How to Put a Chain Back on an Electric Chainsaw


In the course of using a chainsaw, there will eventually come a time that you have to place the chain back along the bar. However, this can be a difficult and potentially dangerous task if you do not know what you are doing– something made all the more perilous if you are using an electric chainsaw.

Of course, the process is not as simple as just slapping a chain on your electric chainsaw, and then you are ready to go. That is why we came up with this guide to help demonstrate how to put a chain back on an electric chainsaw.

What You Will Need


  • Scrench (if included)
  • Socket wrench and flat head screwdriver if you do not have a scrench
  • Leather Gloves

Replacement or Realignment

  • Scrench (if included)
  • New chain (potentially)
  • Socket wrench and a flat head screwdriver if you do not have a scrench
  • Flat toothbrush
  • Leather Gloves



This is the first step you need to take if you are replacing the chain altogether which falls within the purview of putting a chain back on the electric chainsaw. When sizing the chain of your chainsaw, it is important to remember the 3 main specs used to fit chains: the pitch, the drive links, and the gauge.

Thankfully, not all of these specs diverge as much as the others with the overwhelming majority of chainsaw bars accepting chains that have a ⅜” pitch. The way that you determine the pitch is to take the distance between 3 separate links and divide it by 2 which might be tedious but it is important if you resharpen your chains to help keep track of them.

The drive links spec is literally how many total links there are on the chain which tends to be specific to a given chainsaw and is one of the more important parts preparations for the next section: safety. This is because putting a chain on a bar that is too long for it often leads to the chain sitting loose which can break and/or whip.

However, there are instances where different gauges and pitches can account for the difference in drive links– though the chainsaw’s manual will explicitly note it if possible. Speaking of gauge, this refers to how thick the tips of the bladed links are and impact how well the chain fits on the guide bar.

As such, the gauge can be the most deceptive spec of them all as the chain may seem to fit over the guide bar, but it is actually sitting looser than it should and poses a risk if used. This is also the only spec where the measurements are so minute and need to be so precise that you should take it to a shop to have a professional determine the gauge if you lose track.


To start with, make sure you have the proper safety equipment which generally only needs to be protective gloves, but depending on the disassembly, you might also want to wear protective eyewear.

After making sure you have the proper parts, what you need to do when putting a chain back on a chainsaw is to make sure that you do not have to worry about the chainsaw turning on while you interact with the chain. While many electric chainsaws come with a trigger lock to ensure that you do not accidentally turn the chainsaw on, this is not the most reliable way to stay safe.

For one, not every electric chainsaw comes with a trigger lock, but even then, it is possible for the trigger lock to fail, allowing you to accidentally turn the chainsaw on when you are not intending to. As such, the safest way to interact with the chain of an electric chainsaw is to remove its power source entirely, whether that means unplugging it from an outlet or removing the battery pack.

Despite what it may seem, some of the safety features are counter-productive for re-attaching or tightening the chain, specifically the chain brake. Some chainsaws use an inertia-activated chain brake while others connect the chain brake to the handguard, so the brake automatically engages if the chainsaw kicks back.

Because the chain brake prevents the clutch drive from moving altogether and you may need to remove the chain entirely, make sure to disengage the chain brake before trying to reattach or re-tension the chain. Whether your chainsaw has an inertia-activated or manual chain brake, you generally disengage the chain brake with the handguard lever.

Extra Features

One thing to consider, especially for electric chainsaws is that the tool may have an automatic chain tensioner. So long as you are not replacing the chain altogether, the automatic chain tensioner makes putting a chain back on the bar infinitely easier as you generally do not need to open up the chassis.

That said, even if your particular model comes with a chain tensioner, you need to make sure that the chain is still on the bar before trying to tension it to avoid potential damage or injury. If you do not feel comfortable with the chain’s stability, do not try and force the automatic chain tensioner and follow the continuing steps.


Screws and Cranks

Of course, if your electric chainsaw does not come with an automatic chain tensioning crank or the chain has come off of the bar’s track, you will need to use manual options. In terms of re-tensioning the chain, if the chainsaw does not have an automatic chain tensioning crank, you may want to check the tensioning screw first.

The chain tensioning screw sits below the guide bar’s retaining nuts and increases tension when turned clockwise while releasing tension when turned counterclockwise. However, the first step in this process is to loosen the guide bar’s retaining nuts, making sure not to take them completely off of the chassis.

Guide Bar

Once the guide bar is loosened, make sure to hold the guide bar’s nose upward while you tighten the chain’s tension. One thing to look for is how tight you end up tensioning the chain with too much tension preventing the chain from moving altogether.

A good way of gauging how much tension the chain has is by releasing the guide bar after tensioning the chain and lifting it back up. If the chain is too tight, the guide bar will feel resistance from the tension of the chain and either not move up all the way or strain against the chain.

If done properly, you should be able to move the chain along the guide bar by hand without the chain catching or binding anywhere along its path. From here, just make sure to remember to retighten the guide bar nuts, holding the guide bar’s nose upward as you do to prevent accidents.

Hot vs Cold

It is also important to remember that this process yields slightly different results whether you are tensioning a hot chain that has been used or a cold chain that has not. When finished, the chain should sit roughly 1/16” of an inch from the bottom of the guide bar if tensioning a hot chain, and you should unscrew the tensioning screw ¼ turn if the chain is too tight.

Keep in mind, if you tightened a hot chain, the chain started in a slightly looser arrangement and will eventually tighten back up when it cools off. Depending on how tight the cold chain gets, it could damage the chainsaw and will almost certainly do so over time if allowed to over-tighten multiple tensionings.

As such, any hot chain tightening needs to be loosened once you finish your cutting, following the same steps above except switching the tightening and loosening steps. Once the chain sits snug, but not too tight, against the guide bar, test out the chainsaw without cutting anything first to make sure the chain is properly set.



Sometimes, simply tensioning the chain is not enough, especially if the chain came completely off track from the guide bar or bunched inside of the chainsaw’s housing. In this instance, you will not be able to rely exclusively on the chain tensioning screw or automatic chain tensioning crank.

Thankfully, the process for reattaching a chain that has either come completely off of the guide bar, bunched within the housing, or broke starts the same way as manually tensioning the chain. First, you need to loosen the guide bar’s retaining nuts, this time removing them altogether– you should still hold up the nose of the guide bar while you do this to protect the tool.

Once the guide bar’s retaining nuts have been removed, next remove the guide bar’s side plate to reveal the interior of the chainsaw. Depending on the type of chainsaw you use, you may need to release the chain brake to remove the guide bar’s side panel and should do so if necessary.


Once you have the guide bar’s side plate separated from the housing, check to see if the chainsaw has debris anywhere inside of the housing. The area where the housing opens for the guide bar is the most likely spot for debris, but bits of sawdust, dirt, or plant material can get deeper into the housing.

This is where the toothbrush comes into play so you can remove any debris that got inside of the chainsaw’s housing. Not only will this make putting the chain back on the guide bar easier, regardless of whether it is a new or old chain, but it will also help keep the chainsaw in good working order.

The Chain

With the guide bar’s side plate removed, grab the guide bar’s nose and pull it away from the tensioner to release the chain’s tension. Once the chain’s tension releases from the guide bar it should lay slack, allowing you to easily remove it so long as it is not bunched– though that is uncommon and generally only occurs when running a chainsaw with far too loose of a chain.

If the chain does not come loose, you may be looking at an issue with either the chain brake or the guide bar’s rear sprocket, both of which will require removing the chain brake. Assuming the chain is not bunched or otherwise held immobile, remove the chain from the guide bar.

At this point, you should loosen the interior tension screw alongside the guide bar as this makes putting the chain back on the guide bar much easier. When threading the chain back onto the guide bar, make sure to start from the rear of the guide bar, wrapping around the clutch drum and making sure that the links thread along the rear sprocket.


One the chain is properly threaded along the guide bar, align the guide bar by pulling the nose forward away from the chainsaw and clutch drum to tension the chain a bit. As you align the guide bar, ensure that the bar sits on the chainsaw’s adjustment pin.

Once the bar is properly aligned, replace the guide bar’s side plate, retightening the guide bar’s retaining nuts, but do not tighten the retaining nuts. Instead, follow the appropriate steps in the previous section to properly tighten the chain along the guide bar as if you were only tightening it in the first place.

When you finish properly tightening the chain along the guide bar, tighten the guide bar’s retaining nuts on the side plate. From this point, you would be ready to go, but like with tightening the chain along the guide bar, it is better to be safe than sorry.

As such, try to start the chainsaw up and engage the throttle with no load (i.e. while not cutting anything). If the chain performs well, move on to a test cut on lighter material that is unlikely to test the tension.

Not only does this prevent any mistake from becoming worse, but it also heats the chain which may need to be re-tensioned once heated. If the heated chain needs re-tensioning, simply follow the steps in the previous section as before.


As we can see, putting a chain back on an electric chainsaw is not a terribly difficult task, but there is a specific set of procedures you need to follow to do so. On top of that, there are several minor tasks that do not technically involve putting the chain back on the electric chainsaw that you should still follow to improve the lifespan of the chain and tool– not to mention make the whole process easier.

Whether you simply need to tighten the chain so it sits snug on the guide bar or completely take the chain off and reattach it, this guide should help you avoid any trips to the repair shop. If the steps in this guide do not solve your issue, chances are something serious is wrong with the chainsaw and you need to take it to a repair shop.