Why Does My Chainsaw Chain Keep Coming Off – Reasons And Fixes

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If you have a chainsaw that you regularly use, chances are that the chainsaw chain will eventually come off at some point. Not to worry, we are going to give you the answers you’re looking for. Go through this guide, and you will never have to ask yourself why does my chainsaw chain keep coming off.

Why does my chainsaw chain keep coming off?

If you own a chainsaw, it is highly likely that at some point your chainsaw chain will come off, causing a halt to your cutting or pruning tasks. There are several reasons your chainsaw can potentially come off. It might be due to wrong tension, drive sprocket being worn out, poor condition of the bar rail, and more. However, fixing the chainsaw is easier than you think. If you know the issue, you can easily fix it, instead of directly thinking that it’s the end of your chainsaw, and you have to buy a new one entirely.

man cutting trees using chainsaw

With that in mind, here are some of the reasons why your chainsaw chain keeps coming off.

Wrong chain tension

Many people are under the assumption that the more tension they add to their chainsaw chain, the better is the performance of the chainsaw. However, that cannot be farther from the truth. However, as it turns out, over-tightening the chainsaw isn’t the ideal route to take, neither is having less tension than what is needed. The catch here will be, if you notice that the chainsaw is too tight or too loose, you should check the chain tension.

With the right chain tension, the lifespan and productivity of the chain, motor, and chainsaw will increase. It is noteworthy that if the chain has too much tension, chances are that it’ll eventually come off. There are numerous ways to fix the tension, you can follow one of the methods and fix the tension of your chainsaw with ease and improve the performance of your chainsaw.

Drive sprocket may be worn out

You might have put back the chainsaw into position, but there is something that you might not notice, causing the chainsaw chain to come off. The drive sprocket might be the culprit due to the wear and tear that the propulsion on the chain. Over time, worn-out drives sprockets can fail to maintain an ideal tensile strength of the chain, let alone hold the chain in position. In such scenarios, you can expect the blade to occasionally throw the chainsaw chain off the groove if you frequently visit the yard for cutting trees or branches.

Bar heel might be worn out

Although most people can adjust the chain tension anytime it loses grip on the blade, it isn’t a long-term solution. The issue might be much more profound, needing the involvement of a professional chainsaw service/repairer. When you’re using a chainsaw, the chain can sometimes fall off if you have a worn-out bar heel. A bar heel is a component in the chainsaw located closest to the chainsaw’s drive sprocket.

If the bar heel wears out, it could potentially lengthen the distance a chain travels as the grooves become less effective. If the distance is increased, you can start expecting the chain to start to jump off the guiding bar.

Bar rails might be in poor condition

If your chainsaw chains keep coming out isn’t due to improper chain tension, bar heel, or worn-out drive sprocket, then it might be due to the bar rails being in poor condition. Say that of the components in your chainsaw, the bar rails are the ones that take a beating throughout the lifespan of the chainsaw, especially you frequently come out to cut woods. Among the other things that threaten the lifespan of the bar rail is working on full-throttle for an extended period of time, in which case the chain is at a very high speed. There is always a possibility of accidentally hitting a rock or metal in the log.

Damaged bar rails tend to cause more trouble for your powerful wood cutting machine. The most notable outcome here is that the drive links in the chain end up losing their smooth grip on the guiding bar. If you frequently use the chainsaw this way, chances are that it’ll come off the bar frequently.

Other possible reasons

While these are some of the most common reasons why your chainsaw chain keeps on coming out, there are a few other reasons as well. Some of those reasons include disengaged adjuster, loose guide bar, and improper application of chainsaw lubricant among others.

Tighten the chainsaw to prevent it from coming off

If you have a loose chainsaw chain that keeps coming off, a more important question eventually arises: how do you tighten the loose chain? The dime method is a great way of fixing a chain that is loose, and this method involves putting a dime between the chain and the guide bar when adjusting tension. There are a few other alternate ways of fixing loose chainsaw chains, which will help you keep proper tension on the chain.

When you start using a chainsaw for cutting or pruning your trees, the chain will inevitably stretch, ultimately becoming loose after a few uses. It becomes very difficult to cut wood if your chainsaw has a loose chain, while it also puts your safety at risk. To combat this issue, you should keep checking the tension of the chain frequently to determine if the tension in your chainsaw needs fixing or not.

Most importantly, you should take note that you cannot fix your chainsaw if you don’t know anything about the right tension. Lack of knowledge in this department of the machine will mean that you might not be able to fix the tension. Here is how you can fix the tension of the chainsaw chain –

Determine if the chainsaw has proper tension

You can easily determine if the chain is loose by pulling it off the chainsaw guide bar. A chain that easily comes off the bar will require tightening right away. Check the drive links and if they’re disengaged, then it’ll be the right time to adjust the tension of the chain.

Fix to get the right amount of tension in the chainsaw

If the drive links remain intact after pulling the chain, then everything is set, and you’re ready to cut or prune trees. In layman’s language, when you’re pulling the chain from the guide bar and there is a tiny gap in between, then your chainsaw has appropriate tension. However, make sure that the gap isn’t too big, as it would mean improper tension. Having tension in excess isn’t a good thing either, as chains that are too tight to move won’t cut the wood effectively even if your chainsaw is at full speed.

How to fix the chainsaw chain if it keeps coming off?

Having a chainsaw chain with proper tension will mean that you have to follow a few steps. If you do them correctly, it’ll only take you a few moments to get your chainsaw working at full-throttle once again. You should take note that when you’re setting the chain tension, you shouldn’t skip any steps as it would affect the way in which your chainsaw functions. For getting started, you’ll need a screw wrench. The good news for you is that most chainsaws tend to come with one. If you don’t have one, you can check at the local homesteading stores or online to get chainsaw screw wrenches.

fixing chainsaw chain
  1. The first step would be to loosen the chain and guide bar before you adjust them to the right tension. If the chainsaw brake is attached to the two components on the side panel, you can start off by unscrewing the brake before you remove the side panel.
  2. Now comes the time to adjust the tension screw located on the side of the guiding bars. When you are tightening it, the tension on the chain increases. In comparison, loosening the screw will release the tension on the chain, so it’ll become loose.
  3. The last step would be to tighten the guiding bar and nuts located on the side panel. Most importantly, you will have to lift the chainsaw nose at this stage for ensuring that the chain has a uniform tension all over the bar. Any object that is between the guide bar and the chain during this step will affect the chain tension of the chainsaw.
Chainsaw Troubleshooting: How to Keep The Chain From Coming Off The Bar | eReplacementParts.com


There you have it. Now you know all the reasons why your chainsaw chain keeps coming off, about the significance of tension in your chainsaw, and how you can fix the chainsaw chain within seconds. When it comes to fixing the chainsaw if the chain keeps coming off, you should remember to stay out of danger. While calling a professional for help might be the easy fix, especially if you’re not an expert with a chainsaw. But fixing a chainsaw that keeps coming off is easier than you think. Also, you should remember to keep all the safety precautions in mind when you’re working with a chainsaw chain or fixing it.

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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.