Briggs & Stratton air filters come in several types, and the one you need depends on your engine model and the equipment it powers
Briggs & Stratton makes engines for lawn mowers, generators, pressure washers, and other outdoor power equipment. Each engine model uses a specific air filter size and connection type. The filter sits between the carburetor and the outside air, catching dust and debris before they reach the engine. Using the wrong filter — or running without one — lets particles into the fuel system and damages the engine over time.
Your engine's model and type number appear on a metal plate bolted to the engine block. That number is what you need to find the correct filter. Briggs & Stratton publishes filter cross-reference charts on their website and through authorized dealers, and most hardware stores and online retailers can look up the right part by engine model.
Key Takeaways
- The engine model and type number on your Briggs & Stratton engine determine which air filter you need; this information is stamped on a metal plate attached to the engine.
- Briggs & Stratton air filters come in paper cartridge, foam, and dual-element designs, each suited to different equipment and operating conditions.
- You can find the correct filter through Briggs & Stratton's official parts lookup tool, authorized dealers, or by providing your engine model number to a hardware or online retailer.
- Most air filters should be inspected every 25 to 50 hours of operation and replaced when visibly clogged or discolored, though heavy-use equipment may need more frequent changes.
How to locate your engine model and type number
The identification plate is usually mounted on the side or top of the engine block with bolts or rivets. It is a small metal tag with white or silver text printed on a dark background. The plate lists the model number, type number, and code number — you need the model and type to find your filter.
Write down the complete model and type numbers exactly as they appear. Do not abbreviate or guess at digits. If the plate is worn or hard to read, take a clear photo with your phone and zoom in on the image. Once you have the numbers, you can search Briggs & Stratton's parts website or call an authorized dealer with the information.
The three main air filter types Briggs & Stratton uses
Paper cartridge filters are the most common. They consist of a pleated paper element inside a plastic or cardboard housing. The paper traps dust as air passes through. These filters work well for standard mowing and light-duty use. They are inexpensive and widely available at hardware stores and online.
Foam filters are made from open-cell foam material and are often used on equipment that runs in dusty conditions or wet environments. Foam filters can be cleaned and reused several times before replacement, which makes them cost-effective for frequent users. Some models use foam as a pre-filter wrapped around a paper cartridge for extra protection.
Dual-element filters combine a foam outer layer with a paper cartridge inside. The foam catches large particles and can be cleaned, while the paper cartridge handles fine dust. These are common on larger engines and commercial-grade equipment. They offer longer service life than paper alone but cost more upfront.
Where to buy the correct filter
Briggs & Stratton filters are sold through multiple channels. Authorized dealers — often small engine repair shops or lawn equipment retailers — stock filters for popular models and can order others. Home improvement chains like Home Depot and Lowe's carry a range of Briggs & Stratton filters in their lawn and garden sections. Online retailers including Amazon, eBay, and specialty sites like Jack's Small Engines stock both common and hard-to-find models.
Before you buy, confirm the part number matches your engine. The part number usually begins with "491" or "492" for Briggs & Stratton filters. You can verify it against your engine model using Briggs & Stratton's official parts lookup at their website, or by calling an authorized dealer with your model and type numbers. Buying the wrong size wastes money and leaves your engine unprotected.
How often to inspect and replace your air filter
Briggs & Stratton recommends checking your air filter every 25 to 50 hours of operation, depending on how dusty your environment is. If you mow a small lawn once a week, that is roughly every two to four weeks during the season. If you use your equipment in sandy, dry, or heavily trafficked areas, check it more often.
Replace the filter when it looks clogged, discolored, or torn. A clean filter is white or light tan; a dirty one is dark gray or black. If the filter is foam, you can rinse it gently with warm water and mild soap, let it dry completely, and reuse it — but replace it if it tears or does not clean up. Paper filters cannot be cleaned and must be replaced once they are clogged.
Steps to replace your air filter
First, stop the engine and let it cool for at least five minutes. Locate the air filter housing — it is usually a plastic or metal box bolted to the top or side of the engine near the carburetor. Remove the bolts or clips holding the housing cover in place. Some covers snap off without tools.
Lift out the old filter and note how it sits in the housing. Wipe the inside of the housing with a dry cloth to remove loose dust. Insert the new filter, making sure it sits flat and fully inside the housing. The filter should fit snugly without gaps around the edges. Replace the cover and tighten the bolts or clips firmly but not so hard that you crack the plastic housing.
Do not run the engine without the filter or with a loose cover. Debris will enter the carburetor and fuel system, causing the engine to run poorly or stall. Once the cover is find, start the engine and listen for any unusual sounds. The engine should run smoothly.
Common mistakes to avoid
Using a filter from a different engine brand or model may fit loosely or not at all, leaving gaps where unfiltered air enters the engine. Always verify the part number before you buy. Reusing a paper filter that is clogged reduces airflow and forces the engine to run rich, wasting fuel and producing excess smoke. Replace paper filters; do not try to clean them.
Installing the filter upside down or at an angle prevents it from sealing properly. Take a moment to look at how the old filter sat before you remove it, or take a photo. Some filters have a flat side and a domed side — the orientation matters. If you are unsure, check the instruction sheet that comes with the new filter or watch a video for your specific engine model.
Frequently Asked Questions
Can I use a generic air filter instead of a Briggs & Stratton brand filter?
Yes, if the generic filter has the same part number or is listed as a direct replacement for your engine model. Many aftermarket filters are made to the same specifications and work well. Always confirm the part number and dimensions match before you buy. Avoid very cheap filters with no brand name or reviews, as they may not seal properly.
What happens if I run my engine without an air filter?
Dust, pollen, and debris will enter the carburetor and fuel system. The engine will run rough, lose power, and may stall. Over time, particles damage the carburetor jets and fuel lines. Repairs cost far more than a filter. Never operate the engine without a filter or with the housing cover off.
Can I clean and reuse a paper air filter?
No. Paper filters are designed to be replaced, not cleaned. Attempting to wash or blow out a paper filter can tear it or push trapped particles deeper into the fibers, reducing its effectiveness. Foam filters can be cleaned and reused several times, but paper filters should be discarded once clogged.
How do I know if my air filter is clogged?
A clogged filter looks dark gray or black instead of white or light tan. The engine may run rough, use more fuel, or produce excess smoke. If you have not changed the filter in over a season, or if you use the equipment frequently in dusty conditions, replace it. When in doubt, hold the filter up to a light — you should see light passing through easily.
Where can I find my engine model number if the plate is missing or unreadable?
Contact an authorized Briggs & Stratton dealer with a photo of your engine and the equipment it powers. They can often identify the model by the engine's appearance and the type of equipment. You can also call Briggs & Stratton customer service with a description of your mower or equipment and when you bought it.