How to Replace a Grass Trimmer Metal Cutting Tool

Always switch the grass trimmer or brush cutter off before working on it. For petrol tools, remove the spark plug. For cordless tools, remove the battery or disconnect the connecting cable.

Ensure the correct deflector approved for your blade and model is fitted. Hold the trimmer upside down for better access to the gearbox.

Insert a lock pin or Allen key into the gearbox hole, then rotate the shaft until the lock pin clicks into place to secure it.

• Turn the nut clockwise to loosen it.
• Remove the blade and fastening parts but leave the thrust plate in place.
• Fit the new blade so the collar on the thrust plate fits perfectly into the bore.
• Add the thrust washer and rider plate to the shaft.
• Tighten the nut anti-clockwise using a combination socket tool.
• Replace any damaged or stripped nuts, then remove the locking tool from the shaft.

Switch the trimmer off and disconnect the power source. Check that the approved deflector is installed, then hold the trimmer with the spool facing upward.

• Insert a lock pin or Allen key into the gearbox and rotate until it clicks.
• Turn the trimmer head clockwise to remove it.
• Fit the new head by turning it anti-clockwise until it locks securely.
• Tighten while the shaft remains locked, then remove the pin.