42-Inch Carburetor Tune Up Kit Replacement Compatible with Troy-Bilt Pony & Bronco 13WN77BS011 13AN77KG011, 13WN77KS011 13AN77KS011 13AN77BS011 13AN77TG766 Fits Briggs & Stratton 15.5/17.5HP 500cc

What It Is

This is a carburetor tune-up kit designed for Troy-Bilt Pony and Bronco lawn tractors. It replaces the entire carburetor assembly on models with 42-inch decks and compatible 15.5 or 17.5 HP Briggs & Stratton 500cc engines.

Fitment & Compatibility

Before buying, confirm your mower’s model number exactly matches one of these: 13WN77BS011, 13AN77KG011, 13WN77KS011, 13AN77KS011, 13AN77BS011, or 13AN77TG766. Also verify your engine is a Briggs & Stratton 15.5 or 17.5 HP 500cc (typically single-cylinder). This kit is aftermarket, not OEM Briggs & Stratton—check that your carburetor mounting flange pattern matches the included gaskets. Measure your existing carburetor’s bolt spacing (usually 3.5 inches center-to-center) to be safe. It will not fit other deck sizes or engine brands like Kohler or Kawasaki.

Key Things to Know

• Quality vs OEM: At $35.99, this is a budget aftermarket kit. Expect plastic components and gaskets that may not seal as tightly as OEM—inspect for warping before installation.
• Installation difficulty: Moderate. You’ll need a socket set, screwdrivers, and possibly a carburetor wrench. Plan 45–90 minutes for removal, swapping, and reinstallation.
• Common gotcha: The throttle and choke linkage can be tricky to reconnect. Take photos before disassembly, or note the linkage spring positions. Also, check fuel lines for cracks—old lines can cause air leaks after the swap.
• Tuning required: After installation, you may need to adjust the idle and mixture screws (if adjustable). Most 500cc Briggs engines have fixed jets, so only idle speed adjustment is possible.

Should You Buy It

Buy this kit if you need a quick, low-cost replacement for a worn-out or gummed-up carburetor on a Troy-Bilt Pony or Bronco with a 500cc Briggs engine, and you’re comfortable with basic small-engine repair. Skip it if you prefer OEM reliability or have a different engine brand—spend more on a genuine Briggs & Stratton carburetor for guaranteed fit and longer life.