Lawn mowers are a vital tool for anyone responsible for a yard, but they have their share of problems — generally when you need them most. Luckily, many issues are easy enough to solve. You just have to know the operational basics and some of the more common DIY lawn mower repairs. Most importantly, familiarize yourself with the owner’s manual to make sure you do things safely. Here’s how to get started.
Lawn mower engines are generally gas-powered combustion engines similar to what you see in cars, but smaller. They need the same three basic elements to run: air, fuel and spark. That’s a good place to start your diagnosis. Does your mower have all three? If not, then why? Remember, always remove the spark plug from the engine to prevent accidental ignition if you are working anywhere near the blade.
Another factor to keep in mind is the environment mowers work in — dirt, dust and unkempt tall grass can all affect the basic elements of mower operation.
Not Cutting It
Is your lawn mower not starting? A common mistake owners make is storing mowers for extended periods with gas inside. Fuel quality deteriorates over time, preventing proper fuel delivery.
One of the first things to try in this situation is emptying, then refilling the fuel tank. Pull out the spark plug and examine its condition. If it’s super grimy or oxidized and you know it’s old, then change it. If it’s wet with fuel, that means the combustion chamber is flooded. Clean the plug with brake cleaner, let it dry and then try again. You might have to repeat this a few times if there’s a lot of fuel in the system.
Mow Lawn, Mow Problems
OK, so let’s say you get the mower started, but you lose power mid-mow. The culprit could be the air filter — a component that puts up with quite a lot.
If your mower stops working or loses power, remove the air filter and check its condition. You might be able to knock or blow it out with compressed air, but if it’s super dirty or ragged, you should replace it.
Speaking of dirty, check the mower’s underside and blades for a buildup of cuttings, dirt and dulled blades themselves. If you’re mowing a large or overgrown lawn, you also might be biting off more than you can chew. Double-check that your blade height setting is appropriate for the height of the grass.
It’s scary to see smoke coming from your mower, but it might not be the end of the world. Bent, loose or clogged blades could cause this, but it also might be an oil issue. Basically, any time oil comes into contact with the scalding hot metallic surface of the engine or muffler, it produces smoke. If you’ve over-filled the oil reservoir, or even if you have it at the right level but put the mower on a steep angle, oil can leak out and start smoking.
This is easy enough to clean off once you’ve let the mower cool or drain as necessary. In any case, always stop when you see smoke and check the oil level. If it’s low, you may have a leak, which will quickly result in a fried engine.
Not all lawn mower repairs are straightforward, so always consult your owner’s manual, and if these DIY tips aren’t working, call a professional. Lawn care is a lot of work, but a great source of pride if you’re doing it right.
Check out all the lawn & garden products available on NAPA Online or trust one of our 17,000 NAPA AutoCare locations for routine maintenance and repairs. For more information on DIY lawn mower repairs, chat with a knowledgeable expert at your local NAPA AUTO PARTS store.
Photos courtesy of Blair Lampe.
Blair Lampe is a New York-based professional mechanic, blogger, theater technician, and speechwriter. In her downtime she enjoys backpacking wherever her boots will carry her, rock climbing, experimental theatre, a crisp rosé , and showering love on her 2001 Sierra truck.