CLA'd Leica M3 mechanical SNAP sound issue

[AZPhotog]

Hey folks, looking for some knowledge here. I have a Leica M3 (1960) which has been CLA'd not too long ago. If the shutter dial is set to 1000 and then turned down through the speeds to 1/2 and 1 second, as the dial goes from 1/2 to one second there is a loud SNAP sound within the body. HOWEVER - if the dial is first set to 500 or 250 or any other speed and then turned to 1 second, there is NO snap sound. The snap sound is only related to having FIRST been set to the 1000 speed setting. My other M3 (1959) does not do this (also CLA'd), nor does my brother's M3 (1960), also CLA'd. Does anyone know what would cause this SNAP sound? To me, anyway, this appears to be just not right. 😕

P.S. I do not have any photos made at slow speeds yet to test shutter operation at 1/2 and 1 second.

 

[bmiller128]

My M3 (1955 I think) does something similar. It's also only after you turn the dial to 1000, but in my case the snap happens between 25 and 10. As far as I can tell, all of my shutter speeds work fine, but I agree that it doesn't seem right.

Anyway, I'd also be interested in learning anything about why this happens.

-Ben

 

[nobbylon]

The sound you are hearing is the disengaging lever snapping back against the cams below the shutter speed dial.
It is part of the mechanism which controls the slit width to give you the different shutter speeds. I have one here on my bench which does it and I've had a few in the past that have done it. I'm no tech but changing the speeds always frees it and also pushing the shutter release does.

Ok i just checked and the thing that frees it up before every release is advancing the shutter.
Set the camera to 1000 and then gently back to say 250 and then listening carefully you will hear the disengaging lever snap back against the cam.

The cause is the slit width eccentric screw rubbing on the other end of the disengage mechanism.
Has no effect on operation as the cam snaps back to flush when the shutter is advanced and said cam is in such a position when shutter is advanced to not allow the cam to stick.