The carburetor might be clogged. A clogged carburetor is most commonly caused by leaving fuel in the lawn mower for a long period of time. This sticky fuel can clog up the carburetor and cause the engine to stall. If the carburetor is clogged, try cleaning it with carburetor cleaner.
How do I fix my lawn mower from sputtering?
Remove the cap and check the gas tank for evidence of water (if you see the liquid separating or looking like two different colors). If there is water in your tank, siphon or drain it, then add new gas. After old gas in the line works its way through the mower’s engine it should stop sputtering and run like new again.
Why does my lawn mower keep rev up and down?
A lawnmower that hunts and surges may be experiencing something as simple as an airflow issue. If the air that the engine requires to run is blocked, especially sporadically, it can cause the engine to slow down. When the blockage moves or clears, the engine may suddenly rev up in response.
Why does my lawn mower sound weak?
Other possible causes include: 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.
What causes a lawn mower to run sluggish?
Maintenance lapses become evident when the mower turns over slowly or begins to falter at start-up. The fault could be a dirty spark plug, air filter or carburetor, or it could be related to the quality of the gasoline used. Slow starting can also be the result of a failure to clean the blades.
Will a bad spark plug cause a lawn mower to stall?
A bad spark plug often causes an engine cylinder to misfire or sound like it’s struggling. The engine might even stall out completely while you are mowing. You may also notice that it becomes increasingly more difficult to restart the mower each time that it dies.
How do you fix a rough idle on a lawn mower?
If your lawn mower cuts out, smokes, idles poorly, vibrates or runs erratically, it could need a good tune-up to replace the spark plug, oil and air filter. Or the problem could be with the lawn mower’s fuel system. Rebuild or replace the carburetor if the engine isn’t getting a good supply of fuel.
How do I fix my surging?
Inspect the vent on your gas tank’s cap and clean it if it’s dirty. Drain the gas tank, clean the gas bowl, and add a fresh batch of fuel. Or you can inject fuel cleaner to clean the fuel line. After changing the fuel or injecting fuel cleaner run the lawn mower as usual.
How do you fix a surging idle?
Turn the engine off again, and reattach the air intake duct work to the throttle body. Start the engine and rev and hold to 1,500 to 2,000 rpm until no white smoke is coming out of the exhaust pipe. Cleaning the Idle Air Speed Control Valve with aerosol throttle cleaner can often solve an idle problem.
Why does my car rev up and down while idling?
The idle is controlled by the idle air control valve and if it cannot keep the engine idling it will keep trying to rev the engine up to compensate. A vacuum leak, sensor that has failed, or an EGR system malfunction could potentially be the cause of the erratic engine you’re experiencing.
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.
Why does a lawn mower run rich?
A restricted air filter will cause an engine to run too rich. Remove the filter and check it then. If you have to prime the engine first to get it started, it could also be the float stuck. In the case of a diaphram carb, it could be the needle is stuck in the open position.
How do I clean the carburetor on my lawn mower?
Step-by-step guide to cleaning lawn mower carburetor
- Safety first. …
- Check to see if the problem really is the carburetor. …
- Remove the outer casing and air filter. …
- Unbolt the carburetor and remove it from the fuel line. …
- Unbolt the bowl and clean the nut. …
- Replace the needle.
How do I get more power out of my lawn mower?
How to Get More HP Out of a Lawn Mower Engine
- Remove the flywheel housing from the top of your engine. …
- Unscrew the bolt holding the governor flap next to the flywheel with the proper sized wrench. …
- Inspect the muffler. …
- Fill the gas tank on your mower with a high octane gas. …
- Maximize the air flow.
What does a bad spark plug look like lawn mower?
Its center electrode should have a flat top. If its top is rounded, then the spark plug must be replaced. Look for cracks or chips in the spark plug’s porcelain sheath as well as pitting on its firing electrode.
How can I speed up my lawn mower?
- The engine pulley. Lawn mowers always come complete with belt systems that can be made quicker by simply changing the size of the pulley. …
- The governor. The governor is designed to control fuel flow to the mower engine. …
- The air filter. Clean your lawn mower’s air filter as often as you can. …
- The engine oil.