One Mow Time: Keep It Tuned Up

House Doctor | Gary Dymski

March 20, 2003

With a little care, that gas-powered lawnmower tucked in the corner of your garage can be one of the most dependable machines you own.

"I have one customer whose mower has to be 30 years old," says Michael Squires, owner of Tuttle's Mower Service in Eastport. "It is regularly maintained, and that's why it has lasted so long.

"I have other customers who have mowers that are 1 or 2 years old, and when they bring them in all I can do is toss them in the trash heap."

The difference between long-lasting mowers and trash, experts say, is maintenance. According to a survey by Briggs & Stratton, the world's largest manufacturer of small, air-cooled engines for outdoor power equipment, 66 million households in the United States own power mowers. Of those households, more than 40 million do not perform any maintenance.

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That's a lot of sputtering, coughing power mowers.

"Most of the time, I see a mower only when someone has a problem," says Jeff Woolard, a small-engine mechanic for 23 years and a salesman at Centereach TrueValue Hardware. "That's neglect."

Mowers and other gas-powered power equipment - yard blowers, trimmers, snowblowers and chain saws - should be tuned up annually. At the very least, homeowners can refer to owner's manuals to help them perform some of their own maintenance, like changing oil, spark plugs and air filters.

To make sure your mower is running right when the grass turns green and is begging for a trimming, get it tuned up early. "Now is a perfect time to bring it in and have it ready," Squires says. "In the next few weeks, I'll be getting 20 mowers a day, and it will take longer to get it back."

A full mower tune-up usually includes changing spark plug, oil and air filter, cleaning the carburetor, sharpening the blade, lubrication and performing a general inspection. Replacing parts, such as belts and cables, can be extra.

The Briggs & Stratton survey says that a power-mower tune-up, which runs between $50 and $60, can reduce fuel consumption by up to 30 percent, increase horsepower by 7.5 percent and extend mower life.

Warning signs that mowers need maintenance can include difficulty in starting, smoking engines and reduced horsepower. A mower that is hard to start is among the first signs it is overdue for maintenance. "The newer engines are designed to start with one or two pulls of the starting cord," Woolard says. "You prime the engine with a push of a button, pull and go. If it takes more than two pulls to start, it usually needs some work."

Homeowners can extend the time between tune-ups by following the guidelines in the mower's owner's manual and using fresh gasoline. Oil, for example, should be changed about every 20 hours of run time. A blade should be sharpened at least twice during a mowing season, and a new spark plug should be installed at the start of each season.

One common mistake among homeowners, says Woolard, is using old gasoline or not draining gasoline from engines during winter months.

"Gasoline has a very short shelf life," Woolard says. "If it is left in the tank during the winter, it gets gummy and the carburetor gets sticky. I work on a lot of sticky carburetors in the spring."

Woolard advises that a fuel stabilizer be added to gasoline at the beginning of a mowing season. A 10-ounce container of stabilizer, which runs about $4, can treat about 25 gallons of gasoline. "If you add it to your gas can, then each time you fill the tank you'll have stable fuel in the mower," Woolard says.

Squires, however, does not advocate stabilizers. He says to use fresh gas regularly; use gallon-size gas cans and fill them often (gas has a shelf-life of about 60 days). He also says to drain gas from gas-powered equipment that might not be used weekly or biweekly, machines such as line trimmers, blowers and edgers.

"All the additives in unleaded gasoline, I believe, have helped cut the shelf life," he says. "I've had gas in the shop that is about a month old, and I've used it to run tuned-up mowers. A few weeks later, I've had to reclean that machine's carburetor."

Woolard's advice to use stabilizer might be the more practical solution. Even though a stabilizer is an added expense, one or two containers each season likely will cover all of your power equipment.

At the end of the season, it's crucial to drain that gas from the mower and other equipment so it does not "gum up" the carburetor.

If a homeowner does any work on the piece of power equipment, experts advise to disconnect the spark plug. If the spark plug is left connected, there's a chance the machine could jump start when a homeowner is removing the blade or draining oil.

Squires also says mower owners should jot down the model number and serial numbers of their machines. It's handy information, especially when replacement parts are needed.

"This happens all the time," he says. "Someone will come into the shop and ask for a spark plug, and I'll ask them what kind of mower they have.

"They say, 'I have a red one. Do you have a spark plug for a red mower?'"