weed eater only runs on choke

Weed Eater Only Runs On Choke – SOLVED

You’ve come to tidy up the edges of your garden only to find that you have a problem with your weed eater. One of the most common issues is that the weed eater only runs on choke but there are several ways this can be addressed. In this article, we are going to look at how to repair a weed eater engine that only runs on choke.

Before we get into the nitty gritty of what might be causing your problems, it is important that we understand the role of the weed eater choke.

The power system of a weed wacker is incredibly delicate and intricate, there are several components that make up the fuel and engine system and if one of them is out of whack, this can mess up the entire thing. The weed eater choke is a valve which is located on the air intake of the engine in a gas weed eater. It is used to reduce the amount of air that gets into the engine, particularly on a cold start.

When the choke valve is shut off, this creates a much richer fuel and air mixture which is imperative when the engine is turned on for a cold start. This is because this fuel-heavy mixture much more easily combusts when it reaches the combustion chamber. After getting the engine started, you are then able to reopen the choke valve and return to the normal amount of airflow.

The weed eater choke lever can either be on or off, when it is in the on position this means that the valve is closed and air cannot get into the engine. Conversely, when the choke lever is off, normal air flow can take place.

Potential Issues

If you have ever found yourself with a weed eater that runs for a while then dies, you will know how frustrating it can be. When looking at how to fix trimmer problems relating to the equipment only running when the choke is on, there are several potential issues:

  • Blocked gas cap
  • Damaged fuel line or fuel filter
  • Clogged or damaged carburetor
  • Crankshaft or piston problems

Troubleshooting: Weed Eater Only Runs On Choke

One of the most critical points that must be addressed is that your garden trimmer requires a significant amount of upkeep. It is essential that you carry out regular weed eater maintenance as this will likely prevent a lot of common problems. If you ensure that this maintenance schedule is adhered to, you will likely have a tool that will last you many years.

In any case, there is always the risk of issues so if your weed eater only runs on choke then you may wish to consider the following.

Check The Gas Cap

One of the first issues that you will need to check when trying to solve this problem is to look at the gas cap. As the trimmer starts up and only runs on choke, this could be related to the valve in the gas cap.

To investigate whether this is the issue, you will need to start your weed eater before half removing the gas cap. You don’t need to remove it entirely as the point of this is to see if the greater airflow improves things and removing halfway is more than enough.

Once you’ve got it open halfway, turn the choke off and see where you end up. If the problem persists, then it is likely that the issue is not with the gas cap. However, if the weed eater doesn’t pack up then it is likely that the gas cap is clogged or dirty.

This is a pretty simple fix and involves nothing more than simply removing the gas cap and giving it a good clean. You can do this with warm, soapy water making sure that you give it a good rinse and allow it to dry fully before putting it back. However, sometimes, the gas cap can be extremely blocked and in this instance, you will be left with no other option but to replace it.

Install New Fuel Lines And Carburetor

If the fuel lines of your weed eater are not in full working order then this can affect the level of fuel that the engine is receiving. These lines are connected to the carburetor which is the part of the system that delivers fuel and air to the engine.

It could be that the fuel lines are damaged or, similarly to the gas cap, could become clogged. Furthermore, there could be an issue with the fuel filter becoming blocked, which could have a similar effect. In this instance, you will once again need to clean these components. In the worst cases, the fuel lines and filter may need to be replaced.

If you are going to replace the fuel lines, it is vital that you first drain the tank of all fuel. Once you have done this, using long, thin pliers will aid you in removing the filter and the fuel lines. You will also need to detach the fuel lines from the carburetor end which will entail removing the cover plate.

When you have successfully removed the old parts, you can install the new ones ensuring that the fuel filter is put into place before using the weed eater.

At this point it is always worth checking the carburetor as there is a very good chance that this could be the culprit. In the best cases, it is a simple matter of cleaning the carburetor. As we have already mentioned, good weed eater maintenance is essential and regular cleaning of all parts will help your equipment to function properly. In the case of the carburetor, a special cleaning solution is required to do the job correctly.

In addition to this, you may need to check that the seals on the carburetor are not damaged or clogged with debris. This part can be totally removed for maintenance but if it is damaged beyond repair, then it can also be easily replaced. Alternatively, you might use a carburetor rebuild kit which you can pick up at almost any garden or DIY store and will contain any replacement parts that you may need.

Seek Professional Help

As much as we may try, there will likely be times that the weed eater gets the better of us and we simply cannot solve the problem at home. In these cases, it is vital that you take your trimmer to be serviced by a professional. Attempting complex repairs by yourself may cause further damage and ultimately result in you having to replace the entire weed eater.

At times, especially for people who are using an older model, the repairs may end up costing more than a replacement. In this case, unless you are very attached to your weed eater, it might be time to upgrade to a newer model.

The most common complex issues relating to a weed wacker engine that only runs on choke is to do with the piston or crankshaft.

Weed Eater Only Runs On Half Choke

If your weed eater is only running on half choke then you will need to address the issues that we have already discussed in this guide. To begin with, you will need to look at the gas cap to ensure that it is not clogged or dirty. If it is, a good clean will likely sort out your issues.

Furthermore, you may wish to check the condition of the fuel lines and fuel filter which may need simply cleaning or a complete replacement.

Finally, if neither of the above solve your problem, the issue could be with a carburetor which could be blocked or damaged. Taking it apart with a carburetor rebuild kit to hand is the best way to assess its condition. If you need to, the entire thing can be replaced. If the issues are a little more complex, don’t hesitate to take your tool to a professional repairs person.


A weed eater is a common garden tool that comes in incredibly handy; in fact, many of us would be lost without this piece of equipment. But when you are running a gas weed eater, this isn’t without its problems. Sometimes they can overheat or if your weed eater is only running on choke then there could be several issues including clogged fuel lines, a blocked gas cap or issues with the weed eater carburetor.

Andrew Fisher

Andrew Fisher

Andrew is a dedicated father of three who really takes pride in his lawn and garden. You'll find Andrew behind the scenes of almost everything Edge Your Lawn produces. When he's not helping readers find all the information they need, he's in his backyard working on his lawn and garden landscaping. This year he hopes to build an outdoor deck and sort out his veg patches.

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