The original Mk. II is a Cal. 861, but the current Mk. II uses a Cal. 3330 co-axial movement, based on the 7750 as I've already written in this thread.

Letting the chronograph run all the time on a vertical clutch chronograph is not a good idea, as it will eventually cause the chronograph wheel to seize, and when you stop the chronograph it will cause the watch to stop, like this:

Some chronograph wheels are serviceable, but many are not and must be replaced. I don't service Seiko's anymore but when I did the chronograph wheels were already getting hard to find, so advising people to run the chronograph all the time is IMO dubious advice.

As I've noted previously in other threads on this topic, it should be stopped periodically to ensure that it doesn't seize together.

Cheers, Al

 

Yes, the runner get gummed and wears out- fact of life. Machines wear out, Tribology is that science.
Theres a reason some brands have had enormous problems with their vertical clutch chronos like Rolex, breitlings B01, and others.
Now Archer has opened a market opportunity for some smart designer to blueprint and get a company to make seiko 6139 runners. But now nobody gets Rolex or Breitling parts really anymore, so those are next on the list.
I apologize that I missed you were referring to the brand new markii watches. I am not really paying attention to anything new from the swiss as it is so tiring to keep track of. Omega wants me to come in for 3-level coaxial training this year but I dont see those watches, and parts for the new 8500-8520 are almost 3-4x higher than the previous generation parts.

 

Generally to a customer or owner the statement is:
"It CAN be left running, and will not affect the timekeeping overall" but still I always advise against running it unless its a DD module like a speedy reduced auto

 

While I appreciate all of the technical references, they are completely lost on me. I remain confused with the conflicting data and advice

 

This means nothing to me, but I found this on the web:

The Omega 3300 is based (well, “inspired by” would be better) the Piguet 1185, as many specs are different (not the same diameter, not the same frequency, not the same escapement…). However, the 3300 is an interesting movement, with interesting features (antimagnetic and co-axial escapement, automatic winding, column-wheel, 52 hours of power reserve and COSC certified).

Can you please confirm one way or the other what this means as relates to my original questions? Thanks guys.

 

Nothing. 3300 3330

 

https://monochrome-watches.com/omeg...aph-co-axial-hands-on-with-live-photos-price/

 

Great - what this proves is that watch bloggers are lazy, and copy each other spreading the same misinformation.

The Cal. 3330 is not based on an F. Piguet movement...period.

It is a horizontally coupled chronograph based on the Longines L688, which in turn is an ETA/Valjoux 7750 movement modified to use a column wheel. But it is still horizontally coupled, and that is done via a part called an "oscillating pinion" that moves in and out horizontally to engage the chronograph wheel. This video shows it on the 7750:

I've tried my best to help answer your questions, but if you prefer to listen to the bloggers, that's your choice.

Cheers, Al

 

Don't be offended. I clearly have no idea what all of this means and the link was simply intended to provide context for my previous post. I appreciate your time, knowledge and input and absolutely believe and accept your response. Thanks very much for your time and assistance.

 

Not offended, just tired of fighting the misinformation that’s been out there on this movement for the last 7 years...

 

Wait a minute!!!! So letting the chronograph running constantly on the new Omega 9300 movement can/will cause problem with the chronograph wheel to seize????

This is contrary to what I was hearing that it is OK to leave the 9300 chrono running constantly.

 

Who!!! were you hearing this from??????????????????????????????

 

Sarah Sanders.

 

Sarah Huckabee Sanders.

 

Various result from internet searches.

https://www.google.com/amp/s/forums...y-come-also-help-me-decide-1078499.html?amp=1

 

Also recalled one of the guy at the Dallas OB saying you can leave the chrono running when I was looking at the DSOTM.

 

Then leave it running...

 

Not trying to argue against you. Just wanna know what is real vs misinformation.

 

I would consider the source: guy at Dallas boutique, or an experienced, respected watchmaker. I don't see the dilemma...

 

Hmmmmm.... Hmmmmm....

(Especially when he shows the video of the problem occuring)