Prepping Your Lawn Tractor for Spring

by Joseph Truini

As winter fades into the distance, it's time to get your lawn tractor ready for the spring and summer mowing season. And to ensure that the mower starts easily, runs smoothly and cuts cleanly throughout the next several months, it's important to perform a preseason checkup that includes engine maintenance, parts inspection and a thorough cleaning.

Listed below are 10 maintenance tips and techniques that'll keep your mower humming along straight through until the end of summer. That might sound like a lot of work, but it's not; most of these tasks only take a few minutes to complete. Plus, regular maintenance is the very best way to extend the life of your mower and ensure that it runs reliably for many more years. Note, too, that most of the following maintenance tips can be used to prep rear-engine riding mowers, zero-turn mowers and even walk-behind lawnmowers.

Say Goodbye to Old Gas!!

Old gasoline must be drained from the tank and disposed of properly. If not, it can clog fuel lines, gum up the carburetor and prevent the engine from starting. To avoid this problem next year, allow the mower to run until it's out of gas, then store it away for the winter. That way, you'll be sure the gas tank, fuel lines and carburetor are clean of gas.

Rear-engine riding mowers are more compact than lawn tractors,
but require the same level of care and maintenance.

Replace Fuel Filter

The fuel filter is a small, innocuous-looking part that plays a key role in keeping a lawnmower running smoothly. The cylindrical filter strains the gas before it reaches the carburetor, thus preventing foreign particles from clogging the engine. A dirty fuel filter will also dramatically reduce fuel efficiency and cause the engine to run too lean, which makes it difficult to start. Check the owner's manual for the filter's model number and to find out how often it must be replaced. New fuel filters typically cost between $5 and $10, depending on the mower make and model.

Change the Oil

The lifeblood of any engine is its motor oil. Running the mower with dirty oil or low oil will shorten the life of the engine and, in extreme cases, cause the engine to seize up permanently. You should change the motor oil at the beginning of each mowing season. Be sure to use the exact type and weight of oil recommended by the mower manufacturer. It's equally important to check the oil level every time prior to starting the engine. Then add a little oil, when necessary, as indicated by the dipstick.

Install a New Air Filter

The whirring blades of a lawn tractor stir up clouds of dust, dirt and grass clippings. Without an air filter, all that debris would be sucked into the engine's combustion chamber, causing a whole host of problems: poor fuel efficiency, hard starting, rough running and shorter engine life. Inside the air filter is a paper or foam filter that protects the engine by trapping harmful airborne particles. (Dual-element filters have both paper and foam filters.) Replace your mower's air filter at the start of each mowing season. New air filters usually cost between $6 and $10.

Clean the Spark Plugs

A spark plug won't produce a powerful enough spark to fire the engine if its electrodes are worn, dirty or damaged. That's why it's important to remove, inspect and clean the spark plugs each spring. Start by disconnecting the electrical lead from the spark plug, then clean the area around the spark plug to prevent any dirt from falling into the engine. Use a spark plug socket to remove the spark plug. Inspect the spark plug to see if the porcelain is cracked or the tip of the electrode has burned away. Replace the spark plug if you see any damage. Be sure to install the exact model of spark plug recommended by the mower's manufacturer.

If the spark plug is undamaged, use a wire brush to clean off any caked-on deposits from the electrode. For stubborn, hardened deposits, carefully scrape the electrode clean with a pocketknife. Next, use a feeler gauge to check the spark plug gap. Look in the owner's manual for the proper gap distance. (Most lawn mower spark plugs require a gap of either .020 inch or .030 inch.) Hand-thread the spark plug back into the engine, then tighten it with the socket, being careful not to over-tighten it.

Check the Battery

If a mower sits idle for several months, it's not unusual for the battery to die or lose power. You can try recharging a dead battery, but if that doesn't work, you'll need to replace it with a new battery. The best way to extend the life of the mower's battery is to remove it at the end of the mowing season and store it indoors. Then, come spring, use a battery charger to charge the battery before you put it back into the mower.

Inspect the Blades

Most lawn tractors have three relatively short blades that provide a total of six sharp cutting edges.

Each spring, inspect the lawnmower blades to ensure they're sharp and not damaged. Caution: Before touching the blades, disconnect the leads from the spark plugs to prevent accidental starting. Dull blades will rip and tear the grass, which causes the ragged tips of the blades of grass to turn brown. Have the blades sharpened by a professional at the first sign of dulling. Replace any blades that are bent, cracked or badly chipped.

Check the Tires

Use a tire gauge to check the air pressure in each tire. If necessary, fill each tire to the recommended air pressure (usually between eight and 12 PSI). Replace any tires that won't hold air, or that have bald treads or badly cracked sidewalls.

Lube Up the Joints

Lubrication is an important but often overlooked part of lawn mower maintenance. Poorly lubricated joints and parts will wear out prematurely and stop functioning. Consult the owner's manual for the location of all the grease fittings; some can be difficult to see. Then, use a grease gun to squeeze grease into each fitting. Stop squeezing when grease starts oozing out of the joint.

Clean the Mowing Deck

It's good practice to frequently hose off and wipe down the lawn tractor, but it's more important to clean matted grass from the underside of the mowing deck. This is especially a problem when mowing wet grass, which tends to stick to the metal deck. Caution: Disconnect the leads from the spark plugs to prevent accidental starting.

Grass-collection systems are notorious for clogging up with
grass clippings and shredded leaves. Clean the entire system at the
start of the mowing season and each time you mow wet grass.

It's relatively easy to clean the deck immediately after mowing, but if the grass has dried over the winter, it takes quite a bit of elbow grease to remove the hardened mass of grass. Start by raising the mowing deck as high as possible, then reach underneath with a plastic putty knife or thin wooden stick and scrape away the matted grass. Don't use a sharp metal tool—you could scratch the underside of the mowing deck and expose the metal to rusting.

If your mower has a grass-clipping collection system, be sure to also thoroughly clean the fabric bags or plastic bins, and the inside of the large diameter feed tube that delivers the grass clippings from the mowing deck.

By performing these 10 maintenance tips, your lawn tractor will provide reliable, trouble-free service throughout the spring and summer. Happy mowing!

About the author: Joseph Truini is a home improvement expert that writes for The Home Depot and is also the author of several DIY books. Joe provides how-to advice on a variety of topics, including how to maintain your riding lawn mower properly.