My Thunder Tiger .61 will run backwards, quite well. No, the plane will not run backwards. If started backwards, it will ussually spit on idle, but will spool all the way up, and will even have power to take off and fly.

Don't ask me how i discovered this. Most of you old timers can probably figure it out. Don't make me explain, i have served my pennance.

Since you dis-assembled the thing, who knows? this engine definitely is meant to run counterclockwise as viewed from the prop shaft.

yes, a regular prop when spun backwards still screws.... mine is 11 x 7.5

i dont have the answers, just the experiences.

Steve-o