I just dug this 145.022-69 transitional pre-moon Speedmaster out of storage as I am thinking of selling it. It winds and keeps good time and the chrono starts and works well but when you press the top chrono button again it stops the chrono and resets it to zero instead of just stopping it. Photo of movement shown below. I would really apreciate it if anyone can tell me what the problem might be and if it is an easy or difficult fix - Thank you. (Btw this nice Speedy has some of the tastiest dial lume colour I have seen - check out the photo)
I've had this when the lower pusher was stuck down slightly. I notice that from the picture the pin on the lower pusher looks to be pressed up against the movement, which may have the reset permanently engaged. I've also seen this when I fitted a replacement pusher and the pin was too long and therefore it was constantly reset
The part called the "stem bolt for hammer" is broken. I can see it's missing in the photo - not uncommon at all. This is a slender part that is round - like a stepped pin. Here is a photo showing where the pin should be at the red arrow: The part itself is not expensive, but the real trick is finding both halves of it. Sometimes it's impossible to find both halves of it and the only way to find it for certain is a full disassembly of the movement. Here is one example of one that I was servicing with this problem - part at the red arrow is 1/2 of the part" Here is one where the one half could be seen easily through the display back: But the other took some digging for sure: Unless both parts of this can be found, the movement will have to be disassembled to find them. If you are doing that, you might was well service it. Hope this helps. Cheers, Al