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Butom
RC12YC Spark Plug for Small Engines

Push Mowers · Spark plugs

Butom RC12YC Spark Plug for Small Engines

4.5 out of 5 · 1,337 reviews

A resistor plug that crosses to RC12YC and the common mower plug numbers.

$9.49at last check, Sep 27, 2026

Fits

  • Walk-behind mowers
  • Lawn tractors
  • Kohler engines
  • JD mowers

Replaces

  • Champion RC12YC
  • 491055S
  • 692051
  • 5066
  • JD M78543
  • Kohler 25 132 12-S

About this part

A tired plug is the cheapest reason an engine won't start, and it is the first thing we check. This plug crosses to the RC12YC used on a very large share of mower and tractor engines.

It replaces the common numbers found in owner's manuals, including 491055S, 692051, 5066, M78543 and Kohler's 25 132 12-S. Gap it to your engine's spec before you thread it in.

  • Crosses to Champion RC12YC
  • Replaces 491055S, 692051 and 5066
  • Also listed for JD M78543 and Kohler 25 132 12-S
  • An easy first check for hard starting
In the box
  • Spark plugs (multi-pack)
Specs
TypeResistor plug
Crosses toRC12YC
Before you order

Compare the stamp on your old part with the “Replaces” list, and your engine code with “Fits”. If it still isn't clear, send a photo to the counter and we'll check it for you.

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