Kiev 4 upper curtain drum locked

[zorroflores]

I kindly request the help of the experts on the Kiev 4.

I was cleaning the shutter module assembly, separate from the rest of the camera, looking into some uneven firing. At some point I rolled by hand the upper curtain drum beyond the point where is normally cocked and as a result the drum is now locked.

I tried to free it by moving the gear train that goes between the winding knob and the drum but somehow, somewhere there is a blockage, can anyone suggest where to look for or indicate a method to free it?

May be I should try to disassemble the drum and free the blockage form there on. I suspect that I managed to unsynchronize the drum from the winding knob cocked position.

Thanks in advance for your help