8 Common problems with Chainsaws & How to fix them

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While you’re bound to be troubled if any of your power tools start to malfunction, but when your chainsaw starts acting up, it should immediately be a cause of concern for you.

On one hand, a chainsaw is a pretty expensive power tool, and not taking the proper troubleshooting steps could mean the difference between a working saw and a ruined one.

On the other hand, a chainsaw is a very dangerous tool, and not addressing the issue can lead to you fatally injuring yourself the next time you use it. Clearly, any apprehension you feel is justified.

Fortunately for you, most of the problems you’d face with your chainsaw are easily fixable, should you properly follow some simple troubleshooting steps. Sure, the process can be involved with some of the trickier problems, but as long as you closely follow the instructions, even a novice can take care of a troublesome chainsaw.

Common problems with Chainsaws

Here are some of the more common problems faced by chainsaw owners, and how you can go about solving each one:

1 – Chainsaw won’t start (Gas & Electric Chainsaws)

If you’re having trouble turning your electric chainsaw on, it might well just be a simple power issue. First check the power button; I know, I know, the button was probably the first thing you checked before searching for clues on the internet, but still, look again. Many a professional have made the silly error of not properly switching it on, so it’s not too much of a stretch to think you might have made a blunder too.

If the switch isn’t the culprit, then there’s probably an issue with the power cord and/or extension cord you’re using. Check the connections again, from your chainsaw power cord to the extension cord and then to the mains power supply, to see if they’re all properly connected. Try plugging in your chainsaw directly into the mains without the extension, to see if you can rule the extension out as faulty.

If your gas chainsaw won’t start, check the on switch again, and try turning the choke before you kickstart the chainsaw with the ripcord again. If the chainsaw starts with the choke on, immediately turn the choke off and give the motor a couple of powerful revs by squeezing the trigger. This will warm up the engine and get the oil and fuel into the combustion chamber, after which it should be good to go.

If using the choke doesn’t work, try draining the fuel tank and refilling it with fresh oil and gas, in the right ratio. Old fuel can sometimes clog up your engine, preventing it from starting up properly. If replacing the fuel still doesn’t work, then the fault may lie with your spark plug. Remove it and clean any soot off it you see before replacing it, or just chuck it into the bin after replacing it with a new one.

If none of the above suggestions fix your problem, then the fault most likely lies with the chainsaw itself. Best to just show it to a professional chainsaw repairman, instead of taking it apart yourself and making matters worse in the process.

2 – Engine idles roughly or stalls (Gas Chainsaws Only)

It’s not advisable to use a gas chainsaw whose engine idles roughly or stalls in between use. In the former case, continuing to use it may damage the chainsaw in the long run, while in the latter case, you’d have to stop and restart your chainsaw again and again while working.

Fortunately for you, this is mostly an issue with how the carburetor’s been tuned, and fixing it is no complicated process. We won’t get into it here with how you can re-adjust your carburetor (mostly because a textual description would be tedious to read and hard to follow), but you can follow along with this helpful tutorial:

If re-adjusting the carburetor doesn’t do the trick, then it might just be broken and you’ll either have to get it repaired or replaced by a professional.

3 – Chainsaw lacks power in each cut (Electric & Gas Chainsaws)

During cutting, you may suddenly feel like your chainsaw lacks the power it had previously, since each cut now takes longer than it should. While this may point to a problem with your motor, in which case you’d need to get it checked by a professional, it’s also very possible that the issue is something that you can easily resolve yourself.

If you feel like your electric chainsaw is lacking in power, it may be because the electric supply to it may be dwindling in voltage. If you’re using a battery-powered chainsaw, it could simply mean you need to recharge your saw before working again, but with a corded saw it’s possible that your mains power supply is facing a reduction in voltage. 

If you have a gas chainsaw instead, you may need to check the air filter, which may have gotten dirty and clogged after long periods of use. Simply remove it and clean it, or replace it with a new one, and check if the problem goes away. It might also help to drain the fuel tank and add fresh oil and gas in the right ratios, and you could also try re-adjusting the carburetor to see if that does the trick.

Another cause for a lack of power on both electric and gas chainsaws is the chain brake not being properly disengaged. Obviously, if your chain brake was properly engaged, then the chain wouldn’t spin and you’d know what the problem was immediately.

However, if the chain brake is only slightly engaged (which can happen as your chainsaw gets older), then it may be causing a reduction in power, with the chain not spinning with every rev of the engine. So, you should check by pulling the brake back as far as you can to completely disengage it.

4 – The engine is smoking (Gas chainsaws only)

Your engine smoking during use is never a good sign, since it points to inefficient combustion of the fuel, which could damage your chainsaw in the long run. To stop it from smoking, your goal is to therefore ensure the combustion process inside the chainsaw is as efficient as possible.

Most likely, you forgot to switch the choke off properly after starting the chainsaw, and the engine is smoking as a result of not getting enough oxygen for combustion. If the choke is not the cause of the problem, then things like cleaning the air filter, adjusting the carburetor, and draining and refilling the oil and gas usually do the trick when it comes to a smoky engine.

Note: A smoky engine is not the same issue as a getting a burning smell from your chainsaw motor. In the latter case, you should immediately stop using the chainsaw and get it checked by a professional as soon as possible. Failing to do so could permanently damage your chainsaw motor, rendering it completely useless in the future.

5 – Chain doesn’t move (Electric & Gas Chainsaws)

If the chain on your chainsaw doesn’t spin despite you being able to rev the motor using the trigger, it’s very possible your chain brake is to blame. The chain brake keeps the chain from spinning with the motor when engaged, and so is very useful in case of accidents to stop the operator from hurting itself. Simply pull the chain brake lever back towards the handle to disengage it, after which the chain should start spinning.

If the chain brake was not the cause of the problem, then it might just be that you’ve put your chain on too loose or too tight on the guard bar. In either case, the chain wouldn’t properly spin around the bar, so you need to tighten or loosen it accordingly.

The ideal tension adjustment for all chainsaws is to tighten the chainsaw so much that it fits snugly on the bar, while simultaneously being loose enough to allow you to pull off one or two links when you pull on the chain from the bottom. However, the chain should snap back into place when you release the pulled links making a “SNAP” sound. This is why it’s called the “Snap Test” for checking chain tension.

It’s also possible the fault lies with the adjustment of the carburetor. Follow the steps detailed in the video above, and you’ll be able to properly tune the carburetor to get your chainsaw running in no time.

6 – The chain makes a clattering sound as it moves along the bar (Electric & Gas Chainsaws)

The fault in this case almost always lies with the tensioning of the chain, which is probably set too loose on the guide bar. Simply tighten the chain with the tensioning tool, that comes with each chainsaw out of the box, though some chainsaws come with a built-in tool too. Tighten it enough so you can successfully perform the “Snap Test” (detailed in the previous section), after which your chain shouldn’t clatter anymore.

If the problem persists, then your chainsaw may be broken in one or two places. Try replacing the chain with a new one to see if that solves the issue, and discard the old chain immediately if so. Using a chainsaw with a weak, faulty chain is only asking for trouble; there’s no knowing when it could snap mid-use and injure you in the process.

If the chain is not what’s causing the problem, then you might need to inspect your guide bar. The bar can get pretty worn out with repeated use, so it’s important to check its condition every once in a while.

In this case, the culprit may be a burr on the chain’s path of travel that’s causing the clattering. File down any burrs you find with a flat mill bastard file. However, if the bar is just too worn out or bent or broken in any place, it’s best to just replace it with a new one.

7 – The chainsaw doesn’t cut as smoothly or as quickly as before (Electric & Gas Chainsaws)

If you feel like your chainsaw doesn’t cut as smoothly or as quickly as it used to in the past, then it’s highly likely you’re using a chain that’s gone blunt over use. A blunt chain cuts much, much slower than a sharp chain, and you’re only ever going to get messy cuts with it.

Sharpening your chainsaw chain by hand is an inherently simple process, but it requires the right tools and proper technique to get the job done right. This is why we recommend most people to get their chainsaws sharpened by a professional, instead of trying to do it themselves.

However, that doesn’t mean you can’t do it yourself if you really want to. It might not be as perfect a job as a repairman would do it, but it can certainly be good enough provided you perform every step as well as you can. Here’s helpful video to show you how to sharpen a chainsaw yourself.

Sharpening your chainsaw is something you’ll have to do time and time again; the more you use your chainsaw, the faster the chain dulls and needs to be resharpened. However, if sharpening the chain by hand isn’t something that’s super appealing, you can look into invest in chainsaws with an automatic chain sharpening kit. These chainsaws sharpen the chain with a built-in sharpening stone, making the whole process as simple as just pushing down a lever and pulling the trigger.

Do note, however, that it’s not a good idea to sharpen the same chain over and over again multiple times. Chains age as they are used, and somewhere down the line you’ll eventually have to replace the chain for a new one.

Using a worn-out chain also isn’t a good idea for the risks it poses. After all, it could break mid-use and fly off the bar, injuring you in the process. Best to change it before it’s too late.

8 – Your chainsaw is leaking gas (Gas chainsaws only)

The first thing you should do if you spot your chainsaw leaking gas is to IMMEDIATELY switch it off and step away from it. If you’ve been using the chainsaw for a while before you noticed the problem, wait until the chainsaw cools down before doing anything; a leaking gas chainsaw is a big fire hazard and should be treated as such.

After the chainsaw has cooled down, safely drain the tank, allowing ample time for all the fuel to evaporate off the chainsaw tank and body before proceeding. Be sure to move to a well-ventilated area before doing so, and check the fuel lines on your chainsaw.

Fuel lines are thin pipes connected to the carburetor that carry fuel to and from the tank during internal combustion. These pipes can get brittle over time and crack, resulting in fuel leaking. If your fuel lines have indeed broken, you can easily replace them with new ones, though be careful about the size and the way they’re originally inserted into the chainsaw.

It’s also possible that the leak has originated from your carburetor or the fuel tank itself, both of which could have gotten damaged and started to leak. Replacing these parts is much trickier than fuel lines, so we’d advise you to leave this task to a professional repairman.

In either case, you simply can’t continue using your gas chainsaw if it’s leaking fuel, so put it aside until you’ve gotten it repaired.

About Albert P Emmanuel

Hi, It’s the Albert Powell Emmanuel here. You can call me APE. I am the founder of ChainsawAPE. Here, on this website, I aim to teach you all you need to know about chainsaws – yeah, those sharp, scary things that intimidate you. Well, they’re not that hard to use.

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