Riding Lawn Mower: How to Prepare for the Busy Season

I’m a contractor, so I rely on my tractor to help me make a living practically every day. While I do everything from bathrooms and kitchens to basement renovations, I specialize in decks and backyard makeovers, which means earthwork and landscaping. I also do snow removal and storm recovery, and mow a few lawns now and then. None of this would be possible without my riding lawn mower. When it’s not working, I’m not working, so maintenance is key.

I trust my dealer to handle the complicated stuff—like electrical issues and new tires—but I can do a lot of the basics myself, including prepping my tractor for its busy season. Over the years, I’ve learned that some springtime prep and regular maintenance along the way are the single most important factors in keeping your machine running smoothly.

“Doing basic maintenance checks is the single most important thing you can do to get your tractor ready for the busy season,” says Mark Davey, John Deere’s go-to-market manager for compact tractors. “So make sure you understand what the different service points are and how often to perform them.” Here’s everything you need to make a strong start.

Prepping for the First Mow of the Season

The awesome thing about tractors is that they’re never fussy or hard to read: They’re usually either in full-bore “let’s go” mode, or they’re not working at all. Unlike your car, which is packed with complex electronics and an absurd amount of processing power, tractors are largely about the fundamentals—fuel, air, and spark—so there’s a lot for a DIYer to do on their own.

While some work should definitely be left to the pros, you can do a lot with an air compressor, a ratchet set, and a basic understanding of how an internal combustion engine functions. Make friends with your owner’s manual: It can tell you just about everything you need to know about keeping your tractor in great condition.

Here are some things to consider when waking your mower up for the season.

1. Mower Fluids

Frequency: Monthly
What to check: Oil, hydraulic fluid, and transmission reservoirs

Depending on the age, wear, and tear of your machine, checking fluids—mainly oil—should be a regular activity. If you have an older machine or one that’s used infrequently, you may want to check it almost every time you use it.

If your machine has hydraulics, you’ll need to make sure there’s enough compatible hydraulic fluid in the reservoir, and you should start the season by filling it or changing it completely. Hydraulic fluid can last for years, but it can go bad (one way to tell is by making sure the fluid is the right color; if it turns white, it’s gone bad).

Why It Matters

Clean fluids are your tractor engine’s lifeblood. Without them—or without enough of them—you risk the worst-case scenario: a seized engine.

The cleanliness and levels of your fluids make the machine run better and lower the overall stress on the unit in operation.

Pro Tips

• Check fluids before starting the unit.
• If oil is black, it’s dirty. Get an oil change.
• If oil’s in the bottom third of the dipstick, top it off. If it is consistently low, check for leaks.
• Hydraulic fluid and transmission fluid may or may not be the same fluid and reservoir. It’s your job to find out. Never manipulate a hydraulic line with the machine running.
• Keep fluids handy at all times. If hydraulic fluid is leaking, dirt is also getting in the system.

2. Lawn Mower Grease

Frequency: Every 10 hours of operation 
What to check: There’s nothing to check with Zerks other than keeping track of the hours since the last time you checked.

Hydraulic machines also have grease fittings, often called Zerk fittings. Using a grease gun to add compatible grease every 10 or so hours of operation is essential. Buying grease from the dealer ensures you’re using a compatible grease formula. Simply use the grease gun to inject new grease in and push old grease out. 

“With a tractor, it’s important to keep things properly greased to get that motion that you’re looking for out of them without wearing down the components,” says Davey. “If you don’t, you’ll be looking at big repair bills down the road.”

Why It Matters

The same reason fluids matter: Loaders and mowers endure incredible stresses. Grease reduces the friction and heat on the steel, allowing the unit to work as it was designed to.

Pro Tips

• A grease gun with a solid—rather than flexible—nozzle may engage the Zerk more easily.
• Engaging the Zerk requires seating the nozzle. Disengaging it requires an eccentric twist and pull.
• It takes several pumps to get grease in (stop when old grease comes out). If Zerk doesn’t accept grease, change it.
• Check the entire joint when pumping. Old grease may be coming out somewhere you can’t see it.
• Learn where Zerks are by checking the owner’s manual.
• If a Zerk doesn’t accept grease, that’s probably best left to pros.

3. Lawn Mower Spark Plug

Frequency: Annually
What to check: The condition of the current plugs and that the wire head is fully seated after it’s installed

If you’re running your machine a lot and experiencing hard starts or bumpy performance, check the plugs using a ratchet set with deep sockets. If they’re black with carbon, they need to be replaced. The type of plug you’ll need is written on the ceramic part of the plug. Depending on use, plugs should generally be swapped out annually.

Why It Matters

Fluids may be an engine’s lifeblood, but the spark is the beginning of the power cycle. A weak, inconsistent spark from a dirty plug is inefficient. The unit can idle roughly, work harder to accelerate or decelerate, and consume more fuel all at the same time.

Pro Tips

• Use the socket extension in your ratchet set for easier reach.
• Don’t over tighten new plugs. Pros use a torque wrench to seat the plug to a manufacturer specification.
• Add a dab of dielectric grease to the boot hub (the hook at the base). This helps manage any moisture in the system.
• Make sure to seat wire heads on new plugs.
• If the unit is running rough and idling hard, be sure to check the air filter along with the plugs.
• To get the exact plug for your tractor, an auto parts store or your tractor dealer is the best bet.

4. Lawn Mower Air Filter

Frequency: Every 25 hours of operation
What to check: The air filter will often be in a housing somewhere near the top or front of the engine. Remove the housing and check the filter.

Lawn care can be dusty and dirty—or it is if you’re doing it right. Air filters keep all that mung out of the engine where it can wreak havoc. Clogged air input means the engine is starved for the oxygen it needs to combust fuel properly. Accessing and replacing filters is typically an easy DIY. Clean it every 25 operating hours and replace it once per season.

What It Matters

Internal combustion engines need three things for the combustion to work: fuel, fire, and air. Limited air means limited performance.

Pro Tips

• Locating the air filter is the hardest part. If you’re having trouble, just consult your owner’s manual.
• If your property is particularly dusty or you find yourself moving lots of gravel or dry soil, keep an extra air filter on hand.
• If your unit is running rough and the filter is a mess, blow it out with compressed air to get through the day, then replace.

5. Lawn Mower Blades

Frequency: Once midseason
What to check: Hours and blade’s edge

Sharp tools work better. Period. Chisels, chef’s knives, saw blades, your brain … and lawn mower blades are no exception. A dull mower blade will leave a jagged, abusive rip on your lawn when it’s a nice clean cut you’re after. Blade sharpness can also improve the health of your lawn because yanking and pulling on the grass is more stressful to it than the sharp slice a well-tuned blade can deliver.

Assuming weekly mowing of an acre or so where the terrain is known and there is a mowing season, sharpening may only be required once midseason. Property size, rocks, and roots all play a role. Pro mow-and-blow guys use 25 hours of operation as a benchmark.

What It Matters

Dull blades tend to tear grass instead of slicing it. And grass that is healthy is the name of the game.

Pro Tips

• Find a clear, level place to get under your mower deck safely.
• Bench grinders can work for blade sharpening, but not where the blade curves. Use an angle grinder with flapper wheel.
• A Dremel tool with a sharpening stone or a bench sander can be used to retune and sharpen blades.
• Before reinstalling the blade, balance it. Set a nail or screw in the wall and place the blade on it. Whichever side is lower is heavier and needs more steel removed.
• Raise the mower deck. There are recommended cut heights by region, but I find that exceeding them makes my lawn thicker, greener, and less weedy.

6. Lawn Mower Itself

Frequency: Midseason or monthly
What to check: Underside of mower deck

Cleaning the underside of the mower deck is easy and important. Whether you side-discharge or mulch, grass clippings pile up under there. A routine check-in is key to mower performance. 

Why It Matters

The blades need time and volume of grass to turn a 1-inch grass clipping into microbits. The mower deck is designed to do this when clean, not jammed up with wet grass that has fused to the underside of the deck.

Pro Tips

• If your unit has a water hose interface, follow the blade sharpening schedule. If it doesn’t, make a visual check midseason or monthly.
• If you get a lot of rain or are dealing with overgrown acreage, check every couple of mows for buildup.

7. Lawn Mower Tires

Frequency: Monthly
What to check: Tire pressure

As a contractor, I own an air compressor, which I use to inflate tires on my tractor. The size of the tire matters. My compressor pumps about 1 pound per second. So a 20 PSI tire requires 20 seconds of air. On a larger tire, this works. But smaller tires are a different story. They fill much faster (ask me how I know), so be careful. Or use a bicycle pump. A tire that explodes in front of you is not that awesome.

Why It Matters

Tractors are heavy. They need to travel on a balanced base—that is, properly inflated tires. For four-season users, tire pressure should be optimal year-round.

Pro Tips

• Check with the dealer or auto parts store about the correct tire gauge for your unit.
• You may need a large-tire pressure gauge for bigger machines.
• Unless there’s an obvious problem, tire pressure should be checked monthly per manufacturer requirements—especially if snow removal is part of your tractor duty, as colder temperatures saps tire pressure.

8. Lawn Mower Fuel

Frequency: As your fuel runs out
What to check: Fuel source

Several operators and mechanics insist typical gas station fuel isn’t the best for tractors. Tractors have more rubber components than cars do, and ethanol tends to corrode rubber parts. A deteriorated rubber fuel line may deliver corroded rubber into the gasoline vapor produced by the carburetor and eventually clog the carb fuel lines. It may decay the rubber gasket under your fuel cap and introduce rubber into the gas tank. And by “may” I mean it happened to me.

Why It Matters

The only thing that should ever be in your fuel line is fuel.

Pro Tips

• Locate no-ethanol fuel sources in your area.
• Store an extra gas can if it is not close to you.
• Use fuel stabilizer.