Movement runs but eventually minute and hour hands stop

[Chopin]

I have a Favre Leuba with a FL 1164 movement. It came with this problem and I decided to service it thinking it just needs a service.

The only thing that I noticed is that one tooth of the hour hand gear/wheel is slightly bent but from my verifications it seemed fine.

The movement is serviced and put back together and it runs but at some point the minute and hour hands just stop. The movement keeps going though, so does the seconds hand.

I'm still doing all sorts of troubleshooting to see what the problem is exactly. I don't think that it stops at the same time, all the time, so I'm not sure if the problem is the gear's tooth.

Any pointers or help ? What are the possible issues here ?

I removed the hands and then the dial. I put back just the minute and hour hands it stopped again after a few hours... I removed the minute hand (thinking that it might be a problem with that one) but it still stopped.

Now I'm waiting for it to stop and see where it stops... Here's a photo before service and total disassembly.

There's another gear (for one of the disks; already removed in this photo) that's covering the area where the hour gear meets another gear so I'll remove that at some point and check if the movement stops somewhere in that area.

Edited June 26, 2018 by Chopin

[ecodec]

Difficult for me to be specific but I do not like the bent tooth on the hour hand gear wheel.  Tooth damage can be a real problem. Make Sure it is quite Free to mesh. Damaged dial train teeth etc: ? Is the minute wheel in good condition ?  Would not be something as simple as a dial washer required to keep the hour hand wheel from rising up too much out of mesh with the minute wheel pinion would it ?  Check the canon pinion. I am not a watchmaker,  just a jobber but I hope this is of help. Best regards, Mike.

[Chopin]

It has no dial washer but I have kept the movement running without the dial and it still does this.

All parts are in good condition.

I've done all sorts of verifications on that gear and the other gears around it, kept rotating them around in various combinations and scenarios and it looked fine but I don't know...

Normally if it stops it should stop only when the bent tooth comes up in relation to the gear that is supposed to rotate it.

Will try and take a pic tomorrow of the bent tooth. I know that it can be tricky and risky to have it straightened.

The gear that turns the minute and hour gears has this dumb system of staying inside the movement. As can be seen in the photo, instead of having the pinion of the gear go into a jeweled hole (or even a normal hole) it will, partially, stay in place thanks to a spring.

Coincidentally I encountered the same system on an AS movement that I worked on a few weeks ago. This movement might actually be based on that one as the similarities were striking.

Edited June 26, 2018 by Chopin

[ecodec]

On 26/6/2018 at 10:23 PM, Chopin said:

It has no dial washer but I have kept the movement running without the dial and it still does this.

All parts are in good condition.

I've done all sorts of verifications on that gear and the other gears around it, kept rotating them around in various combinations and scenarios and it looked fine but I don't know...

Normally if it stops it should stop only when the bent tooth comes up in relation to the gear that is supposed to rotate it.

Will try and take a pic tomorrow of the bent tooth. I know that it can be tricky and risky to have it straightened.

The gear that turns the minute and hour gears has this dumb system of staying inside the movement. As can be seen in the photo, instead of having the pinion of the gear go into a jeweled hole (or even a normal hole) it will, partially, stay in place thanks to a spring.

Coincidentally I encountered the same system on an AS movement that I worked on a few weeks ago. This movement might actually be based on that one as the similarities were striking.

Well Chopin, you have me beat, having checked it all it is a mystery. You may be able to clean that bent tooth up a little with care  and some 1500 paper to make sure the teeth mesh smoothly. There are well experienced people here so perhaps they can help.

[anilv]

DId you check for free moment of the train with balance wheel and pallet fork out? They should wind down smoothly and once stopped they should not much much further if helped along with an oiler or pointed tool.

You also need to check why the hour wheel got bent in the first place. Check the interaction with the minute-wheel and the intermediate winding wheel.. if this is sticky then the watch will stop.

Anil

Edited June 27, 2018 by anilv

[ecodec]

anilv, Good idea, it is beginning to sound like a train gear problem. Check the going  barrel teeth as well. I wonder if the teeth are free and undamaged in the train area. Your test would be a good one !. I did have an old JLC pocket watch in for repair with teeth damage where someone had tried to make it GO pushing the train round with a screwdriver !! Needless to say I begged to be excused. One does wonder how that tooth got bent? Good wishes Chopin.

 

[Chopin]

Great advice guys especially checking the movement without the pallet fork and stuff. How come I didn't think about that one ?

Anyway, I have a suspicion that it's not the hour gear because the movement seems to stop after a few hours or so and not at a certain specific time, all the time.

Will come back with some updates today or in a few days. Thanks!

[vinn3]

Quote

" pushing a gear with a screw driver"  is a great temptation. !  with the balance out,  the gear train should with one or two turns of the winder.  if this does not happen or it stops during wind down,   it might need lube or removing the main spring.  good luck.  vin

 

[Chopin]

Alright so coming with a small update. At this point I believe that the bent tooth might not be the issue here.

I've removed a few parts so that I can test the gear train as you guys said.

Apparently if I move the mainspring around the gears will only rotate a little bit. I have the hour hand installed so it only seems to move about an hour or so in either direction then the gears stop even though I'll keep moving the mainspring around (and various other gears in the movement will also continue to move).

I've manually rotated the gears so that I can test this thing in multiple positions and it does the same thing.

I've just taken a photo of the culprit.

As I said in an earlier post part A is the one that drives the minute and hour wheels and the system that they used to make it sit in place is a faulty one, I would say. Instead of the pivot being in a hole, it sits in half a hole (see photo 2) and it's kept in place by a spring.

As you might expect if you try to rotate this gear from certain angles it'll wiggle around, the pressure that you use might matter as well but not my much.

From what I see the minute and hour gears stop at some point and I feel like the problem is in this area, quite likely something to do with the wiggly gear. I feel like because it can have a bit of play, it'll just stop turning at some point due to pressure or something...

I could try and remove the minute and hour gears and clean them up of any lube or re-lube them but, as I said, the watch came with this problem (the 2 hands not moving).

I'm thinking that if the 3rd gear is encountering too much resistance from one or both of the minute and hour wheels then it'll just try to move away from the gears and stop rotating and since that little spring is a bit flexible this might make the whole thing stop running.

Part B is the bent tooth area. Feel free to offer your input.

And I wanted to ask if part/area C looks normal. There seems to be some sort of a cavity in the minute gear pinion or whatever you call it. I can't tell if it's factory made or broken but the edges seem straight.

Edited June 27, 2018 by Chopin

[Melt]

I would first check the movement without the hour wheel to eliminate the cannon pinion C that looks possibly damaged jamming on the hour wheel somehow. If it stops again I would remove the minute wheel A and see if the movement runs without stopping. Last thing to check would be is the cannon pinion too tight. Oh and maybe you need to lubricate the minute wheel A were it touches the spring

Edited June 27, 2018 by Melt

[Chopin]

Coming back with an update. I believe the problem is the canon pinion. There doesn't seem to be much friction between the 2 gears that make up the canon pinion ensemble. (one further clue is the fact that when I would set the time the hands would move way too fast/easy which as far as I know is what happens when a canon pinion is loose)

Decided to do all sorts of tests and strip/install various parts in turns and I came to the conclusion that when all the gears in the center are mounted the canon pinion just won't rotate (as if it's loose)... Also, with all the gears installed I would move the canon pinion myself and the gears turned fine.

Could someone tell me how I can tighten it a bit ? Does the small gear on top come out somehow ?

[Chopin]

Paging doctors @ecodec @anilv @vinn3 @Melt .

[anilv]

https://www.watchrepairtalk.com/topic/6604-tightening-a-cannon-pinion-on-wrist-and-offset-cannons-also/

[ecodec]

3 hours ago, Chopin said:

Paging doctors @ecodec @anilv @vinn3 @Melt .

Hi, I do not like the look of those gear teeth. However if you want to tighten the canon pinion there are several ways. Too protracted for me to go into here as the canon pinion has to be accurately set. However, you may be able to see a witness mark where it was originally set and if so then you could push an arbor thru it that is a slide fit so that it will not collapse and very carefully tighten it with a slight tap on the witness marks and then remove the arbor. Be very careful as the canon has to fit with just a little frictional contact over the centre wheel arbor in order to get the  required drive to the hands. I am very tired now so I hope that I have got this right. Mike.

[Folkvisor]

If you have a staking tool you can use it to tighten the canon pinion by resting it on one  wedge-shaped attachment while resting another like attachment against the top and then giving it a tap with a jeweller's hammer. It is best to limit the "crush" with a needle.

I know this works because I've done it but you need to be VERY careful and fit it after every tap. If you go too far it is almost impossible to undo your mistake.

But perhaps a wavy washer is not what you need here. Both a 2824-2 and a 2836-2 movement use a spacer ring around the outside of the movement instead of a wavy washer because the dial will bend if a wavy washer is used and this can stop both the date wheel and the hands from moving properly. I'd check to see if this is the case. From the look of your watch I think it may be.

[Chopin]

I managed to separate the 2 gears and apparently the shaft of the little one is cracked in 2 spots (someone may have tried to tighten it too much or something ?) opposing each other.

I'm not sure if it's going to work if I tighten it... Might have to find a replacement now. Watch problems are never easy for me. It always goes from bad to worse.

I also don't have a staking set, sadly.

Edited June 29, 2018 by Chopin

[Chopin]

Took a chance and tightened it. So far so good. Will reassemble the movement tomorrow. Wish me luck!

[Folkvisor]

If it still stops it may be that it needs a rim spacer instead of a wavy washer.

Good luck

[Chopin]

6 hours ago, Folkvisor said:

If it still stops it may be that it needs a rim spacer instead of a wavy washer.

Good luck

The movement already has one. It doesn't get inbetween the dial and movement but it does have a metallic ring that sits in that area (or covers it).

[Folkvisor]

O, ok. Well the dial bending isn't the problem then. It was a problem on a watch I was working on - mostly due to an inept watchmaker...me.

From how you describe the canon pinion it could well be the issue or there may be some slippage in the intermediate wheel that connects between the minute and hour wheel. This may have already been mentioned.

 

 

Edited June 30, 2018 by Folkvisor

[Chopin]

Hopefully the last update. So far it seems that it's running as it should so the canon pinion was, indeed, the problem.

Thanks guys!

[Folkvisor]

Good to hear!

[Folkvisor]

So, is it still working?