engine will thank you!