Watch Works; Has A Rogue Screw...

[frenchie]

I know someone with an eterna-matic 3000 that was working fine and that suddenly just stopped working. It's a very nice watch btw, super thin. Anyways, he asked me to take a look at it (there is no way I'm doing anything to this watch with my skill level, but I couldn't resist taking a look at it :phew: ).

 

I popped the back open and immediately noticed that something was blocking the balance. I pulled this something out and it turned out to be a small screw... As soon as I pulled it out, the watch started ticking like a champ. Everything seems to be in working order and it seems to be keeping good time. It ran for about 16 hours before stopping.

I know the owner would like to wear it but right now he is too broke to spend $$$ to get it fixed.

 

I'm tempted to tell him to save up and get a pro to look at it, and not wear it or wind it in the meantime. Thoughts ?

[autowind]

An Eterna-matic is a really fine watch,  could you take a biggish picture of the movement and post it as someone might be able to spot where the screw is supposed to go.  Put the screw somewhere it will not get lost. 

[frenchie]

Finally, some pics. There are no obvious screw holes missing a screw anywhere that I can see without taking anything apart.

 

A bit more info : the last time it was opened was to replace the stem (and they didn't even use a genuine one... sad). And they scratched the back of it when opening it...