Spark plugs are typically located on the back or side of a lawn mower engine. Look for a short wire that's about 1/4-in. -thick leading to the top of a short, cylindrical protrusion from the engine. If you're not sure where the spark plug is, consult your owner's manual.
What is the difference between rc12yc and rc14yc spark plug? The higher number is a slightly hotter spark type plug. The RC14YC4 is now the standard plug for the 990/992 Generac engines. The 999 in the new 16-22kW Evolution (7000 series) units and older 20kW units are still using the cooler RC12YC4 plugs.
Spark plugs aren't universal; you have to make sure that you buy one that fits your mower. ... If you no longer have the manual or the number has rubbed off, you can always remove the plug first and take it to AutoZone with you.
Using WD-40 to repel water from spark plugs, distributors, alternators, and batteries is a good way to prevent corrosion and keep moisture away. You can also use it to ease the removal of spark plugs, especially if there is any rust or corrosion.
The spark plugs in both types of engine work on the same basic principle. ... Some automotive and lawn mower spark plugs may be interchangeable, but many others are not because of physical differences.