Watch runs perfect for days, and suddenly stops.

[apandersP]

Hello. I’ve got this beautiful Citizen Alarm Date. The watch runs perfect and is really accurate, but it suddenly stops. It can run for days without any issues, but then stops. When it stops, it starts right up again with a small wind. 
 

The hands is not close to each other, and I can’t really find any issues.. 

Does anyone got any advice and suggestions?

The movement is Citizen Cal. 3102

It doesn’t matter how much the watch is winded, it can happen almost fully winded and half winded. 

 

 

 

Edited February 28 by apandersP
Added text

[nickelsilver]

When was it last serviced?

[apandersP]

3 minutes ago, nickelsilver said:

When was it last serviced?

I got it for my dad’s birthday, because it from the same year that he was born. The seller told me it was serviced, my timegrapher reading don’t tell me that it’s need a service. 

[nickelsilver]

What does the timing machine say? In both horizontal positions, and 4 vertical? The fact that it's stopping the watch is saying, "I need a service". Lots of sellers do "servicing" , with the quotes being very important.

[RichardHarris123]

My guess (educated or not) is a rogue particle, lint, swarf etc. It's moving around the movement, occasionally jamming it up, a small wind dislodges it. 

[apandersP]

7 minutes ago, nickelsilver said:

What does the timing machine say? In both horizontal positions, and 4 vertical? The fact that it's stopping the watch is saying, "I need a service". Lots of sellers do "servicing" , with the quotes being very important.

 

[Knebo]

45 minutes ago, nickelsilver said:

4 vertical

This one, too, please ! 

[apandersP]

13 minutes ago, Knebo said:

This one, too, please ! 

 

[Knebo]

3 minutes ago, apandersP said:

 

Still two more missing. 

 But you can already see that something isn't right. 

Even the two horizontal positions are suspicious - the difference in amplitude between dial up and down is too much. 

In the two vertical ones, which amplitude seems ok, the traces are messy. 

I've recently had similar traces when a wheel was out of round (more precisely: not flat) and endshake was way too large on some train wheels. Could be other things. But definitely not in good shape. 

[apandersP]

I’ve got it to run good now. It doesn’t stop anymore. I changed the pallet fork. 
 

But after casing the watch, the alarm won’t work. It worked fine when I made it ring when I should put on the hands. But not after casing the watch.. 

[Simeon]

On 4/16/2025 at 11:53 PM, apandersP said:

I’ve got it to run good now. It doesn’t stop anymore. I changed the pallet fork. 
 

But after casing the watch, the alarm won’t work. It worked fine when I made it ring when I should put on the hands. But not after casing the watch.. 

Not familiar with the Citizen alarm but Poljot alarms operate by striking a post in the caseback to give the vibration.  Did you put the caseback on incorrectly aligned?

[apandersP]

On 5/1/2025 at 4:55 AM, Simeon said:

Not familiar with the Citizen alarm but Poljot alarms operate by striking a post in the caseback to give the vibration.  Did you put the caseback on incorrectly aligned?

It just seems like it won’t work all the time but only sometimes. It is the post version…

I now serviced the complete movement and made it run really good now. It ran for over a week without stopping (of cause I wound it up every morning) and it was keeping time and not stopping. 
 

I gave it back to my dad, and after one hour of wearing it, it stopped again.. I found some hair around some of the posts on the wheels and I thought it was where the issue was.. I’ve got a spare movement for parts, and my thoughts is that my next move would be to change all the wheels.. but I’m kinda lost 

[Neverenoughwatches]

10 minutes ago, apandersP said:

It just seems like it won’t work all the time but only sometimes. It is the post version…

I now serviced the complete movement and made it run really good now. It ran for over a week without stopping (of cause I wound it up every morning) and it was keeping time and not stopping. 
 

I gave it back to my dad, and after one hour of wearing it, it stopped again.. I found some hair around some of the posts on the wheels and I thought it was where the issue was.. I’ve got a spare movement for parts, and my thoughts is that my next move would be to change all the wheels.. but I’m kinda lost 

I wouldn't change anything just yet, trial and error swapping can definitely be a scenario that will get you lost, if you dont keep track, and won't teach you much either.  Carry on with what is already in the movement, go back to basic function group testing.  Start with checking how free the train of wheels turn together ( no balance and no pallet fork fitted ) and examine their shakes one by one, looking for excess. Note if the escapewheel makes some reverse motion as the mainspring becomes fully unwound.

[apandersP]

3 minutes ago, Neverenoughwatches said:

I wouldn't change anything just yet, trial and error swapping can definitely be a scenario that will get you lost, if you dont keep track, and won't teach you much either.  Carry on with what is already in the movement, go back to basic function group testing.  Start with checking how free the train of wheels turn together ( no balance and no pallet fork fitted ) and examine their shakes one by one, looking for excess. Note if the escapewheel makes some reverse motion as the mainspring becomes fully unwound.

So I take the wound of the mainspring as I normally would do, before taking a watch apart. And looking if the escape wheel make some reverse motion? 

[Neverenoughwatches]

5 minutes ago, apandersP said:

So I take the wound of the mainspring as I normally would do, before taking a watch apart. And looking if the escape wheel make some reverse motion? 

Yes, remove all the power first so that the pallet fork can be taken out safely after the balance. Fit the winding stem so you can wind the watch up, don't get into the habit of using a screwdriver to turn the ratchet wheel. While the delicate bits are out of the way, take note of any excess side and end shake in the train, including the barrel. Now wind in a little power and pay attention to how free the train spins. A good indication is when the escape wheel backs up for a second or two at the end. It doesn't necessarily mean that there is a problem if it doesn't do that.

These are checks that you should do naturally during assembly. Saves time finding problems at this stage, rather thsn piecing it all together to take it apart again.