Vintage Timex only runs when face down

[GregG]

Hello all.

Last night i serviced a Timex M25 movement.  Everything went smoothly, and the balance was beating with a healthy amplitude until i turned it right side up.  I reattached the hands, but after 5 minutes or so, the watch stopped ticking.

I searched the symptoms on Google, and the replies generally fall into two categories:

1) check balance end shake 

2) check balance pivots 

Having done several M25s and M24s (identical with the exception of a date function) before, nothing about the appearance or feel of the end shake appears incorrect.

Everything was lubricated according to the service manual.  The hands don't appear to be obstructing each other as the hands can all be in different places when the watch stops. It's not as if the second hand is getting caught up on the minute hand.  However, i will remove the hands anyway to check this.

I will attempt to disassemble it again this weekend, but i try to keep disassembly of Timex's to a minimum, since removing the dial involves bending metal tabs, which may eventually give way to metal fatigue.

Any suggestions are appreciated.

Thank you.

 

 

 

 

 

 

 

 

 

 

 

Edited June 17, 2021 by GregG

[JohnR725]

6 hours ago, GregG said:

Last night i serviced a Timex M25 movement.  Everything went smoothly, and the balance was beating with a healthy amplitude until i turned it right side up.  I reattached the hands, but after 5 minutes or so, the watch stopped ticking.

 

6 hours ago, GregG said:

I searched the symptoms on Google, and the replies generally fall into two categories:

1) check balance end shake 

2) check balance pivots

the problem with searching online is, is this a normal watch? This is a Timex watch what type of pivots does the balance wheel have? then just to refresh everyone's memory I'm attaching an image.

Normally on a problem like this if you have a bad pivot it will basically be almost instantaneous it does not take five minutes to come to a stop. Unless it just slowly comes to a stop when you're not paying attention. then typically if you have a broken pivot and you turn it over it may not run very well and it will come to a stop really fast but not over five minutes but this isn't a normal watch is it?

the problem is it may not actually be the hands causing a problem. In other words you turn the watch over you go to put the hands-on at some point in time you notice your watches come to a stop. So in a watch is running really nice style down turn it over and look at the balance wheel and see if it just slowly comes to a stop. Then take the balance out look at the pivots and make sure the top and bottom look the same. even though these are normal pivots there are still supposed to have a shaped to them and it's possible the watches running with zero lubrication or worse it ever got wet and it has rust rust is a great grinding compound you may just have a bad pivots. So putting the hands-on was incidental if you turned it over and left it running it would just probably come to stop anyway if it is bad pivots perhaps.

 

 

 

[GregG]

Thanks John, I suppose my original post could have led to the assertion that the hands are causing it to stop, but that wasn't my intent.  What I mean to say was that I reattached the dial, attached the hands, crown, case, crystal etc, and then monitored it while it was face up.

But I suppose I can take another look at it this weekend.  Thank you.  I'll take pictures if possible.

[GregG]

7 hours ago, JohnR725 said:

 

the problem with searching online is, is this a normal watch? This is a Timex watch what type of pivots does the balance wheel have? then just to refresh everyone's memory I'm attaching an image.

Normally on a problem like this if you have a bad pivot it will basically be almost instantaneous it does not take five minutes to come to a stop. Unless it just slowly comes to a stop when you're not paying attention. then typically if you have a broken pivot and you turn it over it may not run very well and it will come to a stop really fast but not over five minutes but this isn't a normal watch is it?

the problem is it may not actually be the hands causing a problem. In other words you turn the watch over you go to put the hands-on at some point in time you notice your watches come to a stop. So in a watch is running really nice style down turn it over and look at the balance wheel and see if it just slowly comes to a stop. Then take the balance out look at the pivots and make sure the top and bottom look the same. even though these are normal pivots there are still supposed to have a shaped to them and it's possible the watches running with zero lubrication or worse it ever got wet and it has rust rust is a great grinding compound you may just have a bad pivots. So putting the hands-on was incidental if you turned it over and left it running it would just probably come to stop anyway if it is bad pivots perhaps.

 

 

 

So I was actually mistaken.  The watch will eventually stop when running dial-down.  I guess I just didn't catch it.  But I watched it operate.  It's ticking very strongly for about a minute, then dies down in a few seconds.  I captured a video for you to watch.  Skip to around 40 seconds.  Sorry about the poor quality, I had to zoom way in and the lighting is not great.  I don't hear the "horse galloping" normally associated with rebanking, but I can hear a slight ping on every tick.

However, on one of the times that I ran it, I sat under it as I held it dial side up.  I noticed a distinct knock into something, as the balance came to an immediate halt.  I suspect the impulse pin actually made a full rotation and smacked into the end of the pallet fork.

 

Edited June 18, 2021 by GregG

[GregG]

Another observation, as it's beginning to fail, the escape wheel stops rotating.  And the pallet fork just keeps ticking into the same teeth.  Might be down to a lack of lubrication, so I'll try to give them another dab of oil.

Edited June 18, 2021 by GregG

[JerseyMo]

this is a common issue with vintage Timex.  Given that these movements rarely were lubricated after the factory the most likely issue is wear to an one or several of the pivot points.  Have a look with a 10 or 20x loupe while things are in motion and you may see a that post point is more of an oval shape rather than round.   

 

[GregG]

15 minutes ago, JerseyMo said:

this is a common issue with vintage Timex.  Given that these movements rarely were lubricated after the factory the most likely issue is wear to an one or several of the pivot points.  Have a look with a 10 or 20x loupe while things are in motion and you may see a that post point is more of an oval shape rather than round.   

 

Thanks Mo, I'll take a look tonight.

[Nucejoe]

   Pivot is not staying in v conic bearing, check the pivot and V conic bearing. if undamaged you should reduce the end shake perhaps by moving the bearing. 

[JohnR725]

1 hour ago, JerseyMo said:

this is a common issue with vintage Timex.  Given that these movements rarely were lubricated after the factory the most likely issue is wear to an one or several of the pivot points.

unfortunately this is a common problem with any mechanical device that runs for a very long time without regular maintenance. Things like automobiles people usually grasped that the need to get the oil changed occasionally and maintenance has to be done.

watches really fall into a weird unique category of people failed to grasp that they need to be maintained. Once we get into modern synthetic lubricants that typically do not gum up. we have a situation where a watch will continue to run long after the lubrication is no longer there until finally the watch stops. Metal on metal bearings will wear watches can literally wear themselves out over time. Timex watches all metal on metal. Which means they're going to suffer from a long life of lack of maintenance.