Leica M4-P strange winding/shutter problem

[papaki]

I have a Leica M4-P looking very good but having a strange problem.
With some films, especially with those I have rolled, when I wind on to the next frame the shutter button is blocked. I have to push the wind lever a bit to get the shutter button to push and release the shutter. This happens on three to five frames on a 36 exposure roll. It does not happen when I wind to the next frame in two stroke fashion.
It never happens without film.
I know that this calls for a CLA, but what could be the cause of it?

 

[Vickko]

My first guess is that the gearing has slipped just a touch to cause this to happen. The gearing and "end of motion" interlocks all have to happen correctly, for the interlocks to clear.

If you look up the film chamber, you might even see one of the interlock cutouts at the top of the film take up spool. With no film, there is no backwards force on this spool, so the notch cutout always goes to the right spot.

With film, the tension pulls back and if the notch isn't in the right place, it prevents one of the interlocks from allowing the shutter button to depress.

A knowledgeable tech can fix this in a jiffy.

Good luck.

Vick

 

[papaki]

Thank you! I will send it right away for repair. Glad it is something as easy as that. Of course it will not be something for me to try.