I've been using these for over 30 years, first on an Fm2n and now also with an FM3a, I have three.
Originally Posted by brianentz
They are great when they work, fast and all that's available for this camera system.
As already mentioned, the application of a copper penny across the terminal should cause actuation, if not, its broken or your batteries are not fresh. Batteries must be fresh, I had one fail to actuate and the new batteries from a local camera shop also failed to actuate, swapped out for new batteries from another source and it worked.
Periodically, they get hung up and the only solution is to decouple, actuate and reinstall. Has happened multiple times over the years to me with all of my units and I can't figure out a reason or commonality.
Recently during a wedding I was shooting, hung up on my FM3a, removed from camera and finished the shoot without it. Reinstalled. no problem.
Frustrating motor but that's all there is for this Nikon system.
Frankly the Fm3a is the best Nikon film SLR I have owned, the Nikon F's I've had are indestructible but are old now, the FM series are not designed for the duty of an F but they get the job done very nicely.-Dick