799585 Fuel Tank Cap Fit for Briggs & Stratton 550e 550ex 625e 675ex 725ex Series and 7.75-8.75 Series Fit for Craftsman 580752950 Replacement 799684 799585 591003 (2 PCS)

What It Is

This is a replacement fuel tank cap (2-pack) designed for Briggs & Stratton engines in the 550e, 550ex, 625e, 675ex, 725ex, and 7.75-8.75 series, plus the Craftsman 580752950. It seals the fuel tank to prevent leaks and debris ingress, and includes a built-in vent to maintain proper fuel flow.

Fitment & Compatibility

Before buying, confirm your engine model number (stamped on the valve cover or blower housing). This cap fits Briggs & Stratton horizontal and vertical shaft engines from the listed series, but NOT all Craftsman or generic mowers—only those using the 799585, 799684, or 591003 OEM cap. Measure your fuel tank neck outer diameter: it should be about 1.5 inches (38mm). If your cap screws on without resistance or is too loose, this won’t seal properly. Also, check that your tank neck is threaded (not a push-on or bayonet style). Not compatible with Honda, Kohler, Kawasaki, or Toro engines unless they use the same OEM cap part number.

Key Things to Know

• Quality: Aftermarket cap; some users report the vent can stick or leak if overtightened. Test-fit before full use.
• Installation: No tools needed—simply screw on clockwise until snug. Do not overtighten; hand-tight only.
• Common gotcha: The vent may be blocked out of the box. Blow gently through the cap to ensure air passes before installing. If it doesn’t vent, the engine may starve for fuel or the tank may pressurize.
• Pack of two: Useful if you have multiple mowers or want a spare, but check that both caps match—some batches have slight variations in thread depth.

Should You Buy It

Buy this if you need a quick, low-cost replacement for a Briggs & Stratton 550e–725ex or Craftsman 580752950 mower and you’ve verified the thread size and cap part number. Skip it if you want an OEM cap for guaranteed fit and vent reliability, or if your mower uses a different cap design (e.g., push-on, large-diameter, or non-vented).