Is your lawn mower OK? (How long has gas been in it?) Here's what suburban shops say to do.

As spring green replaces winter brown, consumers can choose from a bevy of products promising a richer, thicker lawn. But is your mower ready for another season of cutting it?

Chances are your mower has been an afterthought in the garage or shed all winter. But continuing to ignore it until you need it to fire up would be a mistake.

Equipment dealers that service and repair mowers already are busy. And by early to mid-May the wait time for a tuneup or repair will get to the point of needing grazing cows or a machete to keep your lawn under control.

So, now's the time to roll up your sleeves, dust off your mower and get to work.

"If they start, then you probably want to do an oil change, put a new air filter in and check the blade," said Carol Verley, owner of Grower Equipment & Supply Co., a staple along Route 120 in Hainesville for 40 years.

If it doesn't start or if it does but chugs, shakes, revs or otherwise doesn't seem right, there is an issue.

Inspecting and replacing the spark plug if the engine isn't running well is recommended.

Checking your owner's manual for troubleshooting, tips, guidelines and specifications should top the to-do list, say those involved in the business. Some manufacturers, for example, recommend changing the oil to start the season, while others say topping it off is OK. Can't find it? Look online.

Certainly, not everyone will need to take their mower to a pro for service, particularly if you prepared last fall by running the gas out after the last cut. If not, there are DIY steps that may be able to get you mowing.

While an old spark plug could be the culprit, old gas is one main reason mowers or small engines won't start or run well, mechanics say. Gasoline containing ethanol, like you get at the pump, is good for about 30 days or so.

Longer than that and the fuel begins to break down and absorbs water. As ingredients in old gas evaporates, a varnish-like, clog-inducing residue is produced.

"That leaves deposits in the carburetor. Some we can fix, some we can't," said Gerry Buchberger, a technician at Ray's Bike & Mower in Mundelein.

"The big thing is to purge the fuel."

Gas from the pump isn't rated for small engines, and every spring clogged carburetors are a "pretty common thing," said Richie Idstein, head of the lawn and garden department at Libertyville Ace Hardware.

"Nowadays, it's an education in fuel," he said. "That's the biggest thing that's changed."

After removing the old gas and draining the carburetor, put in fresh gas, a fuel cleaner/stabilizer and run the gas out of the tank, experts say.

After that, fill with new fuel. Go with mid- or premium-grade if using gas from the pump, suggested Ted Leatherman, lead technician at the Round Lake Ace Hardware, which services mowers from eight other Ace stores including Libertyville.

"It's not cheaper in the long run" to use the least expensive grade, he said.

Ethanol-free fuel, which can be left in the tank without issue, also is available at service shops and other stores.

"The same thing with a snowblower," said Jon Guinn, shop manager and 30-year veteran at Grower. He said there are a lot more fuel-related problems with snowblowers because of how long they can sit unused.

"The non-ethanol fuel, we don't have the same issues," he said.

As to other basics, sharp blades provide a clean cut rather than ripping the grass. It can be done at home with a grinder, but there is a bit more to it.

"The big deal is you have to balance it," Buchberger and other techs agree. "... It will start to shake and wear out the bearings in the engine."

Verley said don't run the mower if it is shaking because the blade can loosen and come off.

Battery-powered mowers don't have spark plugs but are getting close to the size and torque of gas-powered models, Idstein said.

"People gravitate toward volts, but it's the working hour amps you're looking for," he advised.

Another important consideration is to make sure the underside of the mower deck is clean to ensure efficiency. Use a garden hose followed by a brush to remove debris.

"Enough compaction (of grass or debris) will stop a blade dead," Idstein said.