Zero-Turn Mower Only Operates with Choke Engaged!

When you turn the choke off, your zero turn will start but quickly perish. The engine will continue to operate only if the choke is fully open or partially closed.

The only time the choke should be engaged on a zero-turn lawn mower is when the engine is receiving too much air or not enough gasoline.

A dirty carburetor, low gas quality, a clogged fuel filter, a broken fuel pump, a leaking gas cap, a kinked or broken fuel line, or a malfunctioning carburetor gasket could all be to blame.

Turn off the mower, take out the key, and disconnect the spark plug wires before working on it. Put the brakes on until the engine has cooled down. The manual that came with your equipment should have a checklist of things to remember to keep you safe.

Your zero-inability turn’s to function without the choke being engaged is due to the following:

  • Run-out of gas
  • Antiquated fuel
  • Carburetor clogged with grime
  • Blockage in the fuel line
  • Faulty gas pump
  • An obstruction in the fuel filter
  • Faulty gas cap
  • There’s just too much space between the walls
  • Ruptured gasket in the carburetor.
  • Damage to the fuel line

choke knob

Top 6 Reasons Why A Zero-Turn Needs The Choke Engaged:

Used Gas in a Zero Turn Mower

It’s possible you don’t know that after 30 days, gas starts to degrade. It’s vital to only buy as much gas as you’ll use in that time frame.

Both rapid gas consumption and the usage of the appropriate gas are crucial. As a general rule, unleaded gasoline with an octane value of 87 or above and no more than 10% ethanol content can be used in gas-powered zero-turn mowers.

Never fill up with gas that has more than 10% ethanol in it. Small engines shouldn’t run on ethanol, and if they do, it should be used sparingly.

Plants may be used to create a fuel called ethanol. It is bad for the zero-turn vehicle’s fuel system and engine because moisture is drawn to it.

As the ethanol and water evaporate, they can leave behind a varnish that clogs gasoline filters and corrodes fuel system components. With time, it also splits from the gas and sinks to the bottom of the storage tank. The engine gets very hot with this mixture.

The fuel tank must be drained. It’s recommended that you use a petrol siphon pump for this.

To keep the gasoline system clean and dry, try filling the tank with new gas that has been treated with a fuel additive. Sea Foam Motor Treatment is a product I regularly use. The positive effects of Sea Foam on your vehicle’s fuel system and engine are discussed in greater detail here.

Damage to the Fuel Line of a Zero Turn Mower

When a fuel line is punctured, air is sucked into the line and into the engine. A blockage in the fuel line can also reduce the amount of fuel reaching the engine.

Either of these problems could be why your mower won’t start unless you turn the choke on.

Checking the fuel lines is the solution. Track the fuel line’s outlet up to the carburetor. The fuel system should be inspected for any holes or splits that can let air in.

Next, examine the fuel line for any signs of obstruction that could be limiting fuel flow. The fuel shut-off valve must be used first to stop the fuel supply. The next step is to cut off a length of the fuel line and pour the petrol out into a storage tank.

Once you’ve re-established fuel flow, check that the fuel line is unblocked and that fuel is flowing freely into the storage tank. Turn off the fuel and take the fuel line out of the zero-turn if it is not flowing well.

A carburetor cleaner sprayed down the line should help get things moving again. Then, use compressed air to clear out the obstruction. As often as required.

If the gasoline line is too clogged or damaged to be cleaned, or if you locate a puncture, you should replace the damaged portion with a new one of the same diameter.

A Zero Turn Mower with a Leaking Carburetor Gasket

The gasket protecting the back of the zero-turn carburetor is susceptible to wear and eventual failure. When this happens, the seal breaks and air gets in, making the engine perform poorly due to a lack of fuel.

By contrast, when the air-to-fuel ratio is too high, the engine is said to be running lean. If the carburetor gasket is leaking, additional air will be sucked into the engine, necessitating the use of the choke.

Access the carburetor by dismantling the nuts and connections holding it in place. Take off the gasket and carburetor.

After replacing the gasket, the carburetor, bolt, and links can be reattached. While the carburetor is removed from the mower, you can inspect it to see if it needs to be cleaned.

Zero-Turn Mower Fuel Filter Clogged

A fuel filter is a tiny component installed in the fuel system to prevent debris and other contaminants from entering the fuel system and damaging the engine.

As a matter of routine maintenance, this component requires replacement every year. If the fuel filter becomes clogged, the flow of gasoline to the engine may be reduced.

If you’ve had to cut back on fuel, you may need to adjust the air-to-fuel mixture with the choke.

The answer is to disconnect the fuel filter and replace it with a new inline fuel filter. The filter housing should have an arrow pointing in the right direction.

When installing the filter, make sure the arrow points in the direction of fuel flow.

A Zero Turn Mower with a Filthy Carburetor

To get the zero-turn engine going and keep it going, the carburetor controls how much gasoline is mixed with air to create combustion.

Old gas can clog fuel passages and cause internal components to stick, which leads to a carburetor failure. Either cleaning or replacing the carburetor will be required to restore proper operation.

If you are mechanically inclined and don’t mind fiddling with tiny parts, you should be able to clean the carburetor on your own by following these steps.

The carburetor may need to be rebuilt or replaced if it still doesn’t operate after being cleaned.

If you don’t feel up to cleaning your mower yourself, take it to a small engine dealer.

A Zero Turn Mower with a Leaky Gas Cap

The gas cap is perforated so that air can flow through and help to ventilate the gasoline tank. If the gasoline tank cap fails or becomes obstructed, the tank will develop a vacuum.

Because of the broken cap, the carburetor will only receive a little supply of fuel.

SOLUTION: Loosening the gas cap and letting air into the tank may help you determine if the gas cap is broken. If you can adjust the choke but the engine still running, it may be the cap.

If you want to be absolutely sure that the cap is bad, you should try to duplicate the situation. While the engine is running, tighten the cap.

If it starts running slowly and you have to use the choke to keep it going, but the problem goes away as you loosen the cap, the choke is probably the culprit.

Is Your Zero Turn Mower Still Giving You Trouble?

A zero-turn mower can have a wide variety of malfunctions. It’s irrelevant which brand you buy.

Some zero-turn mowers have better components than others, such as larger filters, more powerful engines, and more durable spindle housings, but eventually even the best of them may fail. It’s possible that some people just don’t have the same rate of problem development as others.

I compiled a list of typical issues with the zero-turn to help you isolate the source of the problem. In this manual, you’ll discover information on how to fix common difficulties including the engine dying on a turn, smoking, vibrating, not starting, and not cutting properly.

Learn more about the most frequent issues with zero-turn mowers by reading my guide. Tips for Correcting It

If you’re not confident in your ability to troubleshoot or repair your zero-turn mower, it’s probably better to have a professional technician have a look.

You may get your mower serviced by taking it to a dealership if you need help with it. There could even be a lawnmower repair business nearby staffed by experts in the field of small engines.