How To Fix A Chainsaw: Common Issues With A Chainsaw And How To Solve Them

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Even the most high-end products can sometimes face issues. Do you agree?

The same applies to chainsaws. Even the best chainsaws can sometimes have bad days where they don’t function as intended. Yes, many modern manufacturers do incorporate features to help the chainsaws overcome common problems. However, the other times you’ll need to solve the issues with the chainsaw. Here, you’ll get to know some of the common chainsaw issues, how to fix a chainsaw and more.

Common chainsaw problems and their fixes

If your chainsaw isn’t starting or if it is giving poor performance, it would be smart to do some troubleshooting. It is important to know some of the most common issues that users experience when starting and running a chainsaw. Moreover, of even more significance is to know the steps to fix these problems. It would be more helpful if you could try to manually fix the issue, otherwise it’ll cause you a fortune.  

Chainsaw is lacking power

In case you feel that your chainsaw is experiencing power issues, you must check different chainsaw components. Check components like a piston, spark plug, cylinder, and muffler for any wear or damage. A damaged spark arrestor, cylinder exhaust, or muffler would prevent the exhaust gases from leaving the engine and reduce engine power.

Crucial parts of the chainsaw may be clogged with carbon, and cleaning the parts can be the solution. You can even replace them if you want to make sure that your chainsaw is functioning most efficiently.

The piston and cylinder will work in tandem to facilitate the combustion and power of the chainsaw. The ring in your piston might have broken and fallen, which would have reduced its ability to create compression. If this happens, the chainsaw won’t be able to run at its best and this will result in a lack of power. 

For repairing this issue, you should bring in a professional for help. These are key components that need the expertise of someone who knows they’re doing.

Old or bad fuel affecting the performance

Gas or fuel goes bad after a month or so. By the time, the alcohol content that it contains as ethanol absorbs a lot of moisture from the air. Fuel that has too much moisture will simply not be able to ignite or combust easily.  Moreover, small engines are not meant to use fuel that has more than 10% ethanol. You should remember to fill your chainsaw’s gas tank with fuel that has an E10 rating or less.

If you feel that old fuel may be gumming up your chainsaw, then immediately fix it. Drain out the tank, fill it in with fresh gas and try to start it again.

Incorrect oil to gas ratio

Almost all chainsaws today come with 2-cycle engines. This means the engine uses a mix of oil and gas combined before pouring into the fuel tank. Normally, most chainsaws come with a 1:50 ratio of oil-to-gas, while a few others use a 1:40 ratio. Stihl, one of the biggest chainsaw manufacturers also recommends the use of a 1:50 oil-to-gas ratio. Your chainsaw’s user manual will let you know what ratio of oil to gas you must use.

In case you’ve combined oil and gas in the wrong ratio, you should drain the entire tank. Then, replace the mixture with the proper ratio.

Spark plug not working

A spark plug that is cracked, dirty, or worn out will not spark and ignite the engine’s fuel. You should check the spark plug and replace it if it has issues. Remove the plug, clean it, and then check the size of the spark plug gap.

It would be smart to consult a professional for help, as a spark plug is a critical component of your chainsaw.

Worn out starter rope

The starter rope on the chainsaw will grow worn after some time and a few uses. When it is on the verge of breaking, it’ll make starting the chainsaw a big challenge.

You can replace the starter rope manually at home. 

For replacing the starter rope, disconnect the spark plug before removing the starter housing at the side of the chainsaw. Then, unwind the old rope from the recoil pulley. Next up, insert the new rope in the pull and secure it with a knot. Then, thread the loose end of the rope through the housing. Attach the pull handle to the rope end that is threaded through the housing. Pull the new rope tightly and then wind it around the pulley about 2-3 times.

Cold engine

Your chainsaw’s engine must be warm if you want to rev it up and get it running. 

If you are trying to start your chainsaw in cold weather and the engine is cold, try to close to choke. This will give the engine a concentrated burst of fuel.

Gas engine idles and stalls

If the sound coming out of the chainsaw isn’t smooth and consistent, your chainsaw likely requires cleaning. You should clean the air filter and spark plug before ensuring that the plug is in its working condition.

Chainsaw chain isn’t moving

If the electric or gas-powered chainsaw’s chain isn’t turning around the bar, it is likely that the brake is stuck. On a few chainsaws, resetting the chain brake can be as simple as pushing on the side cover. Doing that and pushing the chain brake forward while holding the top handle with the other. Do that and you will hear a slight click once the brake has been reset. You can easily do it by yourself and don’t need professional assistance.

Loose chain ratting

If your chainsaw chain turns around the guide bar but hangs loose or rattles when it turns around, adjust it. The most likely fix would be that you should adjust the chainsaw chain’s tension. Adjust the chain’s tension after 15-20 minutes of use, but never try to adjust it when the chainsaw is running. Also, don’t try to fix it when it is hot. The chainsaw must be cooled down such that metal in the chainsaw chain contracts. This will give you a proper fit without actually bending the bar.

For tensioning the chain, loosen the two bar nuts located on the side of the chainsaw’s body. Hold the guide bar’s nose to lift it slightly, and then use a flathead screwdriver for turning the tensioning screw. The tensioning screw can be found in different places on different chainsaws. Sometimes, it is between the bar nuts, on the powerhead near the bar, or other sections of the clutch cover.

Release the guide bar and then tighten the bar nuts. You should check that the chain is tight enough by pinching it out of the bar groove. The chain needs to snap back into the groove once the chain is pinched. Use a screwdriver to push the chain along the guide bar and then check if it is moving freely. 

You can easily adjust the chainsaw chain and guide bar yourself. However, as it is a key component of the chainsaw, you can also consult a professional for expert help.

Chainsaw is cutting slowly

Another common issue that chainsaw users have is that the chainsaw sometimes cuts slowly. It is one of the most frustrating issues that can occur. If this is happening, you would have noticed that your chainsaw is producing a lot of sawdust. This isn’t an ideal situation. A chainsaw that is in top shape produces small wood chips when it is cutting and not sawdust. 

A slow-cutting chainsaw is an indication that you should sharpen the chainsaw or replace the chain. Consult a professional if you cannot manually find out the exact reason.

Chainsaw is making crooked cuts

If your chainsaw doesn’t make clean, straight cuts, sharpening may be an issue. A crooked cut could be a sign that you’ve sharpened your chainsaw incorrectly. Try to resharpen your chain properly. Make sure that you file all the cutters at the same angle. Remember to file the depth gauges at the same time.

If you’re having an issue sharpening the chainsaw, don’t hesitate in contacting a professional. It is better to consult a professional and be safe rather than do it yourself, make mistakes, and regret them later.

How to fix a chainsaw: Manually or with professional help

While most of the chainsaw issues are easily resolvable at home, never hesitate in contacting an expert. If you purchase a quality chainsaw, you can be assured that you’ll hardly face issues, but chainsaw issues are inevitable. Properly taking care of your chainsaw and following the proper protocols will help you avoid any drastic issues.

There may be small wear and tear issues. However, you can prevent them by keeping the more important parts in a proper condition. If you cannot get your chainsaw to function properly by yourself, your next step would be to contact a professional. A professional will be able to assess the chainsaw’s situation and use their expertise to easily fix the issue. If your chainsaw isn’t working properly, you shouldn’t write it off. More often than not, all it needs is some troubleshooting and it can go back to working smoothly and efficiently.

Repairing Chainsaws


Thank you for reading. Hopefully, now you have a better understanding of the common chainsaw problems and how to fix a chainsaw. Being aware of the common chainsaw problems will help prepare you for the inevitable. It will also make it easier and quicker for you to repair issues. In case you aren’t experienced and feel you cannot fix the issue yourself, always bring in a professional. A professional will fix the chainsaw before the issue escalates.

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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.