Why is my grass trimmer or brushcutter overheating? How to clean the cooling system
If your Husqvarna grass trimmer or brushcutter gets unusually hot, loses power during use or shuts off unexpectedly, the cooling system may be blocked.
Grass clippings, dust and debris can restrict airflow, preventing the engine from cooling properly. A blocked cooling system can cause overheating and may lead to engine damage if left unchecked.
Quick answer
If your grass trimmer or brushcutter is overheating:
- Check that the air intake is free from debris.
- Clean the cooling fins and surrounding areas.
- Make sure the cooling system is not blocked.
Regular cleaning helps maintain airflow and keeps the engine at the correct operating temperature.
Safety first:
Before cleaning the cooling system:
- Wear protective gloves.
- Turn off the engine.
- Disconnect the spark plug.
- Allow the engine to cool completely.
What you’ll need:
- Soft cleaning brush
- Clean cloth
Avoid washing the engine with water, as moisture can damage engine components.
Step-by-step: Clean the cooling system
Locate the cooling system
The cooling system includes:
- Air intake on a starter (1)
- Fins on a flywheel (2)
- Cooling fins on a cylinder (3)
- Cylinder cover (4)
- Muffler cover (5)
- Muffler plate (6)
Cooling system components on Husqvarna grass trimmer and brushcutter. Keep these areas clean to maintain proper airflow.
Remove dirt and debris
Using a soft brush:
- Remove the grass clippings
- Remove dust
- Remove leaves and other debris
Pay particular attention to the air intake openings and cooling fins.
Clean the cooling fins
Brush between the cooling fins until dirt has been removed.
Clean cooling fins allow heat to dissipate efficiently and help prevent overheating.
Check all airflow openings
Inspect:
- Starter air intake
- Cylinder cover
- Muffler cover
Make sure none of the openings are blocked.
Inspect before use
Before restoring the machine:
- Ensure all covers are correctly installed.
- Check that airflow openings remain clear.
Signs the cooling system needs cleaning
Clean the cooling system if your machine:
- Loses power while cutting
- Feels unusually hot
- Shuts off during long periods of use
- Has visible grass or dirt around the engine
These are common signs that airflow may be restricted.
Common mistakes to avoid
- Ignoring grass buildup around the engine
- Using water to clean engine components
- Operating the machine with blocked air vents
- Waiting until the engine overheats before cleaning
How often should you clean the cooling system?
Inspect the cooling system regularly.
Clean if:
- At least once a week during regular use.
- More frequently when working in dusty conditions or heavy vegetation.