Briggs & Stratton 692046 Fuel Tank Cap

What It Is

The Briggs & Stratton 692046 Fuel Tank Cap is an OEM replacement cap designed to seal the fuel tank on many Briggs & Stratton lawn mower engines, preventing fuel leaks and debris entry. It’s a standard vented cap suitable for residential mowers, tractors, and some commercial equipment.

Fitment & Compatibility

Before buying, check your engine’s model number (stamped on the valve cover or shroud). The 692046 cap fits most Briggs & Stratton engines with a 1.5-inch (38mm) filler neck opening, including many Intek, Vanguard, and single-cylinder engines from the 1990s onward. It does not fit older engines with a 1.25-inch (32mm) neck or caps with a built-in gauge. Measure your current cap’s outer diameter and thread pitch—this cap has a coarse thread (approx. 5 TPI). If your mower uses a non-Briggs engine (e.g., Kohler, Honda), verify compatibility by measuring the neck; it’s not universal but fits many aftermarket tanks with the same thread pattern.

Key Things to Know

• Vented design: This cap has a built-in vent to prevent vacuum lock. If your engine runs rough or stalls after tightening, the vent may be clogged—clean the cap’s small hole or replace it.
• Installation is tool-free: Simply screw on by hand until snug. Do not overtighten—hand-tight is sufficient to seal; overtightening can crack the cap or neck.
• Common gotcha: Some users report the cap may not seal perfectly on older, corroded filler necks. Check for rust or damage to the tank rim before buying; a new cap won’t fix a warped neck.
• OEM vs aftermarket: This is genuine Briggs & Stratton, so fit and quality are consistent. Aftermarket caps are cheaper but may have looser venting or shorter lifespan.

Should You Buy It

If you have a Briggs & Stratton engine with a 1.5-inch filler neck and need a reliable, vented replacement that seals properly and won’t leak, this cap is a solid choice. It’s inexpensive, easy to install, and backed by thousands of positive reviews. Avoid it only if your tank neck is damaged or your engine uses a different thread size.