Home » How to Tighten a Chainsaw Chain? (+ How Tight Should it Be)

How to Tighten a Chainsaw Chain? (+ How Tight Should it Be)

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The chainsaw is a reliable woodcutter that functions as its chain circulates the guide bar. It functions appropriately when the chain fits on the groove and does not come off no matter the speed.

However, constant use, extra pressure, and friction cause the chain to expand and loosen. A loose chainsaw chain is not only dangerous but leads to poor cuts. Heavy use can cause the chain of the chainsaw to loosen even faster.

When the chain lacks that snug fit on the guide bar, the person would be forced to exert more pressure when cutting wood. More pressure means the user expands more energy, and the cut loses precision.

Tightening loose chainsaw chains is easy, and anybody with little tool experience can handle it with the proper guidance.

Most brands share similar tightening processes, with a few featuring something different. However, users can tighten their loose chainsaw chains with the required information.

Why a Fit Chainsaw Chain is Essential?

Why a Fit Chainsaw Chain is Essential?

Getting a fit chainsaw chain is not a choice but a requirement for safety and clean cuts. To check if your chain is loose, observe the chains to see if any part leaves the guide bar when hanging freely and at rest.

A chain that fits too tightly to the guide bar is also a problem as it leaves no room for smooth rotation of the chain. You know the chain is too tight when it doesn’t move when you pull it. You can also check if it is too tight by grabbing a part of the chain and pulling it away from the guide bar.

How to Tighten Chainsaw Chain?

Tightening a loose chainsaw chain is simple and only requires a few tools.

Likewise, tensioning a chain is something anybody can do in minutes as long as they follow the correct process. Again, the only tool required is a chainsaw scrench, a flathead screwdriver, or a wrench.

1. Preparation


Safety is essential when working with power tools with sensitive parts like the chainsaw. Switch off the ignition and remove the spark plug wire to ensure there is no possibility of power entering the chainsaw.

The chain may be loose, but its teeth remain sharp and dangerous. Protect your hands by wearing thick safety gloves before touching the chain.

2. Check the Breaks

Check the Breaks

Some chainsaws have brakes on the side panel which may mean an extra step before you proceed to tighten. Unlock the brakes if it is attached to the side panel. Now you can work on the nuts without obstruction.

3. Loosen the Bar Nut

The bar nuts hold the guide bar to the side panel and keep the bar steady no matter the pressure. Locate the bar nut below the handle and loosen it with the end of a scrench.

When the bar nut is loose, it allows the guide bar to move up and down. It’ll also allow the bar to move forward, giving room to adjust the chain.

4. Locate and Adjust the Tensioning Screw

Locate and Adjust the Tensioning Screw

The Tensioning screw controls the tension in the chain and can be tightened and loosened as required.

Here, tighten the bolt to increase the chain’s tension and shorten it. This tensioning screw is located at the side of the guide bar. Typically, the screw will be close to the panel and have a flat head.

You can use a flathead screwdriver to tighten the chain. Check the correct turning position of the screw by turning it slightly in both directions.

Adjusting the tensioning screw draws loose chain parts inside the side panel chamber. This action feels like the screw reduces the size of the chain when you tighten it.

5. Check the Tension

Check the Tension

Grab and pull the chain away from the guide bar to see if it is tight enough. You can move to the next step if you’ve got the desired tightness.

Also Read: How to Clean Your Electric Chainsaw?

6. Re-Adjust the Guide Bar Nut

Re-Adjust the Guide Bar Nut

After getting your desired tightness, the next step is to readjust the guide bar nut, which loosened earlier.

First, slightly raise the tip of the guide bar to avoid locking it in the wrong position. Next, use the socket end of the scrench to tighten the nut till the bar is firmly secured and does not move anymore.

7. Test the Chainsaw

Test the Chainsaw

Testing is important to be sure you have the right tightness and guide bar position.

First, please turn on the guide bar by getting it to the power source and attaching the spark plug wire. Next, use the chainsaw to cut a small piece of wood. Observe strange sounds and vibrations showing a loose nut or part.

Tighten any loose nuts and enjoy the chainsaw.

How Tight Should a Chainsaw Chain be?

Many people do not know how tight a chainsaw chain should be, and sometimes go ahead to over tighten the chain. The correct tightness for a chainsaw chain is when it fits snugly on the guide bar.

Grab the chain and pull it away from the guide bar. It should show a little stretch, but no chain part should leave the guide bar. This position shows the chain is tight enough.

Why Does the Chain Keep Coming Loose?

Tightening a chainsaw chain is easy; however, doing this every time is not a fun activity. If your chainsaw chain keeps coming loose, it may show a different problem altogether. Here are some reasons chainsaw chains lose frequently:

1. Unstable Temperature

When the temperature changes from cool to hot, it leads to slight changes in the chain length. Hot temperature forces metal to expand, while cool temperature forces it to contract.

The temperature of the chain gets hot when working for long, which can make the metal expand, thereby making it lose.

2. Bad Chain or Guide Bar

If the guide bar or chain is bad, the chain may keep coming loose. If the edge of the guide bar where the chain rests is damaged, the chain will struggle to stay tight.

The same can be said when the chain rail keeping it on the guide bar gets damaged.

3. Wrong Chain Positioning

When the chain is not properly set on the guide bar, it can lead to frequent loosening.

The chain has a rail that should fit on the guide bar groove. When this position is altered, the chain may keep loose no matter how tight you tighten it.


Here are some common questions about tightening chainsaw chains and their answers:

How to know when a chainsaw chain is loose?

You can test by pulling the chain and checking if any part of it is out of the guide bar grooves. You can also know that your chainsaw is loose when you have to exert a lot of pressure before cutting.

How often should you tighten the chain?

It depends on how often you use the chainsaw. For example, a four-hour continuous work may require you to tighten the chain up to three times.

Why does the chainsaw smoke?

A smoking chainsaw may result from the extra pressure on the guide bar to cut. A loose chain saw may cause you to exert a lot of pressure on the bar and‌ make the chain smoke.


Depending on the type of chainsaw, some have knobs instead of screws for tightening loose chainsaw chains. For chainsaws with screws, the process may be more than turning a knob, but it is still simple.