How do I replace the blade tension assembly on my Petrol Chainsaw

Modified on Fri, 12 Jun at 12:39 PM

This article explains how to replace the chain tensioner assembly if your chainsaw is no longer tensioning the chain correctly.

⚠️ Safety Notice

Ensure the chainsaw is switched off and placed in a safe position before carrying out any maintenance.

Wear suitable protective gloves when handling the chain and bar assembly.

When This Repair Is Needed

You may need to replace the tensioner assembly if:

The bar does not tighten or loosen correctly
The tensioning knob no longer engages properly
The chain cannot be adjusted despite correct operation
The side cover or chain brake housing is worn or damaged

The tensioner assembly is typically located on the side of the chainsaw and may include the chain brake mechanism.

Important Information

The tensioner assembly design may vary depending on the model.

Always refer to your specific model manual where available.

Replacement Procedure (General Guide)

Switch the chainsaw off and ensure it is fully stopped.
Disengage the chain brake.
Loosen the tensioning knob and bar cover fixings.
Remove the side cover assembly carefully, including the chain brake components where applicable.
Inspect the mounting area and ensure it is clean and free from debris.
Align the new tensioner assembly with the guide bar and tensioning screws.
Fit the assembly into position, ensuring the tensioning mechanism correctly engages.
Refit and secure the side cover.
Adjust the chain tension using the tensioning mechanism.
Tighten the knob securely once correct tension is achieved.

If the Issue Persists

If the replacement assembly does not resolve the issue, or you are unsure about installation, please contact our Technical Support Team for further assistance.

✔️ Summary

Switch chainsaw off and disengage chain brake
Remove side cover and old tensioner assembly
Align and fit new assembly correctly
Ensure tensioning mechanism engages properly
Re-tension chain and secure cover