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Weed Eater Dies When It Gets Hot – 7 Common Causes

A weed eater is made of three main parts:

  1. A string line within a rotating head
  2. An engine powered by petrol, electricity, or a battery
  3. A long connecting shaft with a handle

The heat created in the process is typically funneled away into the atmosphere.

Weed eater dies when it gets hot causes, how to fix it

If the heat is not emitted correctly or the engine is overworked, the weed eater can overheat and stop functioning.

While most overheating problems are associated with the engine, the string head can also burn out.

If you are experiencing overheating problems with your trimmer, the following checklist will assist you in identifying the issue and solving it.

Overheating In Engines

Clogged Cooling System

Most weed eaters have cooling fins within the engine cylinders. The fins help remove hot air from the engine.

They can be clogged by vegetation and other debris during operation, preventing the engine from cooling properly.


The cooling fins can be cleaned using an old toothbrush. To gain access to them, several covers may need to be removed. Your user manual will have details on how to open the covers.

Dirty Air Passages In Petrol Engines

The air passages are made up of the air filter and the muffler. The air filter takes clean and cold air to the engine that is used in combustion.

The muffler assists in removing heated gases from the engine.

If either of these units is blocked, air circulation will be disrupted, and the engine will overheat.


To clear out the air passages, the pads of the air filter can be removed and washed. The muffler can be cleaned with a wire brush.

Fuel-related Issues In Petrol Engines

For 2-stroke engines, petrol and oil must be mixed using the correct ratios.

If the mixture is done incorrectly and there is too much petrol, the fuel will burn at a higher temperature.

This will cause the engine to overheat.


Follow the measurement and mixing instructions provided in the owner’s manual.

The fuel and oil must be premixed before pouring into the tank so that they blend evenly.

The mixture can only be used for up to 30 days before it goes bad.

The Carburettor Needs An Adjustment (Petrol Engines)

All petrol weed whackers require their carburetor to be adjusted at some point.

In the carburetor, petrol and air mix before ignition by the spark plug.

If the carburetor feeds too much fuel into the engine, the engine will overheat.


Every carburetor comes with adaptable screws that are used to control the amount of fuel fed into the engine.

The instruction manual of your weed eater will detail how to access the carburetor and adjust it.

Incorrect Power Supply For Corded Weed Eaters

Electrical trimmers experience less mechanical issues than petrol ones, but they are also less powerful.

Overheating in them is often caused by using a voltage supply that is too high.

For example, a 210-volt supply will cause overheating and damage a 110-volt machine.


Read your owner’s manual to check what voltage is used by your weed eater. Then use an outdoor extension cable that has the correct capacity.

Using Battery Weed Eaters For Large Workloads

Battery-powered weed eaters are not as powerful as petrol ones. They can be overworked and overheat if they are used to clear thick and overgrown garden areas.


Thickets should be cleared using a powerful petrol trimmer or other gardening tools. Battery-powered weed eaters should only be used for clearing grass and weeds.

Overheating In The String Head

A Build-up Of Debris Around The String Head

If weeds, other debris, or extra string line wrap around the shaft, it causes friction and overheating around the string head.

Additionally, using a string with a diameter too big for your weed eater can damage its engine.


With the motor off, check if the spool in the string head is easy to move and free of debris.

The spool can also be removed to check the movement of the shaft.

Additionally, when trimming long grass, the weed eater must not be pushed too far into the vegetation to prevent overworking and tangling the machine.

Never Work With A Machine That Is Too Hot

Overheating can damage a weed eater beyond repair.

Parts of the string head can melt and fuse, rendering it useless.

Additionally, the engine can smoke and burn out spark plugs, plus other units, so that the machine never works again.

Overheating also makes weed eater’s fire hazards, especially around dry and flammable vegetation.