How to Troubleshoot a Mower Engine
- 1). Inspect your lawn mower visually before you even grab any tools. Make sure there are no broken hoses, corroded wires, missing cords, severe dents anywhere or any other obvious damage to the mower. Also check the gas tank to be sure it has fuel in it and it's not leaking. Wipe out the vents and intake fins on your mower.
- 2). Check the engine oil. If it is very thick and/or dirty, change it. Make sure there is no water in the fuel tank. If the oil and fuel look okay but they are older than two or three months, change them.
- 3). Inspect the engine air filter and replace it if it's dirty.
- 4). Open the mower and look at the spark plugs; if they are dirty, replace them.
- 5). Check the battery for power with a multimeter. Replace it if needed. If the engine won't start but the battery is good, use a wire to connect the positive (red) terminal of the battery to the mower starter switch where it is marked with a positive sign or an "s." If the mower starts this way, replace the starter switch.
- 6). Take your mower in to have the carburetor serviced if the mower starts but turns off after a few minutes, if the mower sputters a lot or if the engine floods when you start it.
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