Longines Cal 550 Removal of Stem

[eddieimps]

I am struggling to work out the removal of the stem from this movement? I am usually quite adept at this especially with Oegas, but I am a little lost on this one!

[RichardHarris123]

Take a clearer photo of here  

[eddieimps]

Does that help at all?

[RichardHarris123]

No, hehe but I think it might be the stem release button .

[eddieimps]

Thats what I thought, but its not, or at least it wont release the stem.

[JohnR725]

what about this other thing it looks interesting?

the problem with vintage watches is finding anything at all that resembles  technical. It does look like the 505 is based on the 501 although the 505 parts list hard to tell but it looks like the part that I marked in the above image still looks interesting and unfortunately we don't have a text description of what that part is

Longines_Longines 501.pdf Longines_Longines 505.pdf

[RichardHarris123]

Here's a clearer view, I think it's a 505 not 550. 

[AndyGSi]

1 hour ago, eddieimps said:

Thats what I thought, but its not, or at least it wont release the stem.

What position is the crown in when depressing the dimple as some need to be in the setting position.

[JohnR725]

48 minutes ago, AndyGSi said:

depressing the dimple

just to be clear here there are two dimples and this one in the circle I think is the wrong one even though it looks right

unfortunately I don't know how to make nifty symbols like pretty circles so I will just freehand draw I think this is the dimple that needs to be pushed

notice I circled two separate things? The pink thing which looks like a button appears to have a piece of steel underneath it that's the larger thing I circled its held in place by a screw. I'm guessing that's holding the button up and that you can push it down as it does look like a dimple for pushing.

 

[AndyGSi]

8 minutes ago, JohnR725 said:

just to be clear here there are two dimples and this one in the circle I think is the wrong one even though it looks right

unfortunately I don't know how to make nifty symbols like pretty circles so I will just freehand draw I think this is the dimple that needs to be pushed

notice I circled two separate things? The pink thing which looks like a button appears to have a piece of steel underneath it that's the larger thing I circled its held in place by a screw. I'm guessing that's holding the button up and that you can push it down as it does look like a dimple for pushing.

 

Looking at the parts that's the pressure spring for the setting lever so sounds right.

[eddieimps]

MM, yes tried that. Doesnt want to budge at all.

[eddieimps]

I only want to replace the crown!!!

May have to take it to a watchmaker.

[AndyGSi]

So does the dimple to the right of 'swiss' move at all when pressed?

[eddieimps]

On 4/16/2025 at 7:23 PM, AndyGSi said:

So does the dimple to the right of 'swiss' move at all when pressed?

It seems to depress. And on something like an omega its a really simple job, just about to try with the button in as apposed to set. So frustrating as I actually have the right crown! And in all other respects the watch is a great example!, not sure its ever seen intervention, but I guess it must have because it has a new unsigned) crown! Prize for the first person who provides the solution!! I have added more images, sorry for the quality, best Samsung can manage in Macro mode.

[eddieimps]

Stop Press.

It is done.

It was the suspected button, but it was very gummed up. A very small amount of brute force (not really) and some persistence, hey presto.

 

Thank you all for chipping in.

 

Kind Regards

[JohnR725]

On 4/15/2025 at 12:47 AM, eddieimps said:

Thats what I thought, but its not, or at least it wont release the stem.

if you push the button does it pushed down does it move what exactly does it do?

I thought I'd look on YouTube not overly helpful but it does give a clue of what the dial site looks like and the button does look like it's in the right place?

the problem with YouTube in a variety of other places would be the lack of words like 505 and the inability of the searching to actually find a 505 so there may be more videos somewhere but I'm not finding them and this one really is an super good but it's the best we have so far