Safety First
- Workspace: Find a clear surface or a stable workbench to prevent the chainsaw from tipping over.
- Protective Gear: Wear heavy-duty gloves made from robust material to protect yourself from injuries that might occur due to accidental activation of the chainsaw. Make sure to wear protective eyewear.
- Switching Off: If your chainsaw works on batteries, make sure to remove them. For electric chainsaws, disconnect the cords from the power source. For chainsaws that work on gas, switch off the engine and the spark plug. Pull the starter cord to be sure of this. Regardless, if you have used your chainsaw recently, allow it to cool down completely before you get to the replacement process.
- Chain Brakes: The chain brake is a mechanism that quickly stops the chain from rotating when activated. Even when the engine is off, applying the chain brakes is critical. This will prevent the chain from accidentally spinning during replacement. Consult your manual for specific instructions to do so.
- Chain Catcher: Make sure that your model has a chain catcher on the chainsaw body. While it prevents injuries by capturing a derailed or broken chain when in operation, there’s no har in having that extra layer of safety. Even while you replace the chain, if it were to accidentally slip or break during the process, the chain catcher will protect you.
How to Replace a Chainsaw Chain
Model Types
Whatever the type, to change your chainsaw chain, it will first have to be loosened from the tensioning mechanism, usually located on the side of the chainsaw. Follow this with the removal of the sprocket cover to access the sprocket that drives the chain. Based on the model of your chainsaw, there are two methods to do this -
- Type 1: Some models feature a wing nut that can be turned to loosen the sprocket cover and a thumb knob slightly above to either loosen or tighten the chain. These models allow you to tension and replace the chain without the need for additional tools.
- Type 2: Other models have a bar nut and tensioning screw instead that is located on the side of the chainsaw, which holds the sprocket cover in place.
The Process
- For Type 1: To loosen the sprocket cover, simply turn the wing nut counterclockwise. To loosen the tension on your chain, turn the thumb knob either left or right, depending on your model.
- For Type 2: To remove the sprocket cover, you will need to remove the nut. This requires you to have a scrench tool that usually would come along with your chainsaw. Use the screw end of the tool to loosen the tensioning screw. Now, loosen the nut bolt using the wrench side of the tool to remove the sprocket cover.
- In both cases, you will notice that as you turn the thumb knob or loosen the tensioning screw, the chain hangs loose from the guide bar.
- With the sprocket cover removed, the guide bar and the chain can be carefully dislodged from the chainsaw. Pull the guide bar back so that it releases from the sprocket gear. Then, you can pull your chain directly off the nose of the guide bar first, followed by removing the guide bar itself. Do this with care so that you don’t damage the sprocket or the chain.
This is a good time to brush off any sawdust that may have accumulated over or around the sprocket. Use a light-bristled brush. You can also use a flathead screwdriver to remove any dirt in the groove of the guide bar.
How to Put a New Chain
Knowing how to install the new chain on your chainsaw is an easy process that requires you to first secure the chain on the guide bar correctly and then secure the guide bar and sprocket cover back into place. Here’s how to go about these processes.
Replacing the Chain on the Guide Bar
- The sharp edges of the teeth on the chain need to be facing outwards. You can confirm this by comparing the chain with the diagram that is usually located on the guide bar.
- The inner side of the chain will have drive links that will interlock with the teeth of the sprocket, over which directional arrows will be etched. Make sure that these directional arrows point clockwise.
- To attach the chain to the guide bar, start by inserting the drive links of the chain into the grooves of the nose end of the guide bar first.
- After it has fitted well into the groove at the nose end, continue to insert the rest of the chain along the entire length and on both sides of the guide bar.
Fitting the Guide Bar
- Position the loop end of the chain onto the sprocket.
- Align the guide bar, ensuring the hole in the bar perfectly fits over the tensioning wheel (if it has a wing nut system) or stud (if it has tensioning screws over the sprocket cover) on your chainsaw body.
Tensioning the Chain and Securing the Sprocket Cover
- Replace the sprocket cover but don’t rush to tighten it just yet as the chain needs to be correctly tensioned first.
- For sprocket covers that have the wing nut, simply turn the wing nut clockwise for the cover to fit and then tension and tighten the chain by turning the thumb knob.
- For sprocket covers that have a screw that needs to be tightened, just as you used the screw end of the scrench earlier, tighten the screw so that the chain fits snugly against the underside of the guide bar. You can now tighten the nut bolt and secure the sprocket cover in place.
To check whether the chain is tensioned correctly or not, pull the chain underneath the guide bar. The chain should easily snap back into place. Also, check whether the chain can be pulled along the guide bar with the help of a screwdriver. This should happen with the chain brakes still disengaged.
- With your protective gear still on, engage the chain break and start the chainsaw to ensure that it works effectively and that everything is fitted snugly in place.