Skip to Content

What to do about a leaf blower losing power?

As fall approaches, people start bringing their leaf blowers out to rid their lawns of fallen leaves. To work efficiently, a leaf blower should be at its optimal power because it requires a decent amount of airflow from the leaf blower nozzle to blow away leaves and other debris. Insufficient power can make the job inefficient and tedious.

What to do about a leaf blower losing power?

If your leaf blower starts and idles but loses power when you rev it then you can do the following things to troubleshoot this problem:

  • Check the muffler and the spark arrestor
  • Inspect the carburetor
  • Examine the sparkplug  
  • Check the air filter
  • Examine the battery (For electric leaf blowers)

There can be multiple reasons for a leaf blower losing power. A good way to fix this problem is to check all of the above-mentioned components of your leaf blower to get rid of the issue and get optimal power from your machine. While it is easy to check and fix most of the items in this checklist, some may require professional help, and in this article, we will explain what to do if your leaf blower is losing power while running.

● Check the Muffler and the Spark Arrestor

Not to be confused with the sparkplug that is fitted on the cylinder head of the engine, the spark arrestor is a device used in the exhaust muffler and it prevents sparks or other flammable debris from escaping through the exhaust muffler. It is a very useful device because if a spark escapes from a leaf blower it can cause the dry leaves to catch fire, not to mention that a leaf blower would be unbearably loud if the spark arrestor is not installed in it. But sometimes the spark arrestor can get clogged and it will prevent exhaust gases from getting out of the muffler causing the leaf blower to bog down and lose power when it is revved. You can check the spark arrestor of your leaf blower using the steps explained below:

– Step 1: Locate the spark arrestor:

Locate the exhaust of your leaf blower and at the tip of the exhaust, you will find the spark arrestor.


If your leaf blower has a muffler cover or a muffler tip, you will have to remove it before you can access the spark arrestor.

– Step 2: Remove the Spark Arrestor:

In order to remove the spark arrestor, you might have to use different methods depending on the type of leaf blower you have. For some models, you can remove the spark arrestor screen directly from the muffler tip by using a 15mm socket while in others, you will have to remove it using a screwdriver.

– Step 3: Clean the Arrestor Screen:

With the spark arrestor removed, check the screen and if you can’t see through the screen you will have to clean it up. But if the screen isn’t black and you can see through it, the spark arrestor isn’t clogged.

You can use a hard brush to clean up the screen of the spark arrestor but the proper way to do it is to burn off the debris stuck in the spark arrestor screen using a blow torch. If your leaf blower’s spark arrestor is clogged to the point where it can’t be cleaned, you can always get a new one and install it on your leaf blower muffler to fix the issue of low power.

Here you can find a new leaf blower spark arrestor.

● Inspect the Carburetor of your Leaf Blower

If gas has been sitting inside your leaf blower’s carburetor or you have been putting dirty fuel in your leaf blower, it can cause the carburetor to get clogged, and it won’t be able to supply proper air-fuel mixture resulting in the leaf blower engine losing power. Or the carburetor might have an improper mixture setting causing it to lose power at higher RPM.

– Checking the Air-Fuel Mixture of the Carburetor  

To check if the carburetor’s air-fuel mixture is causing loss of power, you will have to adjust the mixture screw on the carburetor by turning it clockwise or anti-clockwise, half turn at a time until the leaf blower starts producing optimal power. Make sure not to make sudden adjustments and turn these screws for a minimal rotation while revving the engine to see if the adjustments had any effect on the leaf blower’s power.

– Checking if the Carburetor is Dirty

If you want to check whether your leaf blower’s carburetor is clogged you will have to disassemble the carburetor completely. If you find any debris in the jets of the carburetor, clean the carburetor using a carb cleaner and reinstall the carburetor to check if the leaf blower is producing proper power.  

While you are checking the carburetor of your leaf blower you should also check the fuel lines to see whether they have a blockage or not. If the fuel lines are blocked they can restrict the fuel supply to the carburetor and the engine, causing low power.

Here you can find a new carburetor for you leaf blower.

● Examining the Sparkplug of your Leaf Blower

Leaf blowers, just like any other equipment with a combustion engine, require a sparkplug to produce combustion inside the cylinder of their engines. Since most leaf blowers have a 2 stroke motor, it is not uncommon for the sparkplug to go bad quickly because 2 stroke engines have a reputation for requiring frequent spark plug replacements. A bad or worn sparkplug will not produce the proper spark that is required to make an optimal amount of power. So a bad sparkplug is one of the more common causes of poor performance from a leaf blower. You can check the spark plug of your leaf blower by following these simple steps:

– Step 1: Remove the Spark Plug Wire:

Disconnect the sparkplug boot to access the spark plug underneath it.

– Step 2: Remove the Plug:

Take the correct sized socket, seat it on the sparkplug and turn the sparkplug anti-clockwise to remove it from the cylinder.

– Step 3: Examine the Electrodes:

With the sparkplug removed, pay close attention to the firing tip of the sparkplug’s center electrode, specifically to the insulator tip around the firing tip. If this insulator tip is coated with carbon or engine oil, then it is a sign that the sparkplug has gone bad and needs replacement. Other than the fouled insulator nose, you should also check whether there is any damage to the electrodes or not. If the electrodes of the sparkplug are damaged, or there is a coating on the insulating tip, then replacing the sparkplug might fix the low power output of your leaf blower.

Here you can find a new sparkplug for your leaf blower.

● Checking the Air Filter of your Leaf Blower

Leaf blower engines require clean filtered air to produce a powerful flow of air. This is why leaf blower engines are fitted with air filters to supply clean air to the engine. But oftentimes, the air filters can become clogged with debris that starves the engine of air, and your leaf blower stops producing optimal power. To check and replace the air filter, you need to perform the following steps:

– Step 1: Remove the Air Filter Cover:

Locate the air filter cover and remove it by either turning a knob or removing a screw.

– Step 2: Replace the Filter:

When the cover is removed you will find the air filter under it. If you notice that the air filter is clogged with debris or it is damaged or punctured replace it with a new one.

If your leaf blower has a foam filter, you can also clean the air filter if it is not cracked or damaged by washing it under warm water, and you can even use soap. But make sure the air filter is completely dry before reinstalling it. With a clean air filter in place, your leaf blower’s engine will be able to breathe in clean air and make the right amount of power.

Here you can find a new air filter for your leaf blower.

● Check the Battery of your Leaf Blower

If you have an electric cordless leaf blower and it doesn’t work even when the battery is fully charged, it indicates a problem with the battery of your leaf blower. Unfortunately, you cannot replace a leaf blower battery, and the only way to fix this issue is by installing a new battery. Make sure to get the correct type of replacement battery with the correct voltage and amp ratings.

Here you can find a new battery for your cordless electric leaf blower.

Final Remarks

Normally a leaf blower loses power after it has been stored for a long time or if it has not been maintained properly. If you keep an eye on the above-mentioned components and properly maintain your leaf blower you can expect it to produce maximum power for seasons to come. With some basic tools and care, you can fix the poor performance of your leaf blower at home. So before you throw away your leaf blower or go buy a new one, inspect the components of your leaf blower using the methods explained in this article, and chances are, you will be able to make the leaf blower work at maximum power.