Briggs & Stratton

What It Is

This is a genuine Briggs & Stratton replacement air filter (part number 491588S) for small engines in walk-behind mowers, riding mowers, and garden tractors. It traps dirt and debris before they enter the carburetor and cylinder, protecting the engine from premature wear.

Fitment & Compatibility

Check your engine’s model number (stamped on the valve cover or blower housing) against the 491588S parts list. This filter fits many Briggs & Stratton single-cylinder engines with a 8.75–10.5 ft-lbs torque range, including the 500E, 550E, 625E, and 725EXi series. It does not fit engines that use a foam-only or larger rectangular filter. Measure the filter housing opening (approx. 2.5” x 1.5”) to confirm shape. OEM part, not aftermarket—direct replacement for the factory filter.

Key Things to Know

• Quality: Genuine Briggs paper element with foam pre-filter; better filtration and fit than generic clones.
• Installation: Tool-free—just unclip the air filter cover, swap the old filter, and re-secure. Takes 30 seconds.
• Maintenance: Replace every 25 hours of operation or once per season, more often in dusty conditions. A dirty filter reduces power and increases fuel consumption.
• Gotcha: Some aftermarket covers require a slightly different filter shape—verify your cover clip style before buying.

Should You Buy It

If you own a compatible Briggs engine and need a reliable, budget-friendly air filter that matches OEM specs, this is a no-brainer. It’s perfect for routine maintenance, especially if you prefer genuine parts over generic options. Skip it if your engine uses a different filter shape or you’re looking for a high-flow performance upgrade.