i'm creating a quadcopter for a schoolproject, and i was trying to combine a motor and a piston, so it could fly away while spinning its rotors. I've read a post somewhere and they explaned it good to me, but when I tried to do it the same way (by making a group of the motor and a random block) the rotor was just acting weird and wasn't doing anything logic. Is there any way to fix it? I added the file so you can see what's happening.

Any Ideas what i'm doing wrong????

I tried it at one rotor, I don't understand why it doesn't work...