Carburetor for Briggs & Stratton Craftsman 17.5 500cc Engine

What It Is

This is a replacement carburetor for Briggs & Stratton 500cc (17.5 horsepower) engines commonly used on Craftsman lawn tractors and riding mowers. It meters fuel and air into the engine’s intake, and you’d replace it when the engine runs rough, stalls, won’t start, or floods despite cleaning the old one.

Fitment & Compatibility

Critical checks before buying:

• Engine model: Must be a Briggs & Stratton 500cc (17.5 HP) single-cylinder engine. Look for a model number stamped on the engine shroud (e.g., 31C707, 31P977, 31R907). This carburetor is not universal—it fits specific 500cc series only.
• Deck size / mower brand: Fits most Craftsman tractors with 42" to 54" decks that use this engine. Not compatible with smaller push mower engines (e.g., 190cc, 450cc) or other brands like Husqvarna/John Deere without cross-checking engine model.
• OEM vs aftermarket: This is an aftermarket part. OEM Briggs part numbers include 594905, 594904, or 590454—compare those numbers to your engine’s original. Aftermarket may fit but can vary slightly in gasket thickness or jetting.
• Measurements: Verify the carburetor mounting flange spacing (approx. 2.5” center-to-center) and fuel inlet diameter (usually 1/4”). Measure your old carb’s bowl and float dimensions before ordering.

To confirm fit: Remove your old carb, find the Briggs engine model number (on a decal near the spark plug or under the fuel tank), and search “carburetor for Briggs model [your number].”

Key Things to Know

• Quality: Budget aftermarket carb. Likely uses plastic or aluminum components that may not match OEM durability. Expect to adjust the idle mixture screw after install.
• Installation difficulty: Moderate. You’ll need to remove the air filter, fuel line, and linkage springs. A basic socket set and a small screwdriver are enough. Watch for tiny springs—they’re easy to lose.
• Common gotchas:
  • The fuel line may be 1/4” vs 5/16”—check your mower’s hose size. A mismatch causes leaks.
  • The included gaskets may not align perfectly with your intake manifold. Reuse your old OEM gasket if needed.
  • Aftermarket carbs often need the float level adjusted manually (bend the tang slightly). Don’t skip this.
• Reviews: Only 1 review (5.0/5). Minimal feedback means risk—buy from a seller with free returns.

Should You Buy It

This is a budget-friendly option for DIYers who can handle minor adjustments and have already confirmed engine model fit. It’s right for you if your 500cc Briggs & Stratton is running poorly, you’ve cleaned the old carb with no improvement, and you’re comfortable with basic tools. Skip it if you want guaranteed OEM quality or lack the time to dial in the mixture—spend ~$20 more for a genuine Briggs carb.