Hour Counting Wheel Assembly - Valjoux 7750

[mcoulton]

Hello

I'm trying to install the Hour Counting Wheel assembly in a Valjoux 7750. The issue I'm having is the Hour Hammer Wheel keeps fouling on the Hour Hammer and the Hour Hammer Counter Lock. I believe it's because the Hour Hammer Counter Wheel is pinned to the Calendar Bridge. The latter prevents me from installing the Hour Hammer Counter Wheel separate of the bridge and seeing how it interacts with the other Hour Hammer components. These are my questions:

1.) Should I take the pin off? The one holding the Hour Hammer Wheel to the  Calendar Bridge?

2.) Can this pin be removed?

3.) Any tips for installing the whole assembly if I'm not meant to remove the pin?

I've included pictures to better illustrate what I'm writing about. Thanks in advance for any help that can be provided. 

[Knebo]

Hi @mcoulton,

I was looking at the manual and my own fotos to understand you problem. I wasn't sure I follow.

But to be sure: when you write "Hour Hammer Counter Wheel is pinned to the Calendar Bridge", are you saying that it's stuck to the bridge? It shouldn't (it should come off easily, actually -- worst case, the pivot is bent). You'd install the wheel onto the main plate, position the hammers/locks and then put the calendar bridge.

I found this video quite good, time stamp added to the assembly of the hour counting wheel: 

 

[nickelsilver]

It looks like the tube (pipe) for the hour counter hand pulled out of the hand and is still on the hour counter wheel. You can pry it off with small levers.

[JohnR725]

51 minutes ago, nickelsilver said:

It looks like the tube (pipe) for the hour counter hand pulled out of the hand and is still on the hour counter wheel.

One of the problems with chronograph hands and whoever manufactured the watch would be that often times they are put on with considerable force. The problem with the amount of force they go on with is that often times when removed they disintegrate. So disintegrating hands unfortunately is quite common on a chronograph. With those lucky enough to have an account with were be authorized by whoever made the watch or the service center they would have a complete package of hands.

so yes that does look like the brass tube of the hand that disintegrated.

 

[mcoulton]

Thanks for the information, its a big help. I'll try and pull off the pipe. I think I'll try using the Presto hand remover. Then I guess I'll try to fit the pipe into the hands(?) though maybe I won't have to as I'm putting a new set of hands on the movement. 

[SwissSeiko]

44 minutes ago, mcoulton said:

Thanks for the information, its a big help. I'll try and pull off the pipe. I think I'll try using the Presto hand remover. Then I guess I'll try to fit the pipe into the hands(?) though maybe I won't have to as I'm putting a new set of hands on the movement. 

This is possible to do, but also can be quite difficult. When I have done it, you have to spread the top of the brass tube to the hand with a staking set. Then you will most likely need to repaint the hand. Its often easier to buy replacement hands, and like stated above, on chronographs the hands are generally viewed as consumables at service.

[Knebo]

2 hours ago, nickelsilver said:

It looks like the tube (pipe) for the hour counter hand pulled out of the hand and is still on the hour counter wheel. You can pry it off with small levers.

Oh damn, yes, that's it

[mcoulton]

Thanks to everyone for their guidance. Just a quick update. I was able to pull the pipe off with a standard set of handset leavers; the pipe was to small for the presto lever. I then installed the whole Hour Wheel Counter assembly including the bridge. Went together in no time (bad pun).