i have an os 46fxi, and about 5 times in the last 2 days the prop falls off. the first time it did it the guy said it was a back fire that loosend the nut. but it keeps doing it. almost like my starter is just unscrewing it. ive been torquing the nut very hard and dont think thats an issue. i am getting worried cuz i dont want it to come off under full power. this cant be a common thing. anyone have any ideas on what my problem might be. or and ideas on what i can do to prevent future tragedies.