Vented Fuel Gas Tank Cap 2-1/4" Compatible with Ariens 01538400 for Bobcat 48587 for Briggs & Stratton 397975 493988 493988S 795027 Replacement Fuel Cap

What It Is

This is a vented replacement gas cap designed to fit a wide range of lawn mowers, tractors, and outdoor power equipment. It replaces OEM part numbers Ariens 01538400, Bobcat 48587, and Briggs & Stratton 397975, 493988, 493988S, and 795027. The cap allows air into the fuel tank to prevent vacuum lock, ensuring consistent fuel flow to the engine.

Fitment & Compatibility

Before buying, measure your existing cap’s thread diameter: this cap fits a 2-1/4” (approx. 57mm) opening. It is compatible with many Ariens, Bobcat, and Briggs & Stratton models, including zero-turn mowers, walk-behinds, and lawn tractors. However, always cross-reference your equipment’s model/serial number with the OEM part numbers listed. Note that this is an aftermarket cap, not OEM, so fitment may vary on older or less common machines. If your cap has a different thread pitch or a non-standard diameter, this will not work.

Key Things to Know

• Installation is tool-free: Simply twist off the old cap and screw on the new one by hand. No special tools or sealants needed.
• Vented design is critical: If your engine runs rough or stalls after a few minutes, a clogged or non-vented cap is a common cause. This cap prevents that issue.
• Check for proper seal: Ensure the rubber gasket sits flat and the cap tightens snugly. A loose cap can cause fuel leaks or poor performance.
• Quality note: At this price point, the plastic and vent mechanism are basic but functional. It may not last as long as an OEM cap in harsh conditions (extreme heat or sun exposure).

Should You Buy It

If you need a quick, affordable fix for a lost, broken, or non-venting fuel cap that matches the listed OEM numbers and has a 2-1/4” opening, this is a solid choice. For heavy commercial use or if you prefer OEM build quality, consider spending more on an original part.