Part of the problem here is we don,t even know if it is a reedy. There are litterly hugh numbers of varients of the Cox .o49 that were indeed produced in the millions and they can work but you need to communicate. Post some good pictures of what you have.

After listening more I am inclined to agree with j.lunker and suspect a stuck reed which is very simple to clean but we really don,t even know if you have a reed. There were two types of reed the stamped brass reed in a star shape and a plastic one. The brass one did seem to stick quicker than the plastic type.

Ok if it does not have a built in tank there were some versions (though not in the same numbers) without but the majority of reed engines without tanks were called product engines. They were never sold as such individually but made up in many combinations of components for a specific product (airplane, car, boat, helicopter) with a separate tank.

Next question is, if it does not have a built in tank what arraingement for have you setup for a tank (fuel supply) and how far is it from the engine?