Why Does My Lawnmower Start and Quickly Die?
If your lawnmower starts but quickly dies, there are a few parts that could be causing this problem. We will take you through which parts to inspect, what you will need to look out for, and the steps necessary to get your lawnmower back up and running again. Keep in mind that lawnmower models can differ, so use these troubleshooting tips as a general guide.
What to Check if Your Lawn Mower Starts and Quickly Dies
Problem 1: Loose Carburetor Plate
If the lawnmower’s engine fires up but then dies almost immediately after, it could be an issue with the carburetor. A small engine needs a continual supply of fuel and air to start successfully and continue to run. The carburetor regulates the amount of fuel and air to start and run the small engine. The carburetor regulates the amount of fuel that enters the engine and mixes the fuel with air into the perfect ratio needed for combustion.
To check this part, start by removing the air filter. You should now have access to the carburetor. Use your hand to wiggle the carburetor and see if you can shake it back and forth with your hand. If it appears loose, you will need to tighten the screws that hold it in place.
If these screws are already tight, remove the carburetor and tighten the screws of the carburetor plate.
If these screws are already tight, your next step is to remove the top cover and recoil to access the bolts that connect the intake tube from the carburetor to the head. Tighten the bolts and reassemble the carburetor, recoil, and top cover.
Problem 2: Restricted Carburetor or Carburetor Bottom Nut
Again, to access this part, you will need to remove the air filter first. Clamp a vise grip onto the gas line to avoid any leaking gas and then disconnect the gas line from the carburetor.
You can now remove the carburetor from the engine and remove the bottom nut from the carburetor bowl.
Next, remove the bowl and pull the pin and needle from the float. Clean the ports of the bottom nut and carburetor as well as the float, needle, and pin. Drain the bowl with carburetor cleaner and reassemble all the parts once everything has completely dried. Now it is time to reinstall the carburetor back onto the engine, ensuring all the screws are tight.
If you have taken all of these steps and are still experiencing a lawnmower that starts and quickly dies, try checking the condition of your air filter and fuel filter. These are other common wear parts that should be checked regularly. If you suspect your carburetor is defective, it is a good idea to get it replaced as soon as possible. If you are in need of OEM lawnmower replacement parts, use your model number to search eReplacementParts.com.