Thank you for your question.
I am sorry you are having a problem with the trimmer. If the fuel mixture in the trimmer is older than 5 weeks old, it should be drained. Then refill with fresh fuel mix. If this does not help I suspect there is a problem with the fuel system. I recommend checking in the fuel tank first. When you look in the tank, you should see a fuel line with a white filter attached to the end. Then inspect the fuel line. If it is hard and brittle, it has to be replaced.
is a video that shows how to replace the fuel line. If the fuel line is fine, I suspect the carburetor is to blame. The carburetor will have to be cleaned or replaced.
is a video that show how to clean the carburetor. Before you remove the carburetor, make sure to note the fuel line and cable connections. This will save a lot of frustration later. The parts for the trimmer can be ordered from the following link.
Parts for Craftsman trimmer
If everything mentioned above is ok, you can check the muffler. The muffler has a screen inside of it that can plug up. When it plugs up the engine cannot breathe and may not speed up. To clean the screen you have to remove the muffler. Then use carburetor cleaner and a wire brush to clean the screen. Once it is clean, reassemble the unit, and check the operation.
I hope this helpful. If you need further assistance, please reply below with more details.
If you do not feel confident repairing this problem yourself, then you can have it repaired by a Sears technician. Here is a link that will provide the nearest drop-off locations:
Sears Home Services
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