Rotor doesn’t unscrew

[Lovegmt73]

Hello
I have a problem with an Arf 116520 with gen rotor.
The rotor is loose, so I tried to tight the screw but it’s loose, cannot tighten or loose, someone can explain me how to solve this issue?
The screw turns freely and the watch winds but I wonder to fix this.
The bearing seems good

Inviato dal mio iPhone utilizzando Tapatalk

 

[ado213]

does the chrono centre seconds work in chrono mode ?. If not then you have pushed the rotor bush out of the bridge plate. if it does work in chrono mode then you have a stripped rotor bush thread,

Either way you will have to remove the bridge with the rotor attached to retrieve the situation

 

[Lovegmt73]

The chrono works, i removed the screw, it needs a new rotor bridge cause stripped bush thread, that’s all.