Nikon FM infinite Advance problem.
I recently acquired a very clean FM (early 3 knurled knob version). It’s in good shape but it has the infinite advance issue. That is to say, I can wind the advance lever multiple times in a row without firing the shutter. this should not be the case as there is supposed to be a locking mechanism which prevents the advance lever from being actuated when the shutter is charged.
I have restored an FE before and I am familiar with the film advance locking mechanism on that camera. Thinking the FM would be the same, I opened up the bottom cover and inspected the mechanism. However, after looking at the mechanism for a long time, I don’t think that the advance locking mechanism is on the bottom of the camera at all.
I flipped the camera up and took the top off. I disassembled it past the film counter and down to some gears but I could not find the component that was supposed to lock the advance lever.
does anyone out there know how the advance lever lock is supposed to work on a Nikon FM? I‘m wondering if it might be deep inside the camera perhaps necessitating separating the body and the mirror box. hopefully that’s not the case. I’d appreciate any help. Thanks!