My 1960 Farmall Cub fires up ok after replacing most of the replaceable parts over the past 12 months. But now there is a new problem: When the engine fires up the speed control lever does not change the engine speed and the engine runs full speed until I shut it all down. The speed control lever is very difficult to move with the engine running and even when I move it, the engine races full speed and I cannot turn it down. With the engine off, the speed control lever is easy to move. I am not a mechanic and only know what I've learned working on this Cub, but my guess is that the governor is the problem Any help would be very much appreciated. Thank you, Tom