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Chainsaw Tool-Less Chain Tensioning. Tips from Professionals

A chainsaw requires proper chain tension to be able to cut efficiently. The chain should never be too loose or too tight, and its tension should be checked regularly. Chain tensioning on older chainsaw models is more tedious and requires some tools. However, this process has been eased up with the introduction of toolless chain tensioners. These allow adjustment of chain tension just by rotating an adjusting wheel without having to use any tool.

Chainsaw Tool-less Chain Tensioning:

Toolless chain tensioners have made chain tensioning quick and easy. A chainsaw chain can be tensioned with a tool-less tensioner in three easy steps:

  • Step 1: Disengage the chain by lifting out the flap and giving it a half counterclockwise turn.
  • Step 2: Adjust the chain tension by rotating the adjusting wheel until the proper tension is achieved.
  • Step 3: Re-engage the chain by giving the flap a 1/2 clockwise turn and folding it down.

The Proper Chain Tension:

If you are a new chainsaw user/ owner, you might ask, “What is the proper tension for my chainsaw chain?”

The proper tension on a chainsaw chain is not a quantified parameter. If you gather five professional chainsaw users, whether they are fallers, loggers, buckers, or pruners, ask them to tension up their chains as they see proper. You’ll get five different tensions, all of them fine.

The manufacturer’s recommended tension setting on a chainsaw chain is that when you look at the bottom of your guide bar, you see that the chain just snugly holds itself into the bar. The chain shouldn’t be hanging below the bottom side of the guide bar, nor should it be tucked too tightly into it.

Importance of Proper Chain Tension:

You don’t want the tension on your chain to be too less or too much, as a loose chain can’t do the job. Proper chain tension is critical for the cutter blades to apply the required force during operation. If the chain is too tight, the friction between the chain and the guide bar becomes too large for it to rotate at the required speed, requiring much more power to do the same job.

● Chain tension too tight

A chain that is too tight will also prematurely damage your chainsaw. This is because, during operation, the chain rotates at a high rpm of around 12,000. At such a high rotating speed, the large centrifugal forces try to convert it into a circle.

In doing so, the chain exerts all kinds of pushing and pulling forces on the bar. Especially on the tip of the bar and on the back of the sprocket. The tighter your chain tension, the more pressure it puts on the bar and the sprocket during operation. This can prematurely wear out the tip of the guide bar and the sprocket.

● Chain tension too loose

If the chain is too loose and sagging on the underside of the bar, it can easily come off the guide bar during operation. If the chain gets derailed during operation, it will damage itself, and the chain might whip around and hit something. This can potentially lead to serious injury.

For these reasons, maintaining the correct chain tension is extremely important.

What is a Tool-less Chain Tensioner and How to Use It:

Tensioning the chain on older model chainsaws requires at least a few basic tools, such as a screwdriver. Tensioning the chain is not hard if you have some experience and know what you need to do. The process takes a little time, including removing the drive or clutch cover to adjust the chain tension.

Some users complain that the repeated disassembly and assembly of the drive or clutch cover every time the chain becomes loose can wear out the nuts and bolts. Even though I have not experienced this, it can increase machine vibration due to mechanical looseness. Excessive vibration is detrimental to a machine’s health and must be avoided.

● Toolless chain tensioners make it easier

To increase the ease of adjusting the chain tension on a chainsaw for all users, chainsaw manufacturers have introduced toolless chain tensioners on their newer models.

With a toolless chain tensioner, the chain tension can be adjusted easily without removing the clutch or drive cover.

● New chainsaw or maintenance

Adjusting the chain tension on your chainsaw with a toolless tensioner can still be divided into two categories. The first category is tension adjustment of a new chain, either on a new chainsaw you have just purchased from the market or on your old chainsaw that needs a chain replacement.

The second category of tool-less tension adjustment is adjusting the tension of a chain that has become too loose after using it for some time.

Thus the first category of chain tensioning is a part of chain installation, and it needs to be done every time you install a new chain on your chainsaw. In contrast, the second category of tensioning is one of the most important parts of chainsaw maintenance.

● Tensioning a New Chain with a toolless tensioner:

Users must know how to properly install a chain on a new chainsaw or one that needs chain replacement to tension it up properly. Installing a new chain is not hard and generally does not need a mechanic. You can follow these easy steps to install and tension up a new chain on your chainsaw equipped with a toolless tensioner.

– Step 1: Remove the old chain

To install the chain on a new chainsaw, you must install the guide bar first. In any case, you’ll start by removing the clutch cover. First, lift out the flap until it clicks into position. Rotate the flap anticlockwise to loosen the clutch cover. Keep rotating until the flap comes off, thereby freeing the clutch cover.

Most flappers only require five to seven turns to come off. Remove the flapper and then remove the clutch cover. When removing the clutch cover for the first time, you must also remove the shipping spacer.

A shipping spacer is a rubber washer on one or two bar bolts to maintain proper space between bolts during shipment. After removing the shipping spacer, mount the bar on the bar bolts. Mount the bar on the designated bar bolts and gently push it back into its rear position.

– Step 2: Install the new chain

Once the bar is mounted (only for a new chainsaw), you can install the chain. I recommend taking care while installing the chain. The sharp edges of the cutters on your chain must be facing forward towards the bar’s tip.

Ensure that the cutter links fit into the clutch drum sprocket and run smoothly in the guide bar groove. Starting on the top side of the bar, feed the chain in the forward direction into the guide bar groove.

– Step 3: Tension the chain enough so it stays on

Pull the guide bar forward to tension the chain so it will stay on the bar. The clutch cover has a chain tension adjusting wheel. This wheel adjusts the position of the pin, which must be aligned with the pinhole in the bar.

Adjust the position of the pin so that it properly fits into the pinhole. If the pin does not insert in the pinhole, the adjusting wheel will not function.

– Step 4: Reassemble the clutch cover

Reassemble the clutch cover making sure that the pin inserts into the pinhole. Hand-tighten the chain by rotating the flap, but do not fold down the flap just yet.

– Step 5: Tighten the chain

Adjust the chain tension by turning the adjusting wheel clockwise. Keep tightening the chain until it does not sag on the bottom side of the guide bar.

– Step 6: Check if the chain can rotate easily

Hand-check that the chain moves easily around the guide bar. Tensioning the chain too tight will hinder the easy rotation of the chain around the guide bar.

– Step 7: Close the clutch cover

Lift the tip of the guide bar and lock it by closing the clutch cover. To do this, give the flap a couple of clockwise turns and then fold it down.

● Tensioning a Loose Chain with a toolless tensioner:

When you notice the chain on your chainsaw hanging loosely from the bar, it needs to tighten before you can use it. The toolless chain tensioners on newer model chainsaws have made this job quick and easy.

Locate the tension adjustment wheel, disengage the chain and rotate the adjustment wheel in the required direction. Let’s take the toolless chain tensioning on a Husqvarna E-series chainsaw as an example. The process can differ a little bit for other brands and models:

– Tool-less Chain Tensioning on a Husqvarna Chainsaw:

On a Husqvarna E-series chainsaw, the adjustment wheel (thumb wheel) is on the side of the chainsaw just below the flap on the clutch cover. Holding the bar up, pull out the flap handle and give it ½ turn in the counterclockwise direction to disengage the chain.

Use the thumb wheel to tighten the chain by spinning it downward. The chain is tensioned when the drive links cannot be visibly lifted from the guide bar groove. After the correct tension has been achieved, turn the flap handle back to its original position and fold it down to lock.

Fixing a Tool-Less Chain Tensioner:

A toolless tensioner lets users tension their chainsaws easily when they observe it is loose without needing other tools and a work table. Rotating a single wheel does the job for them.

However, after repeated use of the adjustment wheel, one might encounter the problem where rotating the adjustment wheel has no effect on the chain tension.

Fixing a toolless chain tensioner is possible, but you need to know how it works.

● How Does a Tool-less Tensioner Work:

The adjusting wheel of a toolless tensioner visible on the outside of your chainsaw right on the clutch cover is only a part of the whole tensioner assembly. This assembly includes a geared connector, a lead screw, a nylon or plastic bearing sleeve, and a pin/stem. These are located right behind the adjusting wheel on the inner side of the clutch cover.

The adjusting wheel connects to the geared connector attached to one end of the lead screw. The other end of the lead screw is in the bearing sleeve, which allows for its rotation. One end of the pin/stem is fixed on the lead screw while its other end inserts in the pinhole on the guide bar.

Rotating the adjusting wheel rotates the lead screw through the geared connector. As the screw rotates, the pin/stem moves in the pinhole. Depending on the direction of the pin’s movement, the chain is tightened or loosened.

Two plastic or metallic plates protect the tensioner assembly on the inner side of the clutch cover. One of these plates exerts pressure on the gear connecter to keep it connected to the adjusting wheel.

A toolless tensioner will fail to function if one of its parts breaks or wears out beyond an acceptable limit. If the plate exerting pressure on the geared connector becomes loose or breaks, it will also cause the tensioner to malfunction.

● Fixing The Tool-less Chain Tensioner that Won’t Work:

Generally, a toolless chain tensioner can be fixed by replacing wear out or broken parts and ensuring they are correctly connected.

If your toolless tensioner is malfunctioning, inspect its entire assembly. Move the parts with your hand to find parts with extensive wear or that are broken.

When you move the parts, try to find connections that have more slack than they should. When something is broken, it will be more obvious. Generally, parts of a toolless tensioner are available as spares and can be replaced.

Check the chainsaw tension every time before starting the job:

I recommend checking the chainsaw chain tension every time you use your saw. Proper tension is critical for your safety and the efficiency and life of your chainsaw. A loose chain can also come off the bar and cause injury.

Toolless chain tensioners make tensioning easy and quick. When a toolless tensioner starts malfunctioning after long use, you can repair it yourself or ask a professional for help.