Briggs and Stratton 1687017SM 20 inches Mower Blade

What It Is

This is a genuine OEM 20-inch mower blade from Briggs & Stratton (part number 1687017SM), designed for residential lawn tractors and zero-turn mowers that require a medium-lift blade for general cutting and bagging.

Fitment & Compatibility

• Deck size: Confirms to a 20-inch blade length (measure from cutting edge to cutting edge, not the overall length including mounting holes).
• OEM vs aftermarket: Genuine Briggs part; aftermarket alternatives may exist but check for exact hole pattern and center hole diameter.
• Mounting: Uses a standard 1-inch center hole with a 5-point star pattern (common on Briggs engines). Verify your spindle mount matches.
• Check before buying: Measure your current blade length, center hole diameter, and hole pattern. Confirm your mower deck brand and model (e.g., Craftsman, Troy-Bilt, Murray) uses a Briggs engine and spindle.

Key Things to Know

• Quality: Made from hardened steel with a balanced design; holds an edge well but may need sharpening after 10-15 hours of heavy use.
• Installation difficulty: Easy (15-20 minutes) with basic tools—socket wrench, torque wrench (45-55 ft-lbs), and a blade removal tool. Always disconnect the spark plug first.
• Common gotcha: This is a medium-lift blade, not high-lift or mulching. It works best for bagging and standard cutting; poor for heavy mulching or leaf shredding.
• Durability: Tends to bend if hitting rocks or stumps; inspect after each season for cracks or warping.

Should You Buy It

Yes, if you need a direct OEM replacement for a Briggs-equipped mower with a 20-inch deck and you prioritize bagging performance over mulching. It’s reliable but overkill if you just want a cheap aftermarket blade for occasional use. Skip it if you need a high-lift blade for wet grass or a mulching blade for fine clippings.