ETA 2541 endshake problem

[Bill241]

Hi, 

I have been working on an old inexpensive watch fitted with the 2541 movement, to learn the features of this ubiquitous design. 
 

The reassembly went fine, but the watch keeps stopping. Besides an issue with the autowinder reverser wheels (remedied), I determined that the fourth (seconds) wheel has too much endshake. As such, it is coming into contact with the third wheel, and stopping the watch. 
 

The endshake issue would appear to be on the dial side (I don’t see how adjusting the jewel on the train bridge will help, as that will simply push the wheel down on to the third wheel. I can’t see how the dial side tube (the centre seconds pinion goes through it) can be adjusted. 
 

Any thoughts or suggestions would be welcome. I am wondering if a NOS replacement fourth wheel is the way to go. Perhaps there is wear on the ‘shoulder’ of the centre seconds pinion? Or do I need to replace the whole mainplate? 
 

Many thanks. 
 

Bill

[VWatchie]

On 3/29/2023 at 8:55 PM, Bill241 said:

I determined that the fourth (seconds) wheel has too much endshake

If the end-shake of the 4th wheel isn't too bad you could possibly instead move the 3rd wheel a bit away from the fourth wheel. If the end-shake of the 3rd wheel is already good you would have to adjust both jewels equally.

As a rule of thumb, the end-shake for small pivots should be approximately half the diameter of the pivot and about 1/3 of the diameter for large pivots .

[Nucejoe]

 End shakes should be adjusted so nothing rubs and the watch works, even if this requires moving every single jewel. 

 

 

[Bill241]

Many thanks. I found a parts list for the 2450 series of movements and spotted the centre seconds pipe, which is actually detachable and friction fit. I think the similar arrangement on some old Seiko movements are riveted in. I managed to get the old one out with a pin vice and the new one in with a jewelling tool. So far everything is running well again. 

[Nucejoe]

On 3/29/2023 at 11:25 PM, Bill241 said:

The endshake issue would appear to be on the dial side

Did you mean SIDE SHAKE ?