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Can anyone diagnose my A7750 Chrono Problem?


EMM

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I was wondering if any of the experts could instruct me as to what’s going on with this Corum America’s Cup chrono.  
 
It’s an A7750, and simply put, the chrono doesn’t start.  The 1:00 pusher also doesn’t have a “click” to it.  The 4:00 pusher actually feels fine, but unless the other one works, AFAIK there’s no way to tell if the 4:00 pusher works.
 
Anyway, I took some crappy iPhone pics of the movement to hopefully help in the diagnosis.
 
Here’s the area where the 1:00 pusher does its thing.  Really nice that it’s 48mm – lots of room to see.
 
 
photo5-1_zpse21f8cc5.jpg
 
OK, I think part of the problem might be with this thing in the pic below.  There’s a piece that straddles the side of the movement, and it’s what the pusher hits when you press it.  There are some odd things going on here.  First, the circled portion in the pic below pivots around the place where it attaches to the rest of the piece – you can turn it back and forth.  It’s got a notch cut out of it on the other end.  Don’t know where it goes, and don’t know if the piece is even in place, although it looks like it.  
 
Next, there’s a spring I drew in green that sits next to and underneath the piece.  It seems to be part of what the pusher is hitting to start.  I tried pushing it with a screwdriver but I never got the chrono to start.
 
photo5-2_zps24a1eea0.jpg
 
Here’s a blow up of the area if it helps:
 
photo1_zps64e2efbe.jpg
 
Any thoughts on the problem?
 
 
Thanks!
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Well, it looks like that part I circled in the last pic is the problem.  It pivots around the red dot.  If I put it in the right place, everything works for one push.  Then I have to pivot it around to the right place again each time.  It's really loose - does something hold it in place or is it just worn out?

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