A full gas tank and oil reservoir are the essential first steps when checking why the lawn mower won't stay running, but the problem could also be a dirty filter , clogged carburetor, improper fuel mixture, or a dirty spark plug. ... However, you may need a lawn mower specialist to get you back to trimming your grass.
Why does my lawn mower only run for a few seconds then dies?
If your lawn mower starts, runs briefly, then dies these are the four most common reasons that's happening: Dirty carburetor / clogged carburetor bowl . Old gasoline that has gone bad . Dirty or defective spark plugs .
How do you fix a lawn mower that won't stay running?
Loose, Dirty or Disconnected Spark Plug in Your Lawn Mower: Check it out, clean off debris, re-connect and tighten. Dirty Air Filter : Clean or replace. Fuel Not Reaching the Engine: Tap the side of the carburetor to help the flow of gas. If this doesn't work, you might need a new fuel filter.
What does it mean when your lawn mower keeps cutting off?
Impurities in the fuel, from bad or old gas, can stick to the bore, the screen and other sensitive parts inside the carburetor. When this happens, the carburetor will suffocate and the engine will run poorly and often will shut off when it needs more fuel.
Why is my lawn mower starting then dying?
The air filter is dirty or clogged
A clogged or dirty air filter obstructs the airflow to mix with the fuel. Poor airflow causes the lawnmower engine to die in a few minutes after the start. Since the mower often catches dirt and debris from the yard, the filter quickly gets clogged that needs to be cleaned.
Why does my mower only run when I push the primer?
When you prime the engine you are manually adding extra fuel in, so the running issue is most likely related to poor fuel that will not burn unless there is an excess amount present or a fuel deliver issue preventing enough fuel from getting through to begin with.
How do you clean a carburetor on a lawn mower without removing it?
However, you can not spray the carburetor when the engine is off since it cannot do the cleaning without being propelled. All you need to do is to start the engine and spray directly at the center of the carburetor while it is running. Any deposits clogging in the carburetor will easily be removed.
Why does my lawn mower stop running after 5 minutes?
Most lawnmowers have a vented gas cap. The vent is a check valve that allows air into the fuel tank but keeps gas fumes inside. ... After about 10 or 15 minutes, the vacuum will become strong enough that fuel will stop flowing to the carburetor and the lawnmower will die.
Can I just add oil to my lawn mower?
When filling your lawn mower engine with oil, pour in just a little bit at a time, then re-check the level. ... Use only a type of oil suitable for your lawn mower (check the manual when in doubt). Screw the fill plug back into the crankcase. You are now ready to mower your lawn.
Can a dirty air filter cause a lawn mower not to start?
Your lawn mower's air filter guards the carburetor and engine from debris like grass clippings and dirt. When the air filter becomes clogged or too dirty, it can prevent the engine from starting . To keep this from happening, replace paper filters—or clean or replace foam filters—after every 25 hours of engine use.
Why does my lawn mower only run with the choke on?
If your lawn mower only runs with the choke on, check the carburetor . ... The carburetor brings air and fuel together and mixes them in the perfect ratio for combustion before they enter the engine. There are several passages in the carburetor that allow fuel to enter the air stream depending how the throttle is set.
Can you put carb cleaner in a lawn mower?
Use Carburetor Cleaner
Fortunately, you can generally do this without even taking the carburetor out of the engine. Start by purchasing some commercial lawnmower carburetor cleaner, which comes in a simple spray can and will make it easy to clean the inside and outside of the carb.
How long to wait if lawnmower is flooded?
An engine that's getting gas and not starting probably has a flooded carburetor or cylinder soaked with gasoline. Often your nose can make the diagnosis: Flooded engines reek of unburned fuel. Park the mower on level ground, and wait about 15 minutes for the gas to evaporate .
