HavenĀ“t run into that one. However, the DT carb is pretty straight forward to work on. I would first try spraying some carb cleaner onto the linkage and the external mechanism and try working it up and down. This might work. If not, and if you are willing to take the carb apart, it is a pretty basic unit, easy to take apart. Use your digital camera and take pictures the whole way, to help you get it back together, and take the carb apart. Polish all moving parts to remove corrosion and oxidation, and you should be able to get things moving again. Good luck!