Help with a Automatic

[alvaropinto]

Hi there,
I've been most of the time surfing trough Omega threads but suddenly realized I have this Zenith automatic for some time now which I now very little about.
Dial with considerable wear and movement also a bit worn. My watchmaker ( a wonderful old magician), got it serviced and running quite accurately ( gains less than 20 seconds/day). I'm not familiar at all with Zenith automatics and would like to know your thought on this one.
Cheers!

 

[ulackfocus]

Oooo, a bumper 133!

A couple of the members have various incarnations of that, including LouS's sweet chronometer 133.8 gold model.

 

[alvaropinto]

A bumper indeed. By the way, the pics are prior to the watch being serviced and the missing rotor spring was replaced.

 

[LouS]

The Zenith bumpers (133, 133.8 and 71) were creations of Ephrem Jobin, the same man that designed the observatory competition monster the cal. 135 (http://omegaforums.net/threads/who-was-ephrem-jobin.2807/). They are excellent movements, but a developmental dead end, as Zenith switched to Martel's rotor automatics as soon as it acquired that firm in 1960.

The 133 differs from the 133.8 in the beat rate. The 133 runs at 18,000bph and the 133.8 at 21,600bph. THere are a few other differences in detail but they are fundamentally the same movement.

 

[Stewart H]

LouS

The Zenith bumpers (133, 133.8 and 71) were creations of Ephrem Jobin, the same man that designed the observatory competition monster the cal. 135 (http://omegaforums.net/threads/who-was-ephrem-jobin.2807/). They are excellent movements, but a developmental dead end, as Zenith switched to Martel's rotor automatics as soon as it acquired that firm in 1960.

The 133 differs from the 133.8 in the beat rate. The 133 runs at 18,000bph and the 133.8 at 21,600bph. THere are a few other differences in detail but they are fundamentally the same movement.

...... and not forgetting that the 133 has the springs mounted solidly, whereas the 133.8/71 had the springs on the oscillating weight.

 

[alvaropinto]

Thanks a lot for the information guys!
When was this automatic introduced? Was it after 135?...mine looks from around 1948.