my FUXTEC 4T brushcutter has now just about 4 BSTD. unfortunately on strike and after prolonged operation. After working about 1 hour. They are on the mind and requires half an hour. Break so they can cool off. When inquiring at FUXTEC was told that this is not a warranty item, I should adjust the carburetor (goes to the device not at all) and a new spark plug screw (after 4 Hours.). So much for customer service FUXTEC. But beautiful she looks the trimmer, but that's it. The screws should not be too often loosen and tighten, because the hold then never.