(Pack of 8) Champion Spark Plugs, RC12YC for Copper Plus Small Engines # 71G

What It Is

This is a pack of eight Champion RC12YC Copper Plus spark plugs (model #71G), designed for small engines in lawn mowers, tractors, generators, and other outdoor power equipment. The copper core provides reliable ignition for standard-duty use.

Fitment & Compatibility

Before buying, check your equipment’s owner’s manual or existing plug for the correct gap and thread size. RC12YC has a 14mm thread, 19mm (3/4") reach, and a 5/8" hex. It fits many Briggs & Stratton, Tecumseh, Kohler, and Honda engines, but not all—verify OEM part numbers like 5095, 71G, or 802592. For mowers, this plug is common for engines 3.5–20 HP, regardless of deck size. Measure the gap (typically 0.030” for most small engines) and adjust before installing. Aftermarket plugs are fine, but match the heat range (12 is medium-hot) to your engine’s spec.

Key Things to Know

• Quality: Copper Plus plugs are entry-level but dependable for seasonal mowing; they wear faster than iridium or platinum (replace annually).
• Installation: Easy—remove spark plug wire, unscrew old plug, gap new one, hand-tighten, then torque to 18–20 ft-lb. No special tools needed.
• Gotcha: The pack of 8 is for multi-engine households or bulk replacement; one mower needs only one plug. Check if you need the resistor version (RC12YC is resistor-type; non-resistor R12YC may be required for some older engines).
• Common mistake: Over-tightening can crack the porcelain; use a torque wrench if possible.

Should You Buy It

If you have multiple small engines (mower, trimmer, generator) that call for RC12YC, this pack offers good value at ~$3 per plug. It’s ideal for budget-minded DIYers who replace plugs annually. For a single mower, a single plug is cheaper unless you plan to stock up for future needs.