My Petrol Hedge Trimmer will not move the blade

Quick Answer

If the engine is running but the blades are not moving, the most common causes are debris trapped between the blades, inadequate lubrication, damaged blade teeth, or a fault within the gearbox or drive mechanism. Follow the checks below before contacting Technical Support.

⚠️ Safety Notice

Before carrying out any inspection:

• Switch off the hedge trimmer and allow the engine to cool completely.
• Remove the spark plug cap to prevent accidental starting.
• Wait until all moving parts have come to a complete stop.
• Always wear protective gloves when handling the cutting blades.

The blades are extremely sharp, even when the engine is not running.

Why Won't the Blades Move?

If the engine runs but the blades remain stationary, possible causes include:

• Debris trapped between the blades
• Poor blade lubrication
• Damaged or bent blade teeth
• Worn or damaged gearbox components
• A failed drive gear

Begin with the simple checks below before considering a mechanical repair.

Check Blade Lubrication

Regular lubrication helps the blades move freely and reduces wear on the gearbox.

Ensure the blades are lubricated using a suitable hedge trimmer blade lubricant or multi-purpose grease.

Poor lubrication can result in:

• Increased friction
• Reduced cutting performance
• Excessive strain on the drive mechanism
• Premature component wear

Check the Cutting Capacity

Attempting to cut material that exceeds the hedge trimmer's capacity can overload the drive system.

For the following models:

• QHTP26 – Maximum cutting diameter: 22 mm
• SLK26B – Maximum cutting diameter: 22 mm

For all other models, refer to your user manual for the recommended maximum branch diameter.

Check for Obstructions

Inspect the blades for anything preventing them from moving freely.

Look for:

• Twigs or branches trapped between the blade teeth
• Built-up sap or resin
• Dirt or other debris

Carefully remove any obstructions before restarting the hedge trimmer.

Inspect the Blade Teeth

Examine both blades for signs of damage, including:

• Bent teeth
• Broken teeth
• Excessive wear
• Misaligned blades

Damaged blades can prevent normal operation and should be replaced before further use.

Check the Gear Drive System

If the blades still do not move after completing the checks above, the fault may be within the gearbox.

Possible causes include:

• Worn drive gears
• Damaged gearbox components
• A failed drive gear (sometimes referred to as the bull gear)

These components transfer power from the engine to the cutting blades.

Important: Inspecting or repairing the gearbox requires partial disassembly of the hedge trimmer and should only be carried out by a suitably qualified person. Attempting this repair yourself may invalidate your warranty.

If the Problem Persists

If the engine runs normally but the blades still do not move:

• Do not continue operating the hedge trimmer.
• Do not dismantle the gearbox unless instructed by Technical Support.
• Contact our Technical Support Team for further assistance.

Our team can help diagnose the fault and advise whether replacement parts or a repair are required.

Frequently Asked Questions

Why is my hedge trimmer engine running but the blades are not moving?

The blades may be jammed by debris, damaged, poorly lubricated, or the gearbox may have developed a fault.

Can debris stop the blades from moving?

Yes. Small branches, sap, and other debris can become trapped between the blade teeth and prevent the blades from operating correctly.

How often should I lubricate the blades?

Lubricate the blades before and after use, and during extended periods of cutting to reduce friction and wear.

What is the drive gear (bull gear)?

The drive gear transfers power from the engine to the cutting blades. If it becomes worn or damaged, the engine may continue to run while the blades remain stationary.

Can I repair the gearbox myself?

No. Gearbox repairs require partial disassembly of the hedge trimmer and should only be carried out by a suitably qualified person, as unauthorised repairs may invalidate your warranty.