Omega 565 balance staff end shake issue (maybe?)

I am working on servicing a cal 565 from an old & not particularly well cared for SM Cosmic. The movement ran when it came to me, but timekeeping & amplitude were poor.

During disassembly I noticed that one tine of shock spring for the lower balance jewel was unhooked;

Didn't think much of it, but made sure to seat the shock jewel & spring all the way in the reassembly. And now I think I understand why the last guy left it this way...

When dropping the balance in the movement takes off running happily, but then when tightening down the balance cock screw the balance wheel stops swinging. If I unhook the one tine on the lower shock spring then it will start running again. And I don't consider that an acceptable solution.

I have a Seitz tool, but these shock jewels are not friction fit, so wouldn't really know how to make use of that in this case.

Any thoughts from the OF community on the root cause for this bad behaviour or advice on how to remedy it would be appreciated.

Cheers

OK, I will try taking it apart & having a poke at the Incabloc setting with the Seitz.

Thanks!

You would not even need the Seitz. Any staking set will do. Just push the whole incabloc a tiny bit down and see how it changes things.