Leaderboard

I am inclined to agree that you may have just about nailed it! I was contemplating on the click and the escape wheel! The movement ran 24 hours really well on a close to full manual wind ( just with enough turns of the crown to avoid the slip) without the automatic assembly . As soon as I wound it fully with an extra couple of turns, it stopped just a few hours later ! I then jiggled the balance and seemed as it had locked as if Impulse jewel had misaligned, but I then realised it wasn’t the case ! I noticed that it had just enough swing to slightly rock the pallet fork as balance wheel was swinging very rapidly backwards and forth with no real action! I then jiggled the escape wheel with a fine oiler and bingo it fired uo! So my guess is that the impulse jewel never got out of line at all as if it were the case, then the movement would not have run! Right? Unless there is something I do not know about impulse jewels and the balance wheel/pallet fork combo! Your other information has indirectly helped me solve an issue with two other movements which had me baffled for months if not close to years! Great suggestions and highly appreciated! Something you would not get on some watchmaking forums! A world of thanks!

If the mainspring is slipping, then most likely either the spring is slipping on the mainspring arbor, the click or click spring may be loose or defective, or the escape wheel is slipping past the pallets. If you left the pallets in cleaning fluid too long, it is possible they may have shifted out of position, which could result in the escape wheel slipping -- & intermittently unwinding the mainspring as this occurs. Unfortunately, I know of only 3 ways to verify this type of problem -- replace the pallets with a new (or known good) set, put the movement on a timer with recorder for 24 hours & watch for telltale signs of slippage in the readout (eg, a sudden & significant drop in an otherwise regular pattern), or sit & watch the movement until it slips & see if you can see where it is slipping. Since this is a 2783, I think the easiest avenue would be to replace the pallets since they are not expensive (here is a new 1 on ebay for $12).

Presuming the entire movement is clean/properly oiled/demagnetized -- it sounds like either the cap jewels are dirty/worn (remove/inspect/clean/oil), the balance cock/bridge is not properly seated or the hairspring is hanging-up on an adjacent component (ie when the movement is moved/shaken). If/when you eliminate the 1st 2 issues, I would remove the balance, remove the hairspring from the staff (use a small screwdriver to slide the hairspring collet off the staff) -- then re-attach the loose hairspring to the cock/bridge & allow it to sit on top of the cock/bridge. Inspect the hairspring's positioning for flatness/proper centering over the cock/bridge (if the collet does not naturally sit directly over the cap jewel holder in the cock/bridge, you will need to reshape the hairspring so that it does). There is a good guide on TZ that you may find helpful. Correct as needed or post a few macros of the hairspring (attached to & sitting on top of the cock/bridge) so I can see its condition/position.