Hi All,
I get a lot of 321's with hour recorder issues so thought it a good idea to go through some of the root causes.

Disclaimer - This post is not aimed at self promotion, however I see no way to make members aware of the issues without relating my experience in repairing the 321.

The Omega 321 seems to have an awful lot of issues with the hour recorder. It's prone to creep and or lazy and inaccurate resetting.

First obvious issue is the hour recorder creep. This is where despite the chronograph not being active, the 12 hour subdial hand still moves forward.

To me this is one of the surest signs that the movement in question needs a service. You see, what generally causes it is not an incorrect adjustment of the hour recorder brake but rather a lack of lubrication in the clutch mechanism situated on top of the barrel. Too little lubrication = too much friction. Even with the hour wheel brake fully on (think parking brake or e brake in your car) the power from the mainspring is enough to turn it.

The hour recorder wheel CAN have flattened teeth causing slip where it meets the brake but its not common. Also possible is grease/oil in completely the wrong part of the brake, but again not common.

Throw in a weak - and out of stock for years return spring - and there are plenty of 321's with this issue.

Please note in the image below the clutch mechanism is hidden under the hour recorder bridge and is not visible.


Second issue is the lazy reset.

This one often has something to do with both the movement and pusher side of things.

What tends to happen is wear on the friction surfaces of the parts that form a connection between the pusher cap and the hour recorder hammer then subsequently the hour recorder wheel. These things work to prevent proper contact of the hour hammer lever face with the heart cam of the hour recorder and so causing a slow or ineffective reset.

The hour brake is commonly worn on the edge that rubs against the hour hammer lever pin. Wear in this area means there is not enough friction to give the proper 'snap' to the reset and so everything works kind of in slow motion. You press the pusher and the hand slowly returns to 12 rather than snapping back.

The hour hammer can have a worn pin which causes a similar problem. Or too much/incorrect lubrication. Or a rough/dry or both surface where it contacts the heart on the hour wheel.

The operating lever for the hour hammer can be worn at either interface, slightly bent, chipped or the wrong type for the case ( movement swap from a Deville or Seamaster )

Then on top of all this there is the gap between the pusher stem for zero action and the pusher screw. If this gap is too big it can cause the same whole problem all by itself. Important here to note is that the zero action pusher will often get caught up on the movement ring. Also this can cause the recorder to reset off centre.

All of the above on their own or in combination can cause the recorder to reset off centre or in a non consistent manner.

What this problem is not usually caused by is the heart under the hour wheel. Although it can become slightly flattened in some areas from use, it almost never needs replacing provided all the other parameters are corrected properly.



So,.... if you spot a Speedmaster, Seamaster or Deville with the 321 and it has either of these problems, you now know there'll be a whole lot of problem solving needed to make it right. Doubly so if these problems are occurring after a 'Service". If the seller says the hour recorder creep or reset can be cured with a simple adjustment, it almost certainly is not true.

It seems clear to me that a lot of services fail to address these issues, so beware.

I'm not sure how to add video's here or if its even possible but I have examples of the lazy reset and what it should look like when working properly!

Happy hunting!

 

I ran into exactly that problem many years ago when the watch belonged to a friend, now deceased. While the watch belonged to him, I was never able to find out why there was a re-set problem with the hour register hand. Fast forward, and the watch was bought by another friend of mine. He wanted me to service it for him, which I did. When I finished it, I was reminded of the problem with the hour accumulator hand. I puzzled over that problem for a while, and finally, I figured it out. Too much end shake on the hour count wheel meant the hammer was slipping under the count wheel upon re-setting. I used my Seitz jewelling tool to lower the upper bushing on the count gear arbor about 0.05 mm, and that solved the problem.

 

Great post! Were these issues addressed by Omega in the updated designs for the 861 / 1861 movements? Or is it simply a case of 321s being very old and not maintained well?

By the way if you want to add a video to your post you can upload it to Vimeo or Youtube and embed it here.

 

Thats an interesting one for sure! I've had two now where the hour recorder bridge was bowed on that bushing point and another that had a bent mainplate where the bottom pinion of the hour recorder sits. Well done on sorting it out!

 

Hi Kmart, The 861/1861 has the same clutch design, the hour recorder brake and return spring are a bit different but not massively so. The 861/1861 still suffers from hour recorder creep on a regular basis but not so much from the lazy reset.

I'll have a look at posting the videos on you tube. Thank you!

 

Excellent post! More quality, and informative posts like this make this a great forum to be apart of

 

Great insight for a clueless 321 owner.Helps me understand a bit better.

 

Thanks for sharing ! Thanks god haven't faced any of the described issues with my 321's yet but interesting and good to know

 

Have a same problem, now I can tell my watchmaker what to do if his solution won't work! Tnx [emoji482]

 

My 145.022 returned last week from service with an issue it hasn't had before...chrono creep. I assume the 861 and 321 have the same vulnerable spot and my search for a reliable Wacthmaker will continue. I might end up with sending them all to the UK in the future..

 

Very informative read. Thank you for posting!!

 

Just to add to this educational thread, the first thing to understand with regards to the hour recorder is that it's really quite independent of the seconds and minutes recorders. The seconds and minutes are driven off a drive wheel that mounted to the fourth wheel of the movement, and the seconds recorder has a finger that trips the minute recorder. The reset of these two is also completely different than the hour recorder, so this video will show the resetting of the seconds and minutes:

This is an 861 but the principles are the same for the 321 also. I took this video for another reason - to show what happens when the stem bolt for hammer is missing, where the seconds and minutes reset when you press the start/stop button in the first sequence, and then with it in place in the second. On these two recorders the hammer that resets the cams is spring loaded, so as soon as the stem bolt for hammer is moved out of the way, the hammer is forced by that spring to reset the counters. Note that when the chronograph is not in use, the hammer stays on the cams of the seconds and minutes counters to keep them in place (zeroed).

In contrast the hour recorder is driven off a pinion that is connected to the mainspring barrel. The pinion fits over the barrel arbor, and is connected via a friction spring:



So looking under the hour recorder bridge, we see the part marked A is the friction spring on the barrel, B is the drive pinion, C is the hour recoding wheel, and D is the reset hammer:



Note that the cam that is used for resetting the hour counter is on the underside of the wheel when installed, so you can't see it in this shot.

Since the barrel is turning all the time, the friction spring is also turning all the time. If the stop lever (brake) is not engaged, the hour recording wheel will also turn. This is because the hammer doesn't rest on the hour recording wheel's cam like the hammer above does. The hammer for the hour recorder is also spring loaded, but the spring keeps the hammer away from the cam, so once the hammer resets the cam, the spring moves it out of the way, leaving only the stop lever to hold the hour recorder. When you reset the hour recorder you are actually working against the spring, rather then with it like you are on the seconds and minutes counter - again this is an 861 but it shows how the reset works:

Usually the creep is solved simply by servicing the watch - no adjustment of the stop lever is required. If the driving pinion and friction spring are providing too much drive to the hour recorder wheel, no amount of adjusting the stop lever will prevent the creep. Lubrication is the most common reason for this, but also people not paying enough attention to the friction spring that connects the pinion to the barrel is also a fairly common thing in my experience, and this causes too much friction no matter how it's lubricated. The spring often gets worn where it rides on the drive pinion, and when it's replaced you need to check that the friction is not too great or too little:



The resetting issues can have a lot of sources, worn cams and hammers are common - personally I replace these if worn:





This is an 861, but the same issues with the hole in the main plate where the hour recorder wheel locates is common on 321's also - you can see there is a burr there and the hole is slightly oval:



Cheers, Al

 

THANKS FOR THIS POST! MYSTERY IS SOLVED AS LAST!

 

Moderator...this thread is worthy of being added to stickies/archives!!! Please!!!

 

Thank you
Another reason to keep me away from vintage Speedmasters

 

This is exactly why you are my watchmaker and horological advisor.

 

I agree!![emoji106]

 

Sorry to hear that, most likely due to incorrect lubrication of the clutch assembly

 

I 2nd that. Great post