What Does a Lawn Mower Tune Up Checklist Include?

Look, if you’re the kind of person who likes to keep their yard looking sharp without emptying their wallet every spring, then you’ve come to the right place. Ever wonder why your mower sputters, fouls the grass, or just plain won’t start after a winter’s rest? Sound familiar? It usually comes down to skipping the proper DIY mower tune up steps. Doing a thorough spring mower service is like giving your mower a fresh start, preventing headaches and costly repairs down the line.

Before we dive deep into the nitty-gritty, let me just say this—don’t be that fella who leaves old gas in the tank all winter. What’s the worst that can happen? Old fuel gums up the carburetor, turning your mower into an expensive paperweight. Trust me, I’ve seen it a thousand times in my years running Gary’s Garage.

For all you green thumbs wanting to tackle small engine maintenance yourself, here’s a trusty tune up checklist that GardenAdvice swears by, with a bit of my own gruff wisdom added in.

Pre-Season Mower Prep

Think of this as the “wake-up call” for your mower after months of being cooped up. The first step is to give it a good look-over:

Visual Inspection: Check the mower body and wheels for damage or excessive wear. Look for loose bolts, cracks, rust spots, or any obvious problems. Clean the Deck and Body: Mower decks get caked with grass, dirt, and build-up over the season. Use a scraper or stiff brush to remove debris, then rinse with water. A clean deck improves cut quality and prevents rust. Remove Old Grass Clippings: Grass clippings hold moisture and promote rust. After cleaning, wipe everything down with an oily rag—keeps rust off and makes your mower look cared for.

Why Clean the Deck?

Think of the deck as the mower’s "workspace." If it’s clogged up, your blade can’t slice grass cleanly and evenly. A clogged deck also makes the engine work harder—wasting fuel and wearing parts faster.

Engine Maintenance: Oil, Gas, and Spark Plug

Here’s where many folks botch it by using stale fuel or forgetting to check the oil. Your mower’s engine is a small but complex critter that needs proper nourishment.

Change the Oil

Old, dirty oil is like sludge in your veins—it gums up the works and kills performance.

Refer to your owner’s manual for the right oil type. I stick with synthetic or high-grade lawn mower oil to keep things running smooth. Drain the old oil into a container and dispose of it properly. Refill with fresh oil up to the recommended level.

Pro tip: Regular oil changes keep the engine cool and lubricated, extending life and preventing costly repairs.

Drain or Replace the Gas

Listen, the absolute worst mistake you can make is letting gas sit in your mower’s tank all winter. It turns thick and varnishes lawn mower backfire fix the carburetor jets, choking your mower’s lungs. When spring comes, she struggles to breathe.

If you didn’t drain last fall, do it now:

Empty remaining fuel or add a fuel stabilizer. Run the engine until it sputters and dies to clear the carburetor. Fill with fresh, high-octane gas.

Check and Replace the Spark Plug

Think of the spark plug as the spark that lights the fire under the whole operation—a bad/plugged spark plug is like a cold fire pit; no spark, no burn.

Remove the spark plug with a wrench. Inspect it for fouling, cracks, or corrosion. Use a spark plug gapper tool to check the electrode gap to the factory spec (usually around 0.030"). Replace if worn or fouled. Don’t cheap out here—use a quality spark plug. Reinstall and tighten snugly.

Running with a worn spark plug is like trying to start a bonfire with damp wood—frustrating and inefficient.

Blade Maintenance: Sharpening and Balancing

Ever wonder why your lawn looks ragged no matter what you do? Chances are, your mower blade is dull or out of balance. Dull blades tear the grass rather than cut it cleanly—causing brown tips and an uneven cut.

Sharpen the Blade

First, disconnect the spark plug to avoid accidental starts. Remove the blade using a wrench. Use a metal file or a powered grinder to sharpen the blade’s cutting edge at the same angle it came with. Be careful not to overheat the blade—too hot and it loses temper (strength).

Balance the Blade

A blade that’s off-balance will cause vibration that shakes bearings and throws the mower off course.

Here’s where a blade balancer comes in handy:

Mount the blade on the balancer. If one side dips, file small amounts off the heavier edge until it evens out.

Balanced, sharp blades mean smoother mowing, healthier grass, and less wear on your mower’s components.

Final Check: The Small Engine Maintenance Kit

If you're aiming to keep your mower in tip-top shape year-round, consider putting together a small engine maintenance kit. Here’s a handy table listing essentials:

Item Purpose Recommendation Spark Plug Gapper Check and adjust the spark plug gap Buy quality, fits most plugs Blade Balancer Balance sharpened blades to reduce vibration Simple mechanical balancer works great Oil Drain Pan Catch used oil during change Shows respect for the environment Fuel Stabilizer Prevent stale gas deposits in carburetor Essential if you store fuel in the mower Air Filter Keep dirt and debris out of the engine Replace or clean as needed

Wrapping It Up

So, there you have it. Taking the time to do a proper tune up is the difference between a mower that struggles through the season and one that runs like a champ. Don’t be cheap or lazy about it—your mower will thank you, and your lawn will look spot-on.

Next time you get that urge to just throw the mower in the yard and call the pros, remember this checklist. You’ve got the know-how. Grab that small engine maintenance kit, get your hands dirty, and tune up that mower right. If you want to read more tricks and tips, folks over at GardenAdvice have great info that backs up what I’m saying here.

Happy mowing, neighbor.