Problem with Omega 321

There are two different styles of hammer/stop lever combination. The older style has the larger pin on the hammer, and the stop lever with the cut in the end of it, as yours is. Newer style on the left, older style on the right:



Older style in situ:



Newer style in situ:



I can't see if the area where the pin contacts is damaged, but if it's not, then adding some grease there is essential - I use Moebius 9504.

Note that if you have to change the stop lever because that surface really is damaged, it would have to be with the same type, or you would need to change both the stop lever and the hammer over to the newer style. Same if the hammer has to be repalced.

Note that sometimes hard resetting can be caused by other things - wear on the face of the hammer that contacts the cam - I've seen deep gouges in these that need to either be smoothed out or the hammer replaced. Also, sometimes the cam on the hour recording wheel will have a flat spot formed on it over time, and that can cause hard resetting.

So if after checking all those things it still won't work, then I would take a look at the adjustment of the stop lever - it needs to be adjusted just enough to stop the hour recording wheel, and no more. If it's adjusted too much over, it can cause difficult resetting as you are experiencing.

Hope this helps.

Cheers, Al