Why is my lawn mower surging up and down?

Why is my lawn mower surging up and down?

Airflow Issues. 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 riding mower spit and sputter?

Your riding mower can sputter due to using a bad batch of fuel in the tank, a damaged gas cap, clogged air filters, excess grass under the deck, a damaged spark plug, a clogged carburetor, or water in the fuel tank. These factors tend to cause your mower to lose power, leading to sputtering.

Why is my lawn mower pulsing?

The most common reason for a surging lawn mower engine is a blockage in the fuel supply, but there are other possibilities: Bad gas. Bad spark plug. Dirty / faulty carburetor.

What causes a lawnmower engine to run rough?

A lawn mower will run rough when the air filter is plugged; water is in the fuel tank; old gas causes fuel restrictions in the fuel filter, fuel lines or carburetor; the spark plug is bad; the gas cap is bad; the mower deck is plugged, the choke is set incorrectly or the ground speed is too fast.

Why is my lawn mower not running smoothly?

If the engine starts, but does not run smoothly, it means that the spark plug and ignition system are in order and you need to look elsewhere for the source of the problem. The usual culprit is air intake or fuel system related.

Why does my mower stop after 10 minutes?

As the fuel level drops, a vacuum begins to form in the fuel tank because air can get in to fill the space the consumed fuel occupied. 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.

Why does my lawn mower run for a few minutes then stops?

If you’ve got a lawn mower that runs for 30 minutes then dies, the most common culprits are: a faulty spark plug or ignition coil, blocked fuel delivery, and air supply problems. A variety of parts are involved here, but the first things you’ll want to check out are the spark plug, carburetor, and fuel cap.

Why does my mower keep dying?

The spark plugs are worn or damaged If you find that your lawnmower keeps dying, or keeps stalling while cutting grass, then inspect the spark plugs. Look for signs of damage or wear. Something as simple as a cracked porcelain insulator can mean an electrode has been damaged or burned away.

Why is my mower pulsing?

How do you fix a surging lawn mower?

Check and clean the vent. Surging is also caused by water that got into the fuel. A mower left in a heavy rain or condensation on a hot summer day can choke the engine. Empty the gas tank, properly dispose of the old fuel and try a fresh batch of gasoline.

What causes an engine to hunt and surge?

Engine hunting and surging at idle is usually caused by a fuel delivery, air leak, or governor system problem. Cleaning/overhauling the carburettor, adjustment of the governor, and/or changing the air filer may be required.