Why Does My Chainsaw Smoke: Reasons And Tips To Stop Chainsaw From Smoking

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Do you constantly find yourself wondering why does my chainsaw smoke? If you do, then you’re not alone. Many people face the issue where their chainsaws start smoking. There are many reasons for that and many tips to help you avoid that, all of which you will get to know in this article.

Reasons why your chainsaw smokes when cutting

Bad oil-gasoline mixture

One of the predominant reasons you may think why does my chainsaw smoke when cutting is a bad oil-fuel mixture. The mixture needs to be prepared carefully, taking into account appropriate percentages. Remember the indications of the manufacturer when starting out, as there are different proportions for different brands. For instance, consider 2% (for Stihl) to 4% (for other brands) of oil and the remaining part as gasoline. If the chainsaw smokes when running, it might be due to the mixture being wrongly dosed, causing engine overheating.

man holding a chainsaw smoking

Remember, white smoke from bad mixing can cause a further breakdown, damaging the entire mechanism. It is important to consider the problem and fix it at the first signs.

Smoke due to segment issues

If the chainsaw smokes, it might be due to a segment problem. Examine the engine and notice if the ring is damaged or broken. If you notice a lack of horsepower in use, it might be because of the segment. It needs to be replaced immediately and correctly. This component frequently wears out, so it shouldn’t be difficult to find from manufacturers. Fix this issue and see if the smoke still persists. 

Dirty muffler

As the name suggests, the primary function of the silencer will be to reduce engine noise. If you notice why does my chainsaw smoke so much, the muffler might be dirty because of carbon build-up. When igniting, the engine will start producing smoke. You can easily clean the muffler with a mild detergent. However, it is recommended that you should replace it and prevent the problems from recurring in the future.

Clogged air filter

Similar to the muffler, the air filter could potentially be clogged. A clogged air filter leads to white smoke during usage. The air filter in your chainsaw is tasked with cleaning the air before it mixes with the fuel. 

If it is dirty, it’ll send not enough air into the fuel mixture, which ignites if the cylinder is too hot. Overheating leads to smoke. You must spend time cleaning up the filter with soapy water and then rinse it with cold water. Once it is dry, simply replace the filter and the smoke will be gone. Make sure to change the filter once every year as it’ll help in better maintenance of the chainsaw.

Chainsaw chain

Sometimes, mechanical issues could occur in your chainsaw, leading you to wonder why does my chainsaw smoke while running. It can happen due to a problem with the chain. You should remember to analyze your chainsaw chain and if you notice any damage, get it repaired. Your chain shouldn’t smoke as it is a sign of danger. 

If you notice any smoke from the chain, look for chain lubrication. If the lubrication is insufficient, the chain will heat up very quickly and the friction will be too strong. This will result in smoke production.

If you notice this issue, stop the chainsaw immediately. Clean up the lubrication system and ensure that the chain is receiving enough lubrication to work properly.

Carburetor needle

Thinking why does my chainsaw smoke so much white smoke despite repairing, then check the tightness of the carburetor needle. If there are any leaks at this level, then smoke will be the result. 

Carburetor needles work in a similar way depending on the brand. If the carburetor needle has leaks, or it is perforated, there will be problems in use. It is necessary to replace the damaged part.

Poorly adjusted idle

Sometimes, you might notice smoke coming out of the exhaust even if the chainsaw is idle. If it happens, it is time to adjust the chainsaw’s engine idle speed. Exhaust smoke is an indication that the chainsaw is idling at a too rapid speed. To lower the idle speed, locate the low-speed adjustment screw and simply turn it clockwise until the idle speed slows. Turn the screw backward 90-degrees and increase the throttle for ensuring that the engine accelerates smoothly. Adjusting the idle speed will fix the expulsion of smoke from the exhaust. If needed, you can adjust the idle-speed adjusting screw as well.

Guide bar issues

If you have to ask yourself why does my chainsaw bar smoke while running, it might be due to the guide bar. The culprit will be easy to diagnose. Check the guide bar oil reservoir for ensuring that it contains enough oil to cool and lubricate the chain. Ensure that the guide bar doesn’t run dry.

If the reservoir contains oil, run a quick test for ensuring that the oil exits the reservoir and reaches the chain. Point out the tip of the chainsaw blade at a paper or light-colored surface. Allow the chain to run at full throttle for around 30-45 seconds. Examine the surface and look for a light line of oil drops, proving that the oil is coming out of the reservoir. Lastly, check the tension on your guide bar for ensuring that it isn’t adjusted very tightly. If you aren’t able to advance the chain manually, slightly loosen the chain.

Simple tips to prevent chainsaw smoke

It is common to have a chainsaw smoke when cutting if you don’t maintain your chainsaw properly. You must maintain it when it is being used and when it isn’t being used. Maintenance will keep your chainsaw from getting clogged by debris, while also ensuring that the cutting mechanisms work effectively.

Here are some of the simple tips that you must keep in mind to prevent your chainsaw from producing smoke –

Keep the chainsaw sharp

You can easily do that by keeping the chain filed by a file and a file gauge. The file gauge ensures that each tooth is filed at the right angle and the correct depth.

Avoid over-tightening the chainsaw chain

Never over-tighten the chainsaw chain and always have the right tension. If your chainsaw chain is too tight, it’ll cause the chain to overheat, which will lead to smoke.

Break in new chains before use

New chainsaw chains must be soaked in bar and chain oil for many hours. This will make sure that all the points in the chain are properly lubricated. This prevents the build-up of frictional heat in the chain.

Keep the filter clean

Keeping the air filter clean will help keep the airflow in the engine strong and maintain consistent combustion. The air filter is essential in keeping dirt and other unnecessary stuff out of the carburetor. This will prevent one of the leading reasons for chainsaw producing smoke.

Chainsaws will be less likely to produce smoke during operation if you clean them after use. Further, maintain them properly before starting and when not in use. Otherwise, the performance and lifespan of your chainsaw will be diminished through neglect.

Why does your Stihl chainsaw smoke? 

There are instances people buy costly Stihl chainsaws, don’t maintain them properly, and wonder why does my Stihl chainsaw smoke. Smoking in a Stihl chainsaw can be a potential issue the first time you run it. However, it can still be something to keep in mind after a few uses. A chainsaw can start producing smoke due to many issues if the chainsaw isn’t maintained well. Here are some of the reasons why your Stihl chainsaw starts producing smoke regardless of how long you’ve been using it.

man cutting logs using a smoking chainsaw

Issues with chain/guide bar 

A chainsaw chain or guide bar may start overheating if not managed properly. It might either be due to airflow issues or due to excess chainsaw tension. If you continue using the chainsaw when it is overheating, it could potentially cause the engine or pistons to break.

Excessive oil

If you have smoke coming out of the engine, then it indicates an excessive amount of oil in the chainsaw. An abundance of smoke from the chainsaw is a sign that the oil-gasoline mixture in your chainsaw isn’t proper. You might have added an excessive amount of oil. Make sure that you are mixing the right amount of oil and gasoline, depending on the instruction manual. The manual will dictate the amount of mixture to be added. Empty the fuel tank of all the oil and gasoline, before filling the tank with the newly mixed mixture. After putting the new oil, use the chainsaw again.

If your chainsaw starts producing smoke from the exhaust when you start it, you should immediately shut down the chainsaw. Don’t continue using it as it could lead to an accident. You should stop it if the smoke doesn’t clear out within a few moments. Shut it down completely and examine the reason and source of the smoke. Then, troubleshoot the cause.

Chainsaw Troubleshooting: Why Is My Chainsaw Smoking? | eReplacementParts.com


Why does my chainsaw smoke when running is a common problem that many chainsaw users face. However, it is also a problem that can be easily avoided. All you need to do is follow the tips and measures mentioned above and maintain your chainsaw.

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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.