Carburetor for B&S 594601 796587 591736 Fits 19HP 19.5HP 20HP 20.5HP 21HP Engine Craftsman Riding Lawn Mower Tractors Replace Intek Single Cylinder OHV Motor Nikki Carb with Fuel and Air Filter

What It Is

This is a complete replacement carburetor assembly for Briggs & Stratton Intek single-cylinder OHV engines, commonly used on Craftsman riding mowers and tractors. It includes the carburetor, fuel filter, and air filter, making it a direct swap for worn or clogged OEM units.

Fitment & Compatibility

• Engine models: Fits B&S 594601, 796587, 591736 carburetors; compatible with 19HP, 19.5HP, 20HP, 20.5HP, and 21HP Intek single-cylinder OHV engines.
• Machine brand: Designed for Craftsman riding mowers/tractors, but also fits many other brands using the same B&S engine (check your engine model number, not just mower brand).
• What to check before buying:
  • Locate your engine’s model, type, and code numbers (stamped on the blower housing or valve cover). Cross-reference with B&S 594601/796587/591736.
  • Measure the carburetor mounting bolt spacing (typically 2.5” center-to-center) and inlet size (usually 5/16” or 3/8” fuel line).
  • Verify your mower deck size (42”, 46”, 50”, etc.) is irrelevant—fitment is engine-specific only.
• OEM vs aftermarket: This is an aftermarket replacement, not genuine Briggs & Stratton. It will fit but may use slightly different gaskets or fuel line adapters.

Key Things to Know

• Quality: Most users report it works well out of the box, but a few note the gaskets are thinner than OEM—consider reusing your original gaskets if the fit seems loose.
• Installation difficulty: Moderate. You’ll need basic tools (socket set, screwdrivers) and about 30-60 minutes. The fuel line may be stiff; have a small hose clamp or zip tie ready.
• Common gotchas:
  • The included fuel filter is generic—check that it matches your fuel line diameter; if not, reuse your old one.
  • The air filter element may be slightly smaller than OEM—it works but may not seal perfectly in some housings.
  • If the engine runs rough after install, clean the carburetor bowl and jets (debris from manufacturing can cause issues).
• Adjustment: The carburetor is pre-set, but you may need to tweak the idle mixture screw (turn 1.5 turns out as a starting point).

Should You Buy It

Buy this if your Craftsman riding mower’s engine is surging, stalling, or won’t start due to a clogged carburetor, and you want a budget-friendly all-in-one kit. It’s a solid value for DIY repairs, but skip it if you need exact OEM fitment or have a non-Intek B&S engine. For the price, it’s worth trying before replacing the whole mower.