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Multiple models matched. Select your model to confirm fit.

Champion Spark Plug (RC12YC). The spark plug ignites the fuel and air mixture in the cylinder to power the engine. If the spark plug is burnt, fouled or damaged the engine may not start or may run rough.

NGK spark plug. The spark plug ignites the fuel and air mixture in the cylinder to power the engine. If the spark plug is burnt, fouled or damaged the engine may not start or may run rough.

Small engine Champion spark plug (RJ19LM). If the engine does not start, the spark plug may be defective. The spark plug should be replaced periodically during regular maintenance.

Briggs & Stratton Spark Plug (RJ19LM). If the engine does not start or runs poorly then the spark plug may be defective and will need replacement.

MTD Spark Plug. The spark plug ignites the fuel and air mixture in the cylinder to power the engine. If the spark plug is burnt, fouled or damaged the engine may not start or may run rough.

Small engine NGK spark plug (BPR6ES). If the engine does not start, the spark plug may be defective. The spark plug should be replaced periodically during regular maintenance.

NGK Spark Plug, (BPMR7A) SOLID

Champion Spark Plug (RJ17LM)

Briggs & Stratton Spark Plug (RC12YC), Selected Engines 3/LC Gas (.020 gap)

Champion Spark Plug (RCJ8Y). The spark plug ignites the fuel and air mixture in the cylinder to power the engine. If the spark plug is burnt, fouled or damaged the engine may not start or may run rough.

NGK Spark Plug (BPR4ES)

Champion Spark Plug (RCJ7Y). The spark plug ignites the fuel and air mixture in the engine's cylinder to power the engine. If the spark plug is has fouled (if the tip of the spark plug is burnt or damaged), the engine may not start or may run rough.

NGK Spark Plug (BPM7Y)

Plug cover

Briggs & Stratton Spark Plug (QC12YC)
A fouled or worn spark plug is the #1 reason your mower won't start or runs rough mid-season. Genuine OEM spark plugs from brands like, and fire reliably in wet grass and high-demand cutting conditions. We stock exact-fit replacements that maintain proper heat range and gap—critical for small engines.
Don't settle for plugs that may not deliver consistent ignition. Find your mower's correct spark plug and keep it running strong all summer with lawn mower spark plug parts built to factory specifications.
Need your model number? Check under the seat or on the main frame decal—then search our site to find the exact spark plug your mower needs.
Your spark plug is the heart of ignition. Get answers about replacement intervals, finding the right part, and why OEM matters for many major brands.
Most manufacturers recommend spark plug replacement every 100-200 operating hours, or at least once per season. If your mower sits unused over winter, replace the plug before spring startup—old plugs collect moisture and carbon, making cold starts nearly impossible. Check condition monthly during active mowing.
OEM spark plugs are engineered for your specific engine's compression ratio, fuel mixture, and ignition timing. They fire at the exact heat range needed—too cold and you get fouling; too hot and you risk preignition. Aftermarket plugs may appear identical but often misfire or wear faster, especially in, and small engines. Genuine parts support proper fit and performance and prevent costly engine damage.
Locate your mower's model number on the frame badge (usually near the handle or under the seat) and enter it in our parts finder. We'll display the exact OEM spark plug, gap setting, and installation torque. Never guess—using the wrong plug can can create compatibility or performance problems and harm engine performance.
A misfiring plug often points to a weak ignition coil, contaminated fuel, or a clogged air filter restricting air-fuel mixture. Always replace the air filter and fuel filter alongside a new spark plug. If misfiring persists, test the ignition coil—a faulty coil won't fire even a brand-new plug.


Ensure your Lawn Mower spark plugs are functioning with genuine OEM lawnmower spark plug replacement parts from Repair Clinic. Lawn mower spark plugs are important to replace because they ensure proper ignition of the fuel, allowing the engine to start easily and run efficiently. Use our easy model number lookup to find the exact spark plug part for your Lawn Mower, and take advantage of fast shipping and our Price Match Guarantee. Need help with installation? Visit our Lawn Mower Repair Help page or browse other Lawn Mower Spark Plug Parts.
The fastest way to the right lawn mower parts is your model number, usually printed on a label under the seat or on the frame near the blade deck. If it is not there, check the engine housing or another identification label on the mower. Copy the complete number, including letters and hyphens. Drop it into the search bar and you will see only the parts that fit your exact model across the full lawn mower catalog, rather than just spark plug options. Match the model before comparing parts, since similar mowers can use different engines and parts. This saves time and helps prevent ordering a part that looks right but does not fit.

Regular spark plug replacement keeps your Lawn Mower starting cleanly and running at full power. Repair Clinic stocks OEM spark plugs for a wide range of engines, along with installation videos and gap-setting guides. Use the model number lookup to confirm the exact spark plug specification for your engine, and keep a spare on hand for the next tune-up.

Repair Clinic has five ways for you to stop your lawn mower from leaking gas. Before we get to those, let's review how the gasoline you pour into the tank powers the mower.

Why does your lawn mower battery keep dying? Repair Clinic has done the research and this article will provide some answers, starting with what a battery's purpose is on a gas-powered lawn mower.

What's causing that black smoke to billow out of the engine? There are three likely reasons and they are all related to how a gas-powered lawn mower engine operates.