Causes of Lawn Mower Not Starting Forney

As winter moves toward spring, homeowners and lawn care professionals can look forward to the start of mowing season. When the grass starts growing again in the spring, you'll want to have your mower in peak operating condition for the rest of the mowing season. But sometimes, when you get your mower out in the spring, it does not run properly or won't start at all.

Several of the problems that can keep a lawn mower from starting in the spring are easily fixed. Most are the result of neglect before storing the lawn mower, but can be corrected with minimal trouble and easily prevented next year.

Gas Left in Tank

One of the most common problems is leaving old gas in the mower. Before storing a mower for the winter, fuel should be drained or you should add a fuel stabilizer. If this was neglected, there is a good chance the mower will not start. In that case, the fuel will need to be drained and replaced.

Once the mower has been refueled, check the oil. If oil is low, add some more. If it looks black or “burnt,” it should be replaced as well.  After checking all the fluid levels, try to start the mower. If it starts, let it idle for a few minutes to let oil redistribute through the engine.

Clogged Filter

If the fuel and oil pass inspection and the mower still won't start, the air filter may be responsible. Dirt, gas, oil, dead bugs, or grass can damage or clog the filter and prevent the mower from starting. Damaged or very dirty filters should be replaced, but if the filter does not look too bad you can clean it. Compressed air can be used to blow particles off a paper filter, and  foam filters can be washed in water with grease-cutting soap.

If you suspect the fuel filter and/or fuel lines are clogged, this maintenance can be more easily done while the fuel is drained. Replacing a fuel filter is more involved than cleaning or replacing an air filter, but can still be done at home.

Spark Plug

Check the spark plug next. Spark plugs are inexpensive and relatively easy to replace, so you might want to just change it once a year. However, if the plug is not corroded, you can clean it using a wire brush. When you do buy a new plug, make sure it matches the old one exactly or it might not work with your model of lawn mower.

If your mower doesn't run properly when you try to start it up in the spring, there are a few simple maintenance tasks you can perform to try and get it operating again. Often, checking the fuel, oil, filters, and spark plug will be enough to get your mower running properly again. If attention to these tasks does not fix the problem, it would be a good idea to take it to a service professional for a tune-up.