The Cub Cadet String Trimmer Will Not Start or Operate Until the Choke Is Engaged: FIXED

When the engine has been warmed up, you find that you are unable to put the choke to the off/open position without the string trimmer shutting off. This is despite the fact that the string trimmer has been properly adjusted. On the other hand, you will be able to keep the engine running so long as you keep the choke engaged, either completely or partly.

Locating the source of the problem and finding a solution to it are very necessary steps to take in order to get the most possible performance out of your trimmer.

When there is either an excessive quantity of air or not enough fuel entering the engine of a Cub Cadet string trimmer, it is possible for the trimmer to function with the choke engaged.

This could be the result of a restriction in the flow of gasoline brought on by a dirty carburetor, a stopped fuel filter, a clogged fuel line, a closed fuel tank vent, or old fuel; alternatively, it could be the consequence of an excessive amount of air brought on by a punctured fuel line or a faulty carburetor gasket.

It is necessary to disconnect the wire from the spark plug before doing any kind of repair work. Be on the lookout, and make it a point to take all of the safety measures that are described in the operator’s manual for the Cub Cadet.

outdoorstip Cub Cadet String Trimmer

There are six different explanations for why a Cub Cadet string trimmer can only be used with the choke engaged.

1. Using Outdated Fuel in Your Cub Cadet String Trimmer

If you let the gas in your Cub Cadet string trimmer sit for an extended period of time, the machine may not work properly. This is due to the fact that stale gas may leave behind sticky deposits, which can limit the flow of fuel.

It’s possible that the only way you’ll be able to keep the mower going is by adjusting the fuel-to-air ratio using the choke. This is because combustion requires a certain ratio of fuel to air.

As soon as 30 days after purchasing, gas might start to degrade and become less effective. This can happen very quickly. Spend money on new fuel and use it up within the next month.

The majority of gasoline that is marketed in today’s market contains ethanol, a kind of fuel that draws moisture into the fuel system. The combination of water and ethanol will get separated from the mixture of gasoline and oil. It leaves behind varnish, which might prevent gasoline from flowing freely or lead to the breakdown of components.

Ethanol is not recommended for use in a vehicle with a smaller engine. Never utilize fuels that have a high percentage of ethanol in them. Steer clear of gasoline labeled E15 and E85 since they may contain as much as 15 and 30 percent ethanol, respectively.

A string trimmer manufactured by Cub Cadet has to be fueled with unleaded gasoline that has an octane value of at least 89 and no more than 10% ethanol by volume.

  • Cub Cadet string trimmers with a two-cycle engine: A combination of gas and 2-cycle oil with a ratio of 40:1 is required to be used.
  • Cub Cadet string trimmers with a 4-cycle motor: Gasoline just is required, since no oil should be mixed together with the fuel. The engine oil is refilled by a different fill port than other fluids.

You may learn more about selecting the right fuel for your Cub Cadet string trimmer and how to properly maintain it by reading the following article.

SOLUTION: Clean out your string trimmer’s tank of any stale gasoline. To prevent the gas from becoming unstable, clean the fuel system, and cut down on the amount of moisture it contains, mix new gasoline in a fuel container with an additive such as Sea Foam or STA-BIL.

Put the fuel mixture into the tank that holds the gasoline. You will need to turn on your Cub Cadet trimmer and let it run for about five minutes in order to move the treated gasoline through the system.

If turning off the choke does not result in an improvement in the trimmer’s performance, proceed to inspect the following components:

2. A Blockage or a Puncture in the Fuel Line of a Cub Cadet String Trimmer

Old gasoline often leaves behind gooey deposits, which may adhere to the fuel line and cause the path to become more constricted. The flow of gasoline is impeded as a result.

You could also discover that the gasoline line has a break in it or that it has been pierced, both of which would enable air to be drawn into the fuel line.

In the event that the fuel line becomes clogged or punctured, the driver may be required to utilize the choke in order to adjust the fuel-to-air ratio in order to keep the engine running.

SOLUTION: It is necessary to remove and repair a gasoline line that has been ruptured or obstructed.

3. Plugged Fuel Filter in a Cub Cadet String Trimmer

A blocked Cub Cadet fuel filter is another component that may inhibit the passage of gasoline through the system. It is possible to prevent dirt and other particles from entering the engine and fuel system by using a filter designed specifically for gasoline.

It is possible for the filter to get clogged if it is not changed often enough or if you are using the vehicle on gasoline that is particularly unclean. This prevents an adequate amount of fuel from passing through the filter. It is in your best interest to keep up with the maintenance of your gasoline filter by doing so at least once each year.

SOLUTION: Replace a blocked fuel filter. Inside of the gasoline tank is where you’ll find the filter. Before removing the gasoline tank cap, clean the area surrounding it with a damp cloth to prevent dirt from dropping into the tank.

It is important to make a mental note of the location of the gasoline filter within the fuel tank so that the replacement filter may be put in the appropriate area. Take the filter out of the tank and set it aside.

Hooking the gasoline linen with a clean wire that has been bent works great in order to remove the filter from the tank. It is time to replace the gasoline filter, so take off the old one, connect the new one to the end of the fuel line, and then replace it inside the petrol tank. Replace the gasoline cap in the tank.

4. A Cub Cadet String Trimmer Suffering from a Defective Carburetor Gasket

Because of its susceptibility to wear and tear over time, the gasket that surrounds the carburetor may lose some of its effectiveness over time. When this happens, the component will no longer seal effectively, which will allow more air to enter the system. This will result in the system running leaner than it normally would.

This circumstance occurs when there is a larger concentration of air than is required by the engine, and there is a lower concentration of fuel than is required.

SOLUTION: It is necessary to first remove the linkages and bolts that are fastening the carburetor in order to have access to it. Remove the gasket and the carburetor off of the engine and set them aside.

After installing the brand-new gasket in place of the worn-out one, reassemble the carburetor together with the bolt and the linkages. After the carburetor for the Cub Cadet trimmer has been removed from the machine, you should inspect it to see whether or not it needs to be cleaned.

5. A Cub Cadet String Trimmer That Has A Unclean Carburetor

The string trimmer’s ability to start and continue running is dependent on the carburetor’s ability to precisely control the quantity of fuel that is introduced into the air mixture during combustion.

The accumulation of varnish and deposits in the carburetor might cause it to malfunction, preventing it from delivering gasoline to the engine and rendering it inoperable.

SOLUTION: If you have any mechanical skill at all, taking care of the cleaning of your carburetor should not present you with any challenges at all. In order to ensure that the carburetor is cleaned thoroughly, it must first be dismantled, and then a carburetor cleaner must be used in order to remove deposits that have been left behind by gasoline that has been used in the past.

If, after being cleaned, the carburetor still does not function correctly, you will either need to be able to get a repair kit in order to rebuild the carburetor or you will need to replace the carburetor.

6. Blocked Fuel Tank Vent on a Cub Cadet String Trimmer

A vent has to be installed in the gasoline tank so that air may enter it and bring the internal pressure up to the same level as the surrounding air. If the gasoline tank does not have a vent, a vacuum will be created within the tank, which will reduce the quantity of fuel that can reach the engine.

Because of this, it’s possible that you’ll have to operate the trimmer with the choke engaged. If your Cub Cadet trimmer runs for a time before becoming slow to operate or turning off entirely, this is a solid indicator that there may be an issue with the fuel tank vent.

The gasoline cap must first be removed in order to let air into the fuel tank before the engine will begin to operate more smoothly.

SOLUTION: Adjust the length of the string on the string trimmer until it is parallel to the ground. Remove the cap, but make sure there isn’t any leakage of the gas within. Start the hedge trimmer up and get it going. Check to see that the choke is completely removed from the animal.

If using the trimmer when the choke is not engaged is not only possible but also successful, the cap should be adjusted and the machine should be permitted to continue operating in this manner. In the event that it stops operating, you will likely need to clear the obstruction from the vent on the fuel tank.

Most of the time, the exhaust from Cub Cadet string trimmers comes out via the fuel cap. Replace a defective cap.