OMEGA Speedmaster Date Original Watch Movement Calibre 1155 – 17 Jewels
Omega Speedmaster Date original watch movement calibre 1155 – 17 Jewels from 1991.
Between the 861/1861 and the newer ETA/Dubois-Depraz movements, Omega used the 7750 Valjoux for a while. This is the one of the most popular chronograph movement the Swiss watch industry has on offer, with a unidirectional winder and a click spring construction, and you can find it in many other Swiss watches.
The key distinguishing features of the 7750 family are as follows:
Subdials at 6:00, 9:00, and 12:00 for hours, running seconds, and 30 minute chronograph counter, respectively
Conventional integrated center-mounted automatic winding in one direction
Cam-controlled chronograph functions
Simple three-plate brass base:
– Calendar plate with modular components
– Main plate with off-center center wheel, hacking lever, and simple bent-spring ratchet
– Top plate with additional winding bridge
Etachron regulator and balance spring stud
The Omega calibre 1155 automatic movement is based on the automatic chronograph 7750 Valjoux and it has a lever escapement, 17 jewels, mono-metallic balance, 28,800 BPH, Incabloc shock absorber.
The movement has overlapping circular patterns “œil-de-perdrix” finishing, the oscillating weight is decorated with “Cotes de Geneve” stripes and is engraved Ω | OMEGA | 1155. The movement is marked 17 JEWELS | SEVENTEEN | SWISS, 7750, the ETA logo and PJ in a circle.
The layout is the standard 7750 Valjoux layout with small seconds at 9:00, chronograph seconds by central watch hand, 30 minutes at 12:00 and 12 hours at 6:00. The date opening is at 3:00, with black numbers on a white disc.
The movement works well and is keeping a pretty accurate time. As for any other vintage or unused movement, a basic revision is recommended.
The article is sold as is any other parts that are not mentioned in the description or shown in the photos are not included with this movement.
All the movements in our offers are original service or replacement parts meant to be used by professionals for watch servicing. The movements are handled and stored in different boxes or containers, operations that may affect their accuracy. These movements are supposed to be cleaned, oiled, timed or adjusted by a professional before fully corresponding to the manufacturer specifications.
ca. 44 hours
Chronograph, Date Window