How To Adjust The Chain Slack On Your Chainsaw

Many a tree-loving homeowner might tell you that having a good chainsaw tucked away in your garage or tool shed can be incredibly useful when it's time to clear fallen limbs. A chainsaw will also come in handy if you're merely looking to keep a clean profile among the trees adorning your property.  

As beneficial as a gas or electric chainsaw can be when you've got tree branches that need cutting, the device won't be as effective if it hasn't been properly maintained, and there are several measures you can take to ensure your chainsaw is cutting cleanly and effectively. Those measures include oiling the bar and chain, sharpening its teeth, and ensuring the chain is debris-free after each use. There is another, less obvious step you can take to help ensure your chainsaw is functioning at maximum cutting capacity. It's called "tensioning," and it involves adjusting how much slack there is in your saw's chain.

If you're curious how your chain may have loosened, the heavy vibration and friction involved in cutting wood are typically enough to cause such an issue over time. Likewise, new chainsaws may loosen slightly after their initial use. As for why you need to keep the chain tight, too much slack can increase the chances of kickback or a chain being thrown off the guide bar entirely. Here's what you need to do to adjust the slack on your chainsaw.       

How to tighten your chainsaw chain

If you're wondering how to determine if your chainsaw chain is too loose, a tell-tale sign is the need to exert extra pressure on the saw to make a clean cut. Thankfully, most modern chainsaws make it easy for users to tighten the chain, though you will need a flathead screwdriver and a socket wrench (or a combination of both, called a scrench) to make adjustments. With those tools on hand, you can follow these steps to adjust the chain's slack.

  1. Locate the chain-tensioning adjustment pin on your chainsaw. On many models, this will be located on the side of the device near the bolts that hold the bar in place. It should have a slot for a flathead screwdriver.
  2. Use the socket wrench to loosen the bolts holding the bar in place without removing them. There may be as many as three.
  3. Insert your screwdriver into the pin and, turning it clockwise, tighten the chain onto the bar. 
  4. Test the chain's slack by pulling down with your thumb and forefinger. If the entire chain can be pulled below the bar, continue tightening until only a small space can be seen between the chain and the bar.
  5. When you reach the desired tightness, retighten the bolts on your saw.

The steps of tightening a chainsaw chain may vary depending on its make and model. If you're confused at any step in the process, consult your User's Manual for guidance or take your chainsaw to a professional for service, as any misstep could lead to personal injury or machine failure.