How To Clean Chainsaw Carburetor

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Have you been using your chainsaw quite frequently and the carburetor has got dirty, and you need to clean it, but you don’t know how to? If yes, then you are definitely in the right place.

Cleaning chainsaw carburetor is something that every chainsaw user must know how to do. The right way of cleaning a chainsaw carburetor involves cleaning the air filter, cleaning the carburetor’s intake components, cleaning the carb’s needle valves, working the pull cord, and draining the old fuel before adding fresh fuel. Having a clean chainsaw carburetor is important for your chainsaw to perform to the best of its abilities and to extend its life. While you can get the carburetor cleaned by a professional, you can easily do it yourself if you know the right steps.

In this article, you will get to learn all about chainsaw carburetors, how to clean chainsaw carburetor, the symptoms of a dirty carburetor, and more. Stick around to get all the answers that you are looking for.

Why Does the Chainsaw Carburetor Get Dirty

The chainsaw carburetor is a component that mixes air and fuel and provides the air-fuel mixture in the appropriate proportion to the combustion chamber. The air-fuel mixture or also referred to as the “charge” gets combusted in the combustion chamber. It produces a lot of energy to help drive the engine. This process is the same for every internal combustion (IC) engine, including chainsaw engines.

The carburetor in IC engines can end up getting dirty because of the soot produced as the fuel is burnt and mixed with the oil residue. This results in a gummy, sticky substance blocking the carburetor’s passageways. The fuel stored in the tank for an extended period of time (a few months) will also produce a gummy residue, which can block the carburetor’s passageways.

When that happens, the carburetor cannot provide the correct air-fuel mixture to the combustion chamber. This usually results in improper or incomplete combustion, which reduces the engine’s efficiency and speed. Moreover, it also results in your chainsaw losing power and speed.

If you want the chainsaw to keep performing at its best, you should regularly clean its carburetor. Cleaning the carb is usually not that difficult. On most occasions, you do not even need to open/disassemble it completely for cleaning it.

Symptoms of a Dirty Chainsaw Carburetor

There are a few common symptoms of a dirty carburetor are as follows – 

Reduced engine performance

A dirty carburetor will fail to provide an adequate charge to the combustion chamber, which could result in decreased power and less efficiency.

Black smoke

Black smoke coming out of the exhaust is also a common symptom of a bad/dirty carburetor. Black smoke will indicate that the carburetor is delivering more fuel than needed, which can result in excessive fuel burning.

Backfiring and overheating

Backfiring and overheating can occur when the carb delivers a lean mixture to the combustion chamber. A lean mixture has less than the necessary amount of fuel or more than the required amount of air.

Hard to start

An engine that has a bad or dirty carburetor can be hard to start. This is the reason why the required amount of energy isn’t being produced in the combustion chamber.

Cleaning the Carburetor of your Chainsaw, the DIY Way

A clean carburetor is important for your chainsaw to perform to the best of its abilities and to extend its life. While you can easily get your carburetor cleaned by a professional, it is something that you can also do yourself by following a few easy steps. You can easily clean the carburetor by blending the carburetor cleaner with the gasoline and running the chainsaw at a slow speed. You can even use a cleaner like an aerosol Berryman B-12  for cleaning it.

Cleaning the carburetor of your chainsaw will never be a problem if you follow the instructions. The entire cleaning procedure will be a breeze once you grasp the two primary tasks – supply air and fuel to the ignition chamber of the engine.

Once you know the procedure, you will never have to spend time or money visiting your local engine shop for cleaning the carburetor. 

How to Clean Chainsaw Carburetor

You can easily clean the carburetor of your chainsaw using this step-by-step procedure mentioned below:

Step 1: Clean the air filter

When you are trying to clean the carburetor of your chainsaw, you should begin by checking the air filter. A visual inspection will usually be enough to know whether the chainsaw’s air filter is clean or dirty. A clogged air filter could prevent the required amount of air from reaching the air intake component of the chainsaw.

A metallic air filter can be cleaned by immersing it in a high-quality liquid cleaning agent. If the filter is made out of paper or material that could disintegrate in the cleaning agent, the best solution will be to replace it with a new one.

Step 2: Clean the intake components

After confirming that the air filter is fine, or you’ve cleaned it, you should try to start your chainsaw again. If it still does not start, you should proceed by checking the carburetor’s air intake surfaces for a gummy or sticky residue. This thick residue will likely be brown and is often present on the air intake surfaces. In case you spot gummy residue blocking the air intake components, you should clean the components by spraying the surfaces with a decent spray cleaner. You’ll also need to use a brush for removing the gummy residue.

Step 3: Wash and clean the carburetor’s needle valves

If the chainsaw still doesn’t start once you have cleaned the intake components, you should check the carburetor’s needle valves because they can easily get clogged or gummed by propane deposits. This will usually happen when fuel is added to the chainsaw.

Use a carburetor cleaner and a brush for cleaning the needle valves. After you have cleaned the needle valves, you should dry them using a clean them to drain off any remaining agents before reinstalling them.

Step 4: Work the pull cord

Add a few drops of the cleaning agent to the fuel tank before giving your chainsaw’s pull cord a few strong pulls. Remember to give a few pauses in between to give the additives enough time to dissolve the gummy deposits in the carburetor or the fuel lines connected to it.

Although your chainsaw is not running yet, you should pull the cord combined with intermediate pauses. This will move the cleaning agent that is blended with the fuel through the fuel lines and carburetor valves.

Step 5: Add fresh fuel after draining the old fuel

Often, the issue can be caused by old fuel or residue fuel already stored in the chainsaw’s fuel tank for 2–3 months. Stored fuel tends to absorb moisture or evaporate, resulting in a gummy substance that clogs the carburetor and fuel lines. Once you have cleaned the carburetor, you should empty the old fuel from the tank and carburetor. After that, refill it with fresh fuel before you start operating the chainsaw.

If you intend to store your chainsaw for an extended period of time, you should add a bit of fuel stabilizer to the gas tank. Moreover, start the chainsaw shortly so that it can fill the carburetor too. Don’t forget to add it to other stored gas as well.

How to Clean a Chainsaw Carb!

How to Clean Chainsaw Carburetor without Opening/Removing it

Suppose you have not cleaned the carburetor of your chainsaw for quite some time. Thea best way of cleaning it would be to remove it and then open it. After that, you can thoroughly clean it using a cleaning liquid and a brush. However, if you’re regularly cleaning the carburetor and know that the gummy buildup isn’t too much, you can easily clean the chainsaw carburetor without having to disassemble it completely.

To clean the carburetor without having to open/remove it, you will require a carburetor cleaner liquid. The steps to clean the chainsaw carburetor without opening/removing it are-

Step 1: Blend the cleaner with gas

First, you need to blend the carburetor cleaner with the gas in the fuel tank of your chainsaw. It is recommended that you should blend 4 oz. (113gm) of the B12 carburetor cleaner with a tankful of gas. Make use of a funnel for slowly adding the carburetor cleaner into the gas tank.

Step 2: Run the chainsaw at an idle or slow speed

After you have blended the carburetor cleaner with gas, you should start your chainsaw. Let your chainsaw run at low RMPs or idle for a while. This is done to let the cleaner run through the carburetor, the idle engine, and the fuel lines.

The carburetor cleaner will wipe away the gummy residue blocking the components from creating a clean passageway for the air and fuel. As the RPMs start increasing, you should turn down the idle knob.

Step 3:  Clean the Pilot Air Jet

If you’re looking to clean the chainsaw’s carburetor even more thoroughly, you should add a bit of aerosol B12 to its pilot air jet. The carburetor component will serve as the intake mouth. This is usually hidden from sight due to its sensitivity and the potential risks that occur if it gets damaged. You should consult the user manual of the chainsaw to know the exact location of the carburetor’s pilot air jet.

Step 4: Test the chainsaw

For testing the chainsaw, you need to operate it at full speed. If your saw starts easily and continues running at top speed without any hint of power loss or speed loss, then it means you have successfully cleaned the chainsaw carburetor.

How to Clean a Corroded Carburetor

Cleaning a corroded chainsaw carburetor is generally more difficult and time-consuming, as you need to disassemble it and then scrub its components.

person disassembling chainsaw components

For cleaning a corroded carburetor, you should prepare a diluted mixture of carburetor cleaner with water. After that, clean the air filter before removing/disassembling the carburetor. Now, scrub and wash the individual parts with a brush and the cleaning mixture. Lastly, you should dry out the washed parts using a clean cloth and assemble the carburetor. Reinstall it and your chainsaw will be ready to be used once more.

If you feel that removing and disassembling the chainsaw’s carburetor is tricky for you and that you might damage the saw, you shouldn’t hesitate in asking a professional for help. 


Can Sea foam be used for cleaning a chainsaw carburetor?

Yes, you can use Sea Form Spray for cleaning the carburetor of your chainsaw effectively. Sea Foam Spray comes with petroleum cleansing solvency and adds lubricity to various components of the chainsaw carburetor. This makes it a fine cleaning agent for chainsaw carburetors.

How can I clean a carburetor without needing to remove the carburetor?

Spray with a carb cleaner liberally while trying to direct the cleaner into the jets. Now, leave it to soak for a while. Make use of an air line or a can of pressured air for blowing through the jets. Repeat the previous step and this one until you can no longer see any gunge.

How do I know if my carburetor has gone bad?

If your carburetor is damaged or old and not functioning properly, you will know that your carburetor has gone bad. To test the carburetor, you should remove the air filter, slowly pour a teaspoon of fuel, and pull the starter rope. In case the engine starts momentarily and eventually dies, the carburetor is why the chainsaw won’t start.

What is the best thing that you can use for cleaning the chainsaw carburetor?

The popular WD-40’s Fast-Acting Carb/Throttle Body Cleaner is arguably the most popular carburetor cleaner on the market. If you are looking to clean the carburetor in just a few minutes, this product will deliver top-tier cleaning within a few minutes time. Further, there will be no dipping or scrubbing involved.

Is vinegar a good option for cleaning the chainsaw carburetor?

Can I use vinegar for cleaning the chainsaw carburetor is a common question that most chainsaw users have. However, it is important that you shouldn’t use a non-corrosive cleaner that doesn’t harm or degrade any rubber or plastic pieces on the carburetor. You should not be using vinegar as the acetic acid makes the metal susceptible to rust.

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Hi, I'm Mike - but my friends call me Backyard Mike. I'm the founder of this website, and I'm addicted to outdoor power tools. I love to work with wood and share my knowledge here on this website with you. You can find more about me here.