A flooded lawn mower is a common issue that occurs when too much fuel enters the engine, preventing it from starting. It can happen when you’ve primed the engine too much or tried to start the mower repeatedly without success. I’ve encountered this problem myself, and the good news is, it’s usually an easy fix!
Here’s a step-by-step guide to help you get your flooded lawn mower running again.
1. Recognize the Signs of a Flooded Engine
Before you try to fix the issue, make sure your lawn mower is actually flooded. Signs of a flooded engine include:
- Strong Smell of Gasoline: A telltale sign of too much fuel in the engine.
- Difficulty Starting: The engine cranks but doesn’t turn over, or it sputters and dies quickly.
- Wet Spark Plug: After trying to start the mower repeatedly, the spark plug may be wet with fuel.
2. Wait and Let the Fuel Evaporate
One of the easiest ways to fix a flooded engine is to simply wait and let the excess fuel evaporate:
- Wait for 15-30 Minutes: Let the mower sit with the choke off. This allows the fuel to evaporate, clearing the excess from the carburetor and combustion chamber.
- Try Again: After waiting, try starting the engine again. Make sure to avoid using the choke if the engine is still warm, as this can cause more flooding.
3. Check and Dry the Spark Plug
If waiting didn’t work, you may need to check the spark plug:
- Locate the Spark Plug: Disconnect the spark plug wire and use a socket wrench to remove the spark plug.
- Inspect for Fuel: If the spark plug is wet with fuel, it means the engine is flooded.
- Dry the Spark Plug: Use a clean cloth or paper towel to dry the spark plug thoroughly.
- Reinstall the Spark Plug: After drying, reinstall the spark plug and reconnect the spark plug wire.
Tip: If the spark plug is old or damaged, it might be a good idea to replace it.
4. Clear the Carburetor and Air Filter
Sometimes excess fuel can build up in the carburetor or air filter, which can prevent the engine from starting:
- Remove the Air Filter: Check the air filter for signs of fuel or excessive dirt. If it’s soaked with fuel, replace or clean it.
- Inspect the Carburetor: If fuel is leaking from the carburetor, try draining the excess by opening the carburetor drain plug (if your mower has one). This will allow the excess fuel to escape.
5. Use the Pull Start Method (Optional)
For mowers with a pull start, an alternate method to fix a flooded engine is to pull the cord multiple times to clear out the excess fuel:
- Turn Off the Choke: Make sure the choke is in the “off” position.
- Pull the Cord: With the spark plug still installed, pull the starter cord a few times to help clear the excess fuel from the combustion chamber.
6. Check the Fuel Valve (if applicable)
Some mowers have a fuel shutoff valve. If the valve is left open while the mower is sitting idle, fuel can continue to flow into the carburetor, causing flooding.
- Close the Fuel Valve: Turn off the fuel valve when the mower is not in use to prevent flooding.
7. Try Starting the Mower Again
After drying the spark plug and letting any excess fuel evaporate, try starting the mower again. Here’s how to do it without flooding it again:
- Turn Off the Choke: Only use the choke if the engine is cold. If the engine is warm, leave the choke off to avoid adding more fuel.
- Pull or Turn the Starter Slowly: Start the mower slowly and steadily to avoid flooding it again.
8. Prevent Future Flooding
To avoid flooding your mower in the future:
- Avoid Over-Priming: If your mower has a primer bulb, only press it 2-3 times before starting.
- Use the Choke Correctly: Only use the choke when starting a cold engine. Once the engine is running, turn the choke off.
- Let the Engine Rest: If the engine doesn’t start after a few attempts, wait for 5-10 minutes before trying again to avoid flooding.
Conclusion
Fixing a flooded lawn mower is usually a simple process. Start by waiting 15-30 minutes to let excess fuel evaporate, then check and dry the spark plug if necessary. Inspect the carburetor and air filter to ensure there’s no excess fuel buildup, and remember to use the choke and primer bulb correctly to prevent future flooding. By following these steps, your mower should be back up and running in no time!