How to Clean a Chainsaw Carburetor Quickly. A pro perspective


A clean carburetor is necessary for your chainsaw to perform at the best of its ability and extends its life. Although, you can get your chainsaw carburetor cleaned by a professional. It is something that you can do yourself by following a few easy steps explained in this article.

How to Clean a Chainsaw Carburetor Quickly:

  • Step 1. Clean the air filter: Check and clean the air filter to ensure that the carburetor is receiving the correct amount of air.
  • Step 2. Clean the carburetor’s intake components: Use a spray cleaner to clean your carburetor’s air intake components.
  • Step 3. Clean the carburetor’s needle valves: Wash your carburetor’s needle valves and dry/drain the washing agents.
  • Step 4. Work the pull cord: Pull your chainsaw’s pull cord with alternating pulls and pauses to allow the fuel-cleaning agent mixture to dissolve the gummy residue.
  • Step 5. Drain the old fuel and add fresh fuel: After cleaning the carb, drain the old fuel from the tank and add fresh fuel before operating your chainsaw.

Alternatively, you can also clean the carburetor by blending some carburetor cleaner with the gasoline and running your chainsaw at a slow speed. You can also use a cleaner, such as aerosol B12, to clean the pilot air jet.

The Function of Your Chainsaw’s Carburetor

The carburetor is a device that mixes air and fuel and provides this air-fuel mixture in an appropriate proportion to the combustion chamber. The air-fuel mixture, also known as the “charge,” is combusted in the combustion chamber. It is producing a lot of energy that drives the engine. This process is the same for all internal combustion (IC) engines, including the engine for your chainsaw.

The carburetor in IC engines often gets dirty because of the soot produced as the fuel is burnt and combined with the oil residue. This produces a gummy, sticky substance blocking the carburetor’s passageways. Fuel stored in the tank for an extended period (several months) also produces a gummy residue that can block the carburetor’s passageways.

When this happens, the carburetor fails to provide the correct air-fuel mixture to the combustion chamber. This results in improper or incomplete combustion. It reduces the engine’s speed and efficiency. And results in your chainsaw losing speed and power. If you want your chainsaw to keep performing at its best, you must regularly clean its carburetor. Cleaning the carburetor is usually not difficult. On many occasions, you don’t have to open/disassemble it completely to clean it.

Symptoms of a Bad/Dirty Carburetor, some helpful tips

Some common symptoms of a dirty or failing carburetor are as follows:

  • Reduced engine performance: A dirty carburetor fails to provide an adequate charge to the combustion chamber resulting in decreased efficiency and power.
  • Backfiring and overheating: Backfiring and overheating occurs when the carburetor delivers a lean mixture to the combustion chamber. A lean mixture has less than the required amount of fuel or more than the necessary amount of air.
  • Black smoke: Black smoke from the exhaust is also a common symptom of a failing carburetor. Black smoke indicates that the carburetor is delivering more fuel than required, resulting in excessive fuel burning.
  • Hard to start: An engine with a dirty carburetor is hard to start because the required amount of energy is not being produced in the combustion chamber.

Step by Step Procedure for Cleaning a Chainsaw Carburetor

You can clean your chainsaw’s carburetor using the following five easy steps:

● Step 1: Clean the Air Filter

Whenever trying to clean the carburetor of your chainsaw, start by checking the air filter. A visual inspection is usually enough to know whether the air filter is clean or dirty. A clogged air filter prevents the required amount of air from reaching the carburetor’s air intake component.

A metallic air filter is cleaned by immersing it in a liquid cleaning agent. If the filter is made of paper or material that is likely to disintegrate in the cleaning agent, the best solution would be to replace it with a new one.

● Step 2: Clean the Carburetor’s Intake Components

After confirming that the air filter is fine or you have cleaned it. Try starting your chainsaw again. If it still doesn’t start, proceed by checking the carburetor’s air intake surfaces for a gummy/sticky residue. This thick residue is usually brown and is often apparent on the air intake surfaces.

If you spot a gummy residue blocking the air intake components, clean these components by spraying the surfaces with a spray cleaner. You may also use a brush to remove the gummy residue.

● Step 3: Clean/Wash the Carburetor’s Needle Valves

If your chainsaw still doesn’t start after you’ve cleaned the intake components, check the carburetor’s needle valves because they are often clogged/gummed by propane deposits. This usually happens when fuel is being added to the chainsaw.

Use a carburetor cleaner and a brush to clean the needle valves. After cleaning the needle valves, dry them with a clean cloth to drain off the cleaning agents before reinstalling them.

● Step 4: Work the Pull Cord

Add some drops of a cleaning agent to the fuel tank and give your chainsaw’s pull cord some strong pulls, with pauses in between to allow the additive to dissolve the gummy deposits present in the carburetor or the fuel lines connected to it. Even though your chainsaw isn’t running yet, pull the cord combined with intermediate pauses. This will move the cleaning agent blended with the fuel through the carburetor valves and fuel lines.

● Step 5: Drain the Old Fuel and Add Fresh Fuel

Often the problem is caused by old fuel or fuel stored in the chainsaw’s fuel tank for over 1 or 2 months. Stored fuel absorbs moisture or evaporates, producing a gummy substance that clogs the carburetor and fuel lines. After cleaning the carburetor, empty the old/stored fuel from the tank and carburetor. Refill it with fresh fuel before operating your chainsaw.

If you plan to store your chainsaw for an extended period, add some fuel stabilizer to the gas tank. And start the chainsaw shortly, so it can fill the carburetor as well. Do not forget to add it also to other stored gas.

Cleaning a Carburetor Without Opening/Removing It. Some helpful tips:

Suppose the carburetor of your chainsaw hasn’t been cleaned for quite some time. The best way to clean it would be to remove and open it. Then thoroughly clean it using a brush and a cleaning liquid. However, if you regularly clean the carburetor and know that the gum buildup isn’t too much, you can clean the carburetor without even having disassembled it.

To clean a carburetor without having to remove/open it, you’ll need a carburetor cleaner liquid. This cleaning process is as follow:

● Step 1: Blend the Cleaner With Gas

Firstly, blend some carburetor cleaner with the gas in your chainsaw’s fuel tank. I recommend blending 4 ounces (113 grams) of the B12 carburetor cleaner with a tankful of gas. Use a funnel to add the carburetor cleaner into the gas tank slowly.

● Step 2: Run Your Chainsaw at an Idle or Slow Speed

After blending the carburetor cleaner with gas, start the chainsaw. Let the chainsaw run at low RPMs/idle for a while. This is to let the cleaner run through the carburetor, the fuel lines, and the idle engine.

The cleaner will wipe remove the gummy residue blocking the components to create a clean passageway for the air and fuel. As the RPMs begin to increase, turn down the idle knob.

● Step 3: Clean the Pilot Air Jet

If you wish to clean your chainsaw’s carburetor even more thoroughly, add some aerosol B12 in its pilot air jet. This carburetor component serves as the intake mouth. It is usually hidden from sight because of its sensitivity and the potential risks associated with it if it’s damaged. Consult your chainsaw’s user manual to know the location of its carburetor’s pilot air jet.

● Step 4: Test Your Chainsaw

To test your chainsaw, operate it at full speed. If your chainsaw starts easily and keeps running at top speed without any hint of speed or power loss. It means that you have successfully cleaned the carburetor.

The Best Carburetor Cleaners

There is a wide variety of carburetor cleaners in the market. You can easily find one at a hardware store or online. Some of the best carburetor cleaners in the market include:

  • The WD/40 Carb/Throttle Body Cleaner: This cleaner is famous for its fast cleaning action with no dipping or scrubbing involved, and it comes with an easily replaceable lid.
  • The CRC Carb and Choke Cleaner: This cleaner is VOC-compliant and doesn’t harm any catalytic converters or oxygen sensors that it comes in contact with. It also provides a fast cleansing action.
  • Gumout Jet Spray Carb/Choke and Parts Cleaner: This cleaner is known for its fast action and replaceable cap, preventing the cleaner from escaping when it’s not used.
  • Super Tech Carb Cleaner: This cleaner can easily tackle grime, dirt, and all other kinds of sticky deposits. It’s famous for its well-round cleaning capacity.

You may also inquire from your chainsaw manufacturer to recommend carburetor cleaners because they usually know which chemicals work best on their machine.

Cleaning a Corroded Carburetor

Cleaning a corroded chainsaw carburetor is usually more difficult and time-consuming because you have to disassemble it and scrub its components.

To clean a corroded carburetor, prepare a diluted mixture of carburetor cleaner with water. Clean the air filter, then remove and disassemble the carburetor. Scrub/wash the individual parts using a brush with the prepared cleaning mixture. Finally, dry all the washed parts with a clean cloth and assemble the carburetor. Reinstall it, and your chainsaw is ready to be used again.

Suppose you feel that removing and disassembling your chainsaw’s carburetor is too tricky. And that you might damage it during the procedure. Ask for help from a professional.

Can Vinegar Be Used to Clean a Chainsaw Carburetor?

It would be best if you did not use vinegar to clean your chainsaw carburetor. Using vinegar is a common question I get from many chainsaw users. The reason not to use it is that the acetic acid in vinegar makes the carburetor metal susceptible to rust. As a general rule, you should only use non-corrosive materials to clean a carburetor.

Can Sea Foam Be Used to Clean a Chainsaw Carburetor?

You can use Sea Foam Spray to clean your chainsaw carburetor effectively. Sea Foam spray has a petroleum cleansing solvency. And adds lubricity to various components of the carburetor. It is a fine cleaning agent for chainsaw carburetors.

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