This article will cover the procedure of replacing the blade tensioner assembly.

If the bar is not tensioning properly (ie.) it does not grip properly and the tensioning screws do not tighten or loosen), then you may need to replace the whole 'tensioner assembly'. This is the side of your chainsaw, and includes the chain brake.

Note: The tensioning knob assembly is different for the Qualcast - Gardenline to the Spear & Jackson.

Rough instructions:

  1. Place the switch off to stop.
  2. Disengage the chain brake.
  3. Loosen knob and tensioner.
  4. Loosen so much as to take off the whole assembly, including the brake.
  5. To replace it, align the assembly with the bar and the tensioning screws.
  6. Tighten the tensioner so that it engages the screws.
  7. Tension the chain.
  8. Tighten the knob.