Help wanted with Omega Cal 620

[Alaskamick]

I have an Omega cal 620 which is only about 17mm dia so quite small and being inexperienced with wrist watch work I'm loathe to completely strip it down.

When I pull the crown out it just pulls right out of the movement complete with the stem. My immediate thought was that the pervious owner had fitted the wrong stem.

I got a new stem and fitted it but it still puts out even though the release crew is tightened up.

It's pushing in to a dead stop so my thoughts are that the end of the original stem has been broken off and left inside.

It doesn't seem to go in far enough for the lever to pull into the cutout machined in the stem.

Any ides how I can ascertain exactly what is wrong without a full strip down.

[jdm]

2 hours ago, Alaskamick said:

Any ides how I can ascertain exactly what is wrong without a full strip down.

X-rays?

[rogart63]

You could try to measure with something. A needle? Put it in where the stem should be and mark it . Then you could compare that so the new stem. Just a thought? 

[Alaskamick]

The new stem is identical to the one which came out. I think something is stopping them going in full depth.

[Marc]

Have you tried loosening the set lever screw (to the left of where the stem enters the movement) by about 1 to 1 1/2 turns, and then keeping a little pressure on the head of the screw as you insert the stem?

This moves the set lever out of the way of the stem so that the stem can pass into its correct position.

Don't loosen the screw too much though otherwise the set lever screw will come out of the set lever alltogether and you will have to remove the dial to reset the keyless works.

[Alaskamick]

Thanks a lot Mark. I unscrewed it about two turns. Then did as you suggested and after tightening the screw again the stem was locked in place.

All the previous stems I've fitted just pushed right in with the screw as you say 1 to 1 ½  turns.

I can now get on with putting the watch back together so have a "gold star" from me.

[Alaskamick]

Can someone tell me how to put a solved message on this post with the green highlighting ?

[Marc]

[Geo]

22 minutes ago, Alaskamick said:

Can someone tell me how to put a solved message on this post with the green highlighting ?

I've asked the boss about this one for you.

[mikepilk]

I finished cleaning an Omega 620 recently - smallest watch I've cleaned so far, those balance cap jewels are tiny !

I found that the release screw for the stem took about  2.5 turns, and then I had to push on the screw, before it freed the stem. 

I thought it was odd at the time that it took so many turns, but as I was stripping it I wasn't worried about it coming out of the lever. From what I remember, it took well over 3 turns before the screw came out of the lever.

 

 

To give an idea of size, that's a 1p