A7750 unwinds itself?

[Drulee]

Figured I'd post this up before heading out, and hopefully have an answer by late tonight

I have an A7750, modified for PAMs (ie. only seconds at 9, and date), that stops occasionally, and often took a bit of shaking before starting up. As I've been feeling a bit adventurous lately, and bought a couple of extra movements (this part being more important ), I decided to see if I could locate the problem.

Well upon removing the case back, I happened to give the rotor a few spins - just because I love that sound. After sending the rotor a few times around clock-wise, I noticed some strange behavior. It seems when it stops its CW rotation, it immediately starts spinning CCW without me agitating the watch at all.

What's up with this? Any ideas? Any tutorials on fixing it? Any hope? I mean there's always gotta be hope, right?

[Justasgood]

Light 6 black candles and immediately sacrifice a fatted calf........then run like hell.

[Drulee]

Tried that already, now I have a large bottomless pit in the basement, and the movement is still isn't fixed.

Maybe I should try sacrificing the neighbors cat, it's pretty fat.

[Drulee]

Morning bump

[Justasgood]

O.k., well usually when this type of thing happens you have a bad gear in the main train or a mis-aligned gear that is allowing the mainspring to unwind. Could also be a broken pivot.

Tabby or Calico?

[Drulee]

Tabby or Calico ??? I'm new at this I just managed to fix my A7750 keyless problem, so I figured I may be on a streak and see if this was fixable.

[Justasgood]

The cat....your neihbor's cat....Tabby or Calico?

As for the watch unwinding....I outlined that before my smart ass question ABOUT THE CAT :-)

[Drulee]

The cat....your neihbor's cat....Tabby or Calico?

As for the watch unwinding....I outlined that before my smart ass question ABOUT THE CAT :-)

I guess you can tell I'm not a cat person, or too familiar with movements

Is it possible to fix while only going so far as removal of the device bridge? Any further than that, and I'll probably screw something up

From a cursory exam of all visible cogs/gears, there doesn't seem to be any damage to them (ie. worn down or missing teeth).

[Justasgood]

With the autowind bridge removed, Slowly wind the watch and while keeping pressure on the crown, ease off of it and watch the gearing. See if any of the wheels aren't engaged. Chances are, it is the wheel that is nearest the Pallet fork and balance.

I have had no luck in dealing with A7750's.

Perhaps The Zigmeister or others can further this discussion.

Merry Christmas and good luck,

Kurt.

[kbh]

I sent my Ebel off for the same problem and the watchmaker said it was a dirty, sticky reversing gear (or something like that). He fixed it for free and sent it back. Said it's a common problem with the A7750. Obviously it didn't take much time to fix.