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3 Reasons Chainsaw Chains Don’t Tighten (With Fixes)

The chainsaw is a pretty powerful but vaguely dangerous piece of technology. It can easily cut off a chunk of large trees and damage anything if not taken care of properly. One of the major problems that chainsaw users frequently complain about is the chain coming off from its place. There are several reasons for chainsaw chains becoming loose.

The main reasons chainsaw chains don’t tighten are:

  • Chain Setting: Incorrect setting between the bar and the chain can make it difficult for the chain to tighten.
  • Temperature Variation: Temperatures changes can affect the chain dimensions causing it to loosen or tighten.
  • Mechanical Problem: Mechanical defects can affect the chain’s placement on the bar.

The first law of safety regarding chainsaws includes checking the build of the chain and its base thoroughly. The chain can become loose over time because of rough usage. A chainsaw chain needs to be checked both before and after using the machine. Without proper maintenance, the results of a loose chainsaw can be severe. Using the chainsaw repeatedly without tightening it properly can permanently damage the chain and even the chainsaw base.

As a mechanic and machine enthusiast, I’ve come across several occasions where I had to face difficulties due to the fitting of the chain. If you’re facing a similar problem, the first thing to know is the different types of chain fittings and how they work.

The chainsaw is not a complex piece of machinery when it comes to the basics. It’s actually a combination of some gears and sprockets. The motor is attached to the endpoint of the chainsaw, and it provides the necessary power required to drive the chain. The chain is attached to the base, and it runs the speed from the motor to the outer base. The proper alignment of the chain is a must to get the highest results from a chainsaw. The chain tension is an essential thing to check every time before using the device, as the chain can come off at any time if it’s not aligned properly. You can guess the damage that can occur at times like that.


Tight the chain before using the chainsaw

To properly work with a chainsaw, you need to tighten the chain each time before using the machine. But, how can you know when to tighten the chain and when to loosen it up? To know that, you need some general knowledge of different chain positions and conditions. Mostly, there are three conditions that your chain can be in. Here are three tightening conditions of chainsaw chains!

1. Under Tightened

To know the correct tension of the chain, simply give it a pull upwards and see how well it is attached to the base. If the chain seems to feel loose and comes off without you putting any effort, it is surely under tightened. An under-tightened chain will be sluggish during operation. On top of that, the chain can come off at any time during the job, and it can cause severe damage to the operator and surrounding.

An under-tightened chain will not function properly, and the performance will decrease in every way possible. When a chainsaw chain becomes under tightened, it loses the proper grip and, as a result, can’t cut the way it’s supposed to. This causes a decrease in performance and reliability. Sometimes, if the chain is loose, it can come off while the machine is on. Just imagine something as dangerous as that flying towards you or your house. The result won’t be pretty, and chances are, it will be more devastating than the effects of a wrecking ball.

2. Over Tightened

If pulling the chain does not show any effect and the chain seems to be tightly attached to the bar, the chain is over tightened and that is also not good. Over-tightened chains can’t perform correctly as they are too close to the bar. This can cause negative effects on the handlebar and controlling the chainsaw will become more difficult.

Over tightened chains sometimes get stuck. The condition becomes more out of control if the machine runs at high speed. The chainsaw can stop abruptly in the middle of the operation and can even get stuck at a certain point. This can cause severe damage to the mechanical parts of the chainsaw and even cause an explosion out of the blue.

3. Properly Attached

What’s the proper position for the chain? If you give it a pull and find a tiny space between the chain and the base, the chain is properly attached to the bar. The space between the chain and the bar is vital as it will determine the efficiency of the chainsaw. A properly attached chain will make the chainsaw perform better and lag less.

A properly attached chain will function the way it’s supposed to, and you won’t have to retighten it every time. There must be a simple gap between the two surfaces to perform correctly. The gap should be less than half an inch.

Chainsaw Issue
Reason Involved
The basic settings of the connection between the bar and the chain might be damaged or malfunctioned due to invalid dimensions
To change and reset the basic settings, in-depth knowledge of the structure is needed. The proper alignment is necessary, along with the placement of the bar and sprocket.
As chainsaws function through a powerful motor, the temperature rises with respect to time and it plays an important role in changing the dimensions of the chain
To get rid of the heating problem, the chainsaw must be stored at a dry place with room temperature and the device should not be used over and over again without stopping for it to cool down
The complex structure of the chainsaw can come with defects from the manufacturer or get damaged due to over-usage
If the parts are damaged slightly, they can be replaced, but if there is permanent or manufacturer defect involved, it’s better to seek professional help

3 Reasons Chainsaw Chains Don’t Tighten

Now that we’re clear on the chain positions, it’s time to know which conditions lead the chain to become loose over time. These reasons apply to most of the chainsaw types out there in the market. Here are the reasons behind the loosening of chainsaw chains!

1. Chain Setting

The setting of the chain denotes the initial position of the chain when it was manufactured. If your chainsaw chain wasn’t properly attached to the exact position, no matter how much you try to set it to the right position, it won’t work. The setting denotes the exact position at which the chain should be on the bar. The required tension of the chain depends on the position.

When your chainsaw chain becomes loose, you need to set the chain to this exact setting in order to get the best results. Some of the chainsaws in the market have automatic adjusting levers that adjust the chain to the perfect setting after each time it’s used. There are two bolts attached to the sidebar panel that further strengthens the attachment. The bolt defines the strength of the attachment. If the bolt is misplaced or not perfectly tightened, the chain won’t be in its place for too long.

If your chainsaw had a setting error, the chain will abruptly get out of position and loosen up over time. This can happen because of a manufacturer error, rough usage, and other causes. Whatever the reason is, the only way to fix your chainsaw at this stage is to reset the settings and make sure the chain is properly aligned with the side panel. Different types of chainsaws come with different chain settings. Some are loosely fit on purpose while others require tight fits. To know if your chainsaw has a problem with its chain setting, look through the manual and find the basic information on the chain material. Steel alloys are reliable because they don’t get damaged by corrosion. Your chain setting may get damaged because of the material too. So check the material type before determining the problem associated with the chain.

2. Temperature Variation

The chainsaw is a potent piece of technology with a high-performing motor attached to the end. The motor runs at a very high speed, and the chain runs with the power it gets from it. With high velocity, a certain rise in temperature is inevitable. I’ve seen older chainsaw models which would rise to 50 degrees in just a couple of seconds.

The variation of temperature creates a challenging situation for the chain. As the length of metallic substances increases along with the temperature rise, the same goes for chainsaw chains too. When you use your chainsaw for an extended period of time, you will easily notice the change. The chain length abruptly increases to a larger size because of temperature variation. As the size increases, the chain becomes loose.

On the other hand, if the chainsaw is stored at a rather cold place, the chain will gradually tighten more as metallic materials tend to contract when they’re stored at a cold place. That means, for the temperature variation, you would need to fix the position of the chain after and before every use. This can be very troublesome if you live in a very hot or cold country. The surrounding temperature plays a vital role in deciding the quality of the metallic chain. The chain tension will rise or fall abruptly whenever the chainsaw is used.

3. Mechanical Problem

Besides the setting error and temperature issues, there’s a bigger problem surrounding the chainsaw chain, and it’s related to the mechanical side. To understand this problem properly, you need to know the basic outline of the processes in your chainsaw and what happens when you tighten or loosen the chainsaw chain.

The chain tension is calculated by the distance available between the bar and the sprocket. The internal structure of the chainsaw contains a bar attached at one end to the sprocket with the chain attached to the whole bar. When you rotate the nut in the clockwise direction, the bar’s distance and the sprocket become greater. That means the bar gets further away from the sprocket, and as a result, the chain attaches itself tightly to the bar.

If your chainsaw chain becomes loose without even using it, there might be an issue with the proper settings. If the internal structure of the chainsaw malfunctions, the chain won’t stay in its place for long. If the internal structure is somehow damaged or causing defects, tightening the chain over and over again won’t work. If you’re facing this problem, you should take your chainsaw to a local shop. You can do many types of maintenances all by yourself but can’t fix the mechanical issues.

How To Tighten Chainsaw Chain

As you already know the different positions of chains in the chainsaw, troubleshooting it will not be so difficult. But the most important thing to keep in mind is knowing your limits. You can’t tighten the chain too much or too little. The proportion of pressure should be at a certain level that suits the exact type of your chainsaw. To know the proper pressure value, look through the manual that was provided with your chainsaw.

The steps involved are pretty easy but you need to follow them with caution. There will be a few screw openings and position shifting processes and each of these should be placed at its proper position. Even the slightest mistake can cause a lot of damage to your property and even to yourself.

To start with the process, we need some tools first. There’s a pretty widespread and popular tool called Scwrench that’s supplied with the chainsaw. It’s a general combination of a screwdriver and a wrench. This tool is pretty easy to find and works like magic in the case of chainsaw troubleshooting. Here are the steps to follow to tighten your chainsaw chain!

– Step 1: Loosening The Nuts

To begin the troubleshooting, you need first to loosen up the nuts situated at the sidebar. The sidebar works as a support for the chain and guide bar. Loosening it up will provide easier access. Use a Husqvarna scwrench to remove the nut from the sidebar easily. Don’t forget to keep the nut in a safe place while you’re working, as these tiny things tend to get lost. Do this with caution as the nut is loosely connected to the base, and putting too much pressure can damage the base along with the nut. I don’t think there’s anyone who would try to remove the nut while the machine is on, so always take safety precautions before attempting to troubleshoot the chainsaw.

Step 2: Rotating The Side Bar Nut

This is the main step of the tightening process. Remember, this step will include manually rotating the sidebar nut to tighten the chain. The pressure you need to tighten the chain properly must be decided by you only. To begin, look at the sidebar and locate the nut attached to the panel. Now, take the scwrench and rotate the nut in a clockwise direction. Each rotation will end up tightening the chain little by little. To know if your work is done, pull the chain upwards and try to feel the tension between the chain and the bar. If the chain feels properly attached, your work here is done. Pull the chain up over and over again if the pressure seems less. Rotate the nut in a counterclockwise direction if the chain feels over-tightened.

Step 3: Final Touch

Just like you did in the first step, attach the nut you extracted from the sidebar and make sure it’s properly attached to it. After that, pull the chain again and see if it’s tightened as expected. Give the chainsaw a go and see if the chain is working perfectly or not. If there’s any problem with the chain, repeat the steps from the top. When the connection between the chain and the base is perfect, it will work like magic. Due to the reasons I mentioned earlier, the chain can easily lose tension on its own even after a single-use. To make sure the chain stays in its place, you can try buying an automated chain-fixing chainsaw. These chainsaws are more reliable and need less maintenance than traditional ones.

Final Thoughts

The chainsaw is a wonderful piece of technology with great power. If properly used, it can cut through almost anything. And, if it’s not handled with care, the damage can be severe. The chain of a chainsaw needs to be at the proper alignment to function perfectly. As I’ve mentioned all the necessary details to find out the problems with the chain and how you can resolve them, it won’t be so easy if you don’t remember the basics. Remember, you need to know the basic functions of machinery to troubleshoot it properly. So, get the hang of the basic structure and working principle from the aforementioned notes and work properly. Have a nice time ahead!

• Chain Tensioner Screw

A pivotal component of the mechanism that tightens chain-drives is the chain tensioner screw. When this screw becomes stripped, it dramatically reduces its effectiveness in performing its role, originating serious malfunctions.

The tensioner screw secures the chain in place while it operates. If in any case, it comes loose or is stripped, the chain will not tighten properly. This is a common problem and it often arises due to over-tightening or cross-threading.

From my experience, maintaining the chain tensioner screw in the right condition can avert many chain tightening issues. A periodic check of the screw to ensure that it is not stripped is highly advisable.

Details about stripping processes can be accessed from the University of Cambridge Materials Science Department website.

• Heat Induced Chain Stretch

Industrially, chains are subjected to conditions of high heat which can lead to excessive stretching over time. The heat causes the metal to expand, increasing the length of the chain.

The stretching of a chain can undermine the functionality of the chain tensioner, ultimately leading to a failure in its operations. The tensioner works on specific dimensions and any slight alteration to the chain length can disrupt the equilibrium.

From my professional standpoint, avoiding exposing chain-drives to high heat or installing heat-resistant chains can help mitigate this problem.

• Chain Size Mismatch

In the assembly of chain-drives, using the wrong chain size can result in an improper tightening. The chain tensioner screw dimensions are designed to accommodate a specific chain size, and mismatched combinations can lead to unfavorable outcomes.

The importance of using the required chain size cannot thereby be underemphasized. Always consult the equipments manual or an experienced technician to confirm the correct chain dimensions.

• Worn-out Chain Sprockets

Chain sprockets, over time, tend to wear out due to the continuous rotation and friction from the chain. This causes irregularities in the sprocket tooth profile which makes it difficult for the chain to sit properly and tighten.

Through my professional journey, I have found that routine maintenance and periodic replacement of worn-out sprockets alleviate the malfunctions attributed to this issue.

The National Institute for Occupational Safety and Health (NIOSH) has useful resources for maintaining the integrity of mechanical components.

• Chain Brake Engagement

In some instances, the chain brake may be engaged which prevents the chain from tightening. The chain brake is a safety feature that stops the chain when a sudden movement or kickback occurs.

However, if the chain brake is inadvertently left engaged, the chain will not tighten as it should. It is paramount to always ensure that the chain brake is disengaged before attempting to tighten the chain.

Through experience, I can indeed affirm that double-checking the chain brake status averts unnecessary chain tightening glitches.

The Alliance for Green Heats safety protocol for chain-drives is an excellent additional resource.

Main Reasons for Chainsaw Chains Becoming Loose: Improper Chain Setting

The foremost issue leading to chainsaw chains becoming loose is incorrect chain setting. Based on my experience, a proper adjustment is essential to maintain the stability of your tool. A loose chain can make your chainsaw less effective and at the same time, hazardous.

• The Impact of Temperature On Chainsaw Chains’ Tightness

If you notice, you may find your chainsaw chain often getting loose during high temperature. The reason for this is straightforward – chainsaw chains are made of metal. These metals have a tendency to expand as the temperature goes up.

When the saw heats up during use, the metal expands, causing the chain to loosen. Therefore, it is ideal to allow the chainsaw to rest at regular intervals during use. And remember, always handle it with care and caution when it’s heated up.

• Guide Bar and Chain Condition: Another Major Contributing Factor

The overall condition of the guide bar and chain plays a crucial role in maintaining the chains’ tightness. It’s important to ensure that the chain and guide bar are clean and free from debris.

Moreover, the guide bar should not be worn out. The combination of a dirty chain, debris-caked guide bar, and worn-down bars can significantly contribute to chain looseness.

• Internal Mechanism Failure: How It Affects Chainsaw Chain Tension

Sometimes, the chainsaw’s interior mechanism’s failure or damage can influence the tensioning system. Issues such as malfunctioned bearings, gear problems, or obstructed oiling systems can cause the chainsaw chain to come loose. Regular service and maintenance can help in minimizing these issues.

• The Risk of Over-tightening the Chain

Everyone wants their chainsaw to be on-point and function without any glitches. But many people tend to over-tighten the chainsaw chain in this process.

This common mistake leads to numerous problems, including premature chain and bar wear. The appropriate chain tension can be determined using a pull test. Remember, an overly tightened chain is not a solution; it can cause more harm.

• Using a Scwrench: A Handy Tool

A special tool known as a scwrench, which is a combination of a screwdriver and wrench, can be a game-changer for tightening a chainsaw chain. It’s easy to use and can make your chainsaw maintenance task significantly more straightforward.

• Further Actions: Understanding Basic Chainsaw Mechanics

Like any other tool, a chainsaw requires an understanding of its basic mechanics for efficient troubleshooting and maintenance. Gaining knowledge about chainsaw parts and their operations can go a long way in managing your tool better.

I recommend SAF Chainsaw & Crosscut Saw Training Course from Southern Appalachian Wilderness Stewards to learn more about chainsaw mechanics.

In conclusion, chainsaw chain maintenance is a combination of appropriate chain setting, adapting to temperature changes, proper cleaning, dealing with internal mechanism issues, avoiding over-tightening, and having a scwrench handy. Once you grasp these, your chainsaw is sure to serve you better, for longer.

How to Check and Adjust Your Chainsaw Chain Tension

Tending to your chainsaw’s chain is crucial for peak performance and safety. Ignoring this aspect can lead to premature wear and tear or, worse, dangerous recoil during operation. The first step is checking the tension.

• Testing Chainsaw Chain Tension

Checking the tension of the chainsaw chain is simple. Hold the chain in the middle of the top of the guide bar. Give it a sharp, quick snap. If the chain is well-adjusted, it will spring back into place smoothly.

A properly adjusted chain can be easily moved around the guide bar but offers minor resistance. The chain’s resistance should signify an ideal level of tension, not so tight as to restrict movement, but not loose enough to let the chain dismount the bar.

• Understanding Proper Chainsaw Chain Movement

It’s essential to note the correct functioning when the chainsaw is in idle mode. There should be no movement of the chain when the engine idles.

Links of a well-adjusted chain will always stick to the guide bar, even when lifted away from it. This lack of movement during the idle state ensures an optimum level of tension that keeps the chainsaw operation safe and effective.

• Chainsaw Chain Adjustment Process

If the chain pressure isn’t ideal, you’ll need to adjust the chain. The initial step is to loosen the nuts holding the guide bar in place. These would typically be located on the chainsaw’s side panel. Make sure your chainsaw is turned off and has cooled down before you start this adjustment process.

• Using the Tension Control Screw

The tension control screw plays a crucial role in adjusting your chainsaw tension. Turning this screw to the right will tighten the chain; conversely, turning it to the left will loosen it. This makes for an easy and quick way to adjust the chain tension according to the task at hand.

• Issues with the Tension Adjustment Screw

Remember, the tension adjustment screw and the chainsaw case threads holding the screw should be in good condition. If either is stripped, the chain will not tighten adequately.

Regular inspection of these parts will ensure your chainsaw retains an efficient operational mode. For stripped screws, consider seeking professional advice or referring to a reliable source for part replacement, like Oregon Products.

• Importance of the Correct Guide Bar Size

If you’ve recently replaced your guide bar, ensure it is of the correct size. The wrong-sized guide bar can cause tension issues with your chainsaw chain, affecting both safety and performance.

• Dealing with a Persistently Loose Chain

Occasionally, even after maximum tightening, the chain may still feel loose. If so, it might be necessary to remove one or more links from the chain. But remember, this should be the last resort after trying all other tension adjustment steps.

• How to Remove Chainsaw Chain Links

Most chainsaw chains have a master link that allows for easy removal of chain links. The process usually needs a flat-head screwdriver to open the master link and remove unnecessary links. Always remember to refer back to your manufacturer’s guide for precise instructions.

• Prioritizing Safety in Chainsaw Operations

Safety cannot be overemphasized when dealing with a chainsaw. Always adhere to safety precautions right from the start of the chainsaw setup to its usage.

Always wear appropriate protective gear, ensure your chainsaw is in good working condition, and maintain a clear, clutter-free environment when operating a chainsaw.

So, by understanding the essentials of chainsaw chain tension, regular check-ups, and adjustments, you can ensure your chainsaw performs optimally and safely. Always remember that regular maintenance is key, not just for chainsaw longevity, but for your safety as well.

Analyzing the Problem: Stihl Chainsaw Tension Screw Issue

From the scenario, it’s clear this individual is facing a problem with their Stihl chainsaw’s tension screw. This problem, if prolonged, may affect the overall efficiency of the chainsaw.

• Proposed Solution: Manually Tightening the Chain

The issue can potentially be addressed by manually tightening the chain. One of our posters has suggested this as a solution.

It’s relatively straightforward: Pull on the bar and use the adjusting screw to further tighten the chain until it is snug. This method has proven effective for many and might be the immediate fix required.

• Another Possibility: Worn Drive Sprocket

Nonetheless, if the above intervention doesn’t work, it could mean the drive sprocket might be worn. This situation could render the chain appearing longer than it is. This link provides detailed insight into chainsaw maintenance and an understanding of the role of different components.

I would recommend trying a different chain or considering replacing the drive sprocket as potential resolution. Sometimes, the best solution might be the simplest one, and changing a worn-out part can restore normal functionality.

• Shedding Light on Chain Issues: Older Chains Might Be Worn, Too Long

According to another poster, the problem might not be the drive sprocket. It’s possible the chain itself is worn and has become too long. Chainsaws are machines that face a lot of wear and tear. Over time, the chains could start showing signs of this strain.

• Breaking Down the Solution: Addressing Worn Sprocket

One of the posters has confirmed that the sprocket was slightly worn in their chainsaw, and replacing the chain with a new one resolved the tightening issue. No further steps were required to address the problem. This might reinforce our hypothesis about chains extending over time due to wear and tear.

• Understanding Chain Mechanics: Chains Can Stretch with Time

We must understand chains can stretch or wear over time. This can potentially make the initial chain longer. One of our regular posters underlines this point. They mention a possible method – removing a link from the chain, but they discourage this.

Removing a link could potentially solve the issue in the short term, but it might cause other complications later on down the line. It would be beneficial to rule out this option unless it’s the last resort.

• A Final Note: Expert Recommendations

From our discussions, it’s clear that chainsaw issues – be they due to the tension screw or the chain itself – can be resolved effectively. Remember, the immediate solution might lie in manually tightening the chain or dealing with problematic components such as a worn-out sprocket or a stretched chain.

Remember to approach the problem systematically and consider all possibilities before zeroing in on a solution. As ever, safety is of utmost importance when dealing with mechanical issues, so ensure you’re well-protected before performing any troubleshooting exercises on your chainsaw.