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Stihl Weed Whacker Low Power

What Causes Weed Whackers to Have Low Power?

If you have a weed wacker that has been losing power slowly over time, and you don't know what's causing it, there's a simple fix, which will take about ten minutes to perform. Located on the exhaust system is a screen covering the exhaust port, it's called a spark arrestor. The spark arrestor prevents flames from coming out of the exhaust system, which could cause a fire if the small engine was running and placed near any type of combustibles like dry sticks and leaves.

Back in the late 50's, the United States Forest Service wanted to prevent forest fires caused by logging equipment like chain saws, so they got together with the Society of Automotive Engineers and created the first spark arrestors. Today you can find spark arrestors on many small engines and equipment like weed wackers, chain saws, and lawnmowers.

Most spark arrestors are found on 2 stroke engines, the problem is that a 2 stroke engine will have a small amount of oil in its exhaust. This oil slowly gets trapped by the spark arrestor screen and eventually clogs the screen completely. Once the screen is clogged, the engine can no longer breath because the exhaust has no exit from the engine, it's the same idea as a clogged catalytic converter on an automobile. The engine will slowly lose power over time and it will also start to overheat because the exhaust is backing up into the engine.

Spark Arrestor Screen

Just remove the screw in the exhaust and slid the screen out with a pair of needle nose pliers. Clean the screen with carburetor cleaner and a wire brush, or just replace it with a new screen.

Just remove the screw in the exhaust and slid the screen out with a pair of needle nose pliers. Clean the screen with carburetor cleaner and a wire brush, or just replace it with a new screen.

How to Clean, Remove, or Replace the Spark Arrestor

Removing the spark arrestor is quite easy, but I recommend cleaning it or replacing it, not removing it all together. There is usually a small screw holding the spark arrestor in place, just remove the screw, and slide the screen out of its holder. Clean the screen with a wire wheel, wire brush, or simply soak it in some carburetor cleaner for about ten minutes, or you can replace it with a new one.

Once the spark arrestor is clean, your small engine will run like new again, the sound of the exhaust will be deeper, and all the power will be restored back into the machine, this simple fix will bring your tired old machine back to life for about the cost of a cup of coffee, and about the same amount of time it takes for the commercials to run while you're watching your favorite show.

Spread the word about this spark arrestor on Facebook, Pintrest, and Twitter, the same day I fixed my Stihl trimmer, a buddy of mine called me and asked me how to fix the same problem on his machine, which was an Echo trimmer, so I know a lot of people are having this problem, help share the information socially, you never know who will need it.

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Eddie Carrara (author) from New Hampshire on March 22, 2013:

Thanks Pinto, yes, I have learned quite a bit from reading hubs here, we all have something to contribute :)

Subhas from New Delhi, India on March 22, 2013:

Reading this hub, i realized that through hubpages we are gathering world of information which are very much applicable in our daily life; otherwise, we could have been looking for an answer under the open sky. Great hub with great info!

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