Shaun - I used to fly model airplanes & helicopters 70's until 1992. I am pretty sure your engines are late 80's early 90's 4 cycle, as they were a relatively new 'technology' in model airplane engines, for that time. 4 cycle were quieter, lower rpm, and could swing a larger prop for more realistic scale models.
Old model engine pricing seems to be volatile. Sometimes they bring big dollars, other times less. And I never seem to be selling at the right time.
