Spring Lawn Mower Tune Up Time

Baseball season is back, and even though there may still be snow on the ground up north, it is time to start thinking about lawn car again. No matter how big your yard is, or what you use to mow it, just like your car, your lawn mower will last longer and work better with a little periodic maintenance. A poor running mower that gets bogged down easily in long grass just makes a weekend chore that much more work, but a little work in the shed now can mean less work in the yard later.

If you winterize your lawn equipment properly – storing it indoors with no gas in the tank or float bowl – that first mow of spring is much easier. Drain the tank and run the carburetor out of gas before storage for best results. At the very least add a shot of fuel stabilizer to the tank, and top off with fresh gas when the time come to use it again.

All of our mower and small engine manuals are listed under the “Outdoor Power” tab above. But, here’s a few more free tips to trouble free mowing:

1) Clean it up

The air cooled gasoline motor that powers your mower will run cooler, making more power and lasting longer, if you keep the cooling fins clean. Scrub dirt and grass out of the fins with a bristle brush and rinse clean. Mowers are made to be weather resistant, but avoid getting water in the fuel vent, and air cleaner.

Even if you use an electric mower, a periodic cleaning is a good idea. Jack up and support your riding mower, or flip your push mower on its side (watch for leaking fuel), and clean the dead dried grass from the bottom of the deck. If your mower is electric, the air vents to cool the motor are probably under there, so it is especially important. Once you remove the large chunks by hand, you can scrub it clean with a brush.

All that dead dried grass stuck to the deck can contributed to corrosion and rust. Too much old grass stuck to the underside can also make it harder to mow, not letting the blade throw the newly cut grass out of the way, and gumming things up. Once clean, spraying the underside with WD-40 or other aerosol lubricant will keep grass from sticking and prevent rust.

2) Inspection

When cleaning, give your mower an inspection and look for wear, breakage, and loose nuts and bolts. Start with the handle (on a push mower) – make sure all the bolts and knobs holding it on are tight. Lubricate the control cables and linkages and check that they move freely. Check any wiring for pinched or cracked insulation, and look for loose connections. Check the motor and the rest of the mower for screws and bolts that may be coming loose.

On riding mowers and self propelled push mowers, check that drive belts or chains aren’t getting loose or worn out. If they are not adjustable they will need to be replaced when they get slack. If there are motorcycle-like drive chains (reel mowers and some riding mowers) make sure they aren’t rusty and there are no frozen links, then clean and lubricate.

On push mowers, check that each wheel rolls freely, and isn’t cracked. On mowers with pneumatic tires, check the air pressure, but remember most should only be at 10-15 psi. Use a grease gun to lubricate the wheels bearings or any other place there is a grease fitting.

3) Stay sharp

The most important feature of the mower is a sharp blade. Having a good edge on the blade or blades not only makes mowing easier, it leaves the grass healthier and greener. A sharp blade makes a clean cut which lets the grass recover quicker, growing stronger and thicker. Grass cut with a dull blade leaves damaged ends which turn brown, ruining the look of the lawn.

The easiest way to sharpen the blade is a dedicated kit with a beveled grindstone which attaches to your drill. For less than $20 at any hardware store or online, you can get a kit that will sharpen the blade in minutes. It easily pays for itself in the time you save by mowing with a sharp blade

Taking the blade (or blades) off may require some effort. You may find it helpful to jam a piece of wood against the blade so it can’t rotate as you loosen the nut. When reinstalling be sure to tighten the retaining nut properly. The recommended torque is different depending on the diameter of the shaft, but typically you needn’t worry about overtightening.

NOTE: On mowers with two blades, one may rotate in the opposite direction, and the nut may be reverse threaded.

Old fashioned reel mowers are more complicated when it comes to sharpening and adjusting the blade. Adjustment the straight blade at the back, then crank the reel in reverse with an abrasive lapping compound. They should work together just like scissors through paper.

4) Motor maintenance

Gas powered mowers will often last a decade with little to no care from the typical homeowner. But if you rely on your mower for a living, or want to make it last even longer, there is a bit of maintenance you should do every year. Just like an old motorcycle, changing the oil in your mower and replacing the air filter and spark plug can make a big difference in performance.

If your mower has a car-like paper air cleaner, take it out and tap it to remove the loose dust. If you can’t see light through it, it is time to replace it. Foam air filter elements can be cleaned with soap and water, and re-oiled just the the one in your bike.

Not all mowers have oil drain plugs that go through the deck, which is the easiest way to drain them. Often, you just need to remove the plug, and tilt the mower so that the oil runs off the deck. Refill with about a 1/2 quart of the recommended motor oil (as marked on the fill cap). Most small engines in mowers take very little oil, so clean oil is much more important than in a car with 6 quarts.

Modern spark plugs and ignitions can go years without fouling, but if the mower becomes hard to start, a new plug is probably in order. Once a year take the plug out and check the color and condition of the electrode. If it is black or oily, your motor may be burning oil and worn out. Check the condition of the spark plug wire too.

For more specific small engine service advice, see the Clymer line of small engine manuals. These books cover mowers, generators, chainsaws, rototillers, lawn tractors, and more. Find yours here: Outdoor Power Manuals.

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