Briggs & Stratton Spark Plug –  691043

Product Details & Features

Keep your Briggs & Stratton engine starting easily and running smoothly with this genuine OEM spark plug (Part 691043) — an Electromagnetic Suppression (EMS) spark plug engineered to deliver a clean, consistent spark for dependable combustion. 

Product Description:
This authentic Briggs & Stratton 691043 spark plug (also known by Champion specification QC12YC) is built to the manufacturer’s precise standards for fit, performance and durability. It features a long‑reach, projected tip, solid terminal and corrosion‑resistant shell that help provide reliable ignition under a variety of operating conditions — from cold starts to full‑power running. 

Key Features:

• OEM Quality: Genuine Briggs & Stratton spark plug designed for original equipment performance and perfect fit. 

• Strong, Consistent Spark: EMS design helps deliver stable ignition for smoother starts, steady idle and improved throttle response. 

• Durable Construction: Tough ceramic insulator and corrosion‑resistant shell stand up to heat and vibration for long life. 

• Correct Specifications: Typically fitted with a M14 x 1.25 thread, 19 mm reach and 16 mm hex — check your engine manual for exact fitment. 

• Direct Replacement: Replaces older part 499950 and matches OEM requirements for many Briggs & Stratton horizontal and vertical shaft engines. 

Why It Matters:
A quality spark plug is essential for reliable engine combustion. A worn, fouled or incorrect plug can cause hard starting, poor fuel efficiency, rough idle or misfires. Installing this genuine 691043 unit helps ensure dependable ignition, better fuel burn and smoother running — especially when servicing mowers, garden tractors, generators and other outdoor power equipment. 

Ideal for routine maintenance or tune‑ups, this spark plug helps keep your Briggs & Stratton engine performing its best season after season.