That would not be to good!! I just enlarge the picture and it don't look like it had pulled through but I guess the head could have broke off .
I think I would pull the motor out and look though !! Good one NO17RW !
Oh my gosh, you guys are going to really screw this new guy up. vinnyvetere don't listen to them. If you fly without that one screw, it will all come apart and fly out of balance. The sky will fall. The fox will get in the hen house. The world will come to an... Oh, screw it. Hey Vinny,
If the plastic doesn't touch the motor, go fly. Find a replacement sometime and stick it in.
Life is good and it will hold together. Sometimes I just have to try to be funny.
Just make sure you don't drive a screw through the bottom of your motor. That's no joke.
I would not personally fly without them fitted. I have noticed that when I have forgotten to fit one of these in the past, the upper plastic arm can raise very slightly and impedes the motor rotation because the arm touches the motor housing slightly. Accepted that if you have left a screw off and the motor spins OK, it is unlikely to be a problem.
Although totally unrelated and not helpful to the OP and his, (or her) dilemma. Many years ago my brother in law was keen on stripping down his BSA Bantom motor bike on the pavement outside the house and he always seemed to end up with the odd few nuts and washers, he would start the bike up and if it run okay he would kick them down the road drain say, "they cant be that important if it runs well".