Hi Rudy
The complete manual + exploded diagrams for the Hirobo HGE-20EH engine. This is the original gas engine supplied with the Hirobo Huey heli from the early 80's. I believe this was later replaced by a larger 25cc engine due to it being under powered. It has the light green fan cover.
If it sounds like the correct one let me know. Maybe with it you can figure out why my engine won't run properly