Last Updated on March 8, 2021 by Appliance Repair Assistant
Start your lawn mower fast! Lawn mower will not start up. The lawn mower has been sitting since last summer. Mower will not start after 3 rope pulls. What causes this? Old gasoline, clogged air filters, and spark plug issues are the 3 things that you need to be aware of. Here are some how to fix tips to get a lawn mower running again.
Check this first… Is fuel switch turned to the ON position? Check choke/primer before starting your mower. Is push handle depressed? Be sure you have fuel in the gas tank. Is the engine oil at the proper level? A 4 stroke engine has a seperate area to add oil, a 2 stroke engine will have the oil mixed with the fuel, so depending on your mower, be sure you have the correct combination.
Most issues with lawn mowers not starting are problems with the fuel getting old, a dirty spark plug, or the air filter is clogged and the air flow to the engine is restricted. There may also be an issue with the carburetor, the fuel filter, or blocked fuel lines.
To attempt to force a lawn mower to start, you can try using engine starting fluid spray and spraying it into the air filter. Once the starting fluid is sprayed into the air filter, attempt to start the mower. If it starts up and stays running, then your mower is working and you are good to go. If the mower starts but does not stay running, there is most likely a problem with the gas, spark plug, or air filter. Please read on for more information below.
3 Tips – Lawn Mower Will Not Start:
1. Old Fuel In Lawn Mower – Use clean fuel in mower.
The lawn mower needs clean gas to run properly. Drain out the old gas if it has sat for long periods of time. (Should be a screw on the carb to drain out gas) If you have added a fuel stabilizer before winter, the old fuel should be usable. If not, add new fuel to the lawn mower gas tank and attempt to start it. If you have good clean fuel in the mower and it still does not start, go to the next step.
Lawn mower won’t start? Fuel flush!
2. Lawn Mower Spark Plug – Check spark plug lead and spark plug positioning.
Be sure the spark plug is clean and tightly connected. Also check spark plug gap is correct. Always check the spark plug lead. Be sure the lead is tight and properly fitted on top of the spark plug. The spark plug itself may not be positioned properly in the engine. Check it with a spark plug socket to be sure it is clean and positioned in the proper position. If the spark plug is dirty, you can clean it off or easily remove and replace the spark plug. A spark plug costs around $10 US dollars, so it is cheap to replace. If you have a good spark plug in the mower and it still will not start, go to the next step.
3. Lawn mower Air Filter – A dirty air filter can cause your mower to not start.
The air filter in your lawn mower needs to be free of dirt and dust to run as designed. Locate the air filter on your lawn mower. Visually check it to be sure it is clean. If not, remove the air filter and clean it. Take it out and wash it in a bucket of hot soapy water then rinse and let it dry. If the air filter is deteriorating, replace it with a new air filter. Once you have a clean air filter, install it in the mower. After these 3 lawnmower tips, the mower should start up! If not keep reading below…
Troubleshoot Your Lawn Mower Not Starting
More Reasons A Mower Will Not Start:
– Be sure the fuel switch is turned ON.
– Check choke/primer to be sure the mower will start.
There may also be an issue with the carburetor, oil level, the fuel filter, or blocked fuel lines.
– Check that the oil is filled to the proper level.
– The fuel lines may be clogged and no fuel is reaching the engine.
– Check the fuel lines and the fuel filter and replace the filter if needed.
– The carburetor might be clogged and fuel flow may not be possible.
– Clean or rebuild the carb to let fuel flow as needed.
– If you have a Honda mower, then make sure oil is at the right level.
NOTE: These tips to start a mower can also be used to start an ATV or ATC.
Do you have any tips or tricks to help a mower start up? Please let us know in the comments below.