RE: OS FSA 110 Problem
After two years, check some things: valve clearances, compression feel, fuel system cleanliness, carb blockages, leaking fuel lines, crud in the fuel tank, and so on. You may need to remove the engine from the model and check it carefully. Maybe you need to put it onto a test stand with a new, clean setup to check it out. Has anything changed? If you've had a major change in the weather, the carb will need to be reset.