Chronograph Pusher Rod for EB8371-67 Snapped and Stuck in Button. Can't Unscrew.

[HouseofGeorge]

Hi everyone!

Hope you're all keeping well. I'm working on an old Chronosport Chronograph with an Ebauches Bettlach (EB) 8371-67 and broke the lower pusher's rod and leaving the other half still screwed on to the button pusher. 

I was able to unscrew the upper button albeit with a little resistance perhaps glued by the previous watch repairer. However, for this lower one, the rod just wouldn't budge. I've soaked the button in Acetone in the hopes of melting the glue and it still wouldn't move. Blasted it hot with a hairdryer, touched it with a soldering iron and still no go.

As you can see on the photos below, the pusher is flat on one spot due to my holding it with a vise grip, yes, that's right. Vise grip. I was desperate see. Twisting and turning both the rod and button resulted in nothing. I did, however, successfully bent the rod. So, further trying to correct the bend the next day, I ended up snapping the whole thing in two.

So, I'm wondering what my options are and if someone can give guidance:

• Replace the rod. Where to get the replacement rod then how to remove the broken stump?
• If removing the stump, how and with what?
• Replace the whole set of pushers, ie the upper and lower buttons.
• If replacing, will generic parts do and where to acquire them.

Any advice or solution given is very much appreciated.

Thanks in advance.

Jesse

 

Chronosport c1970s

Pictures of the same button. Note the stump and flattened button.

This picture is the other pusher. Disassembled with no issues. Note the melted gasket.

[RichardHarris123]

I don't think that stems ( correct terminology? ) are available for pushers. You probably have to replace the whole pusher.  Pusher tubes  are either drive in or screwed. Can you post a photo of the inside of the case where the pushers connect? 

Edited April 21, 2024 by RichardHarris123

[HouseofGeorge]

6 hours ago, RichardHarris123 said:

I don't think that stems ( correct terminology? ) are available for pushers. You probably have to replace the whole pusher.  Pusher tubes  are either drive in or screwed. Can you post a photo of the inside of the case where the pushers connect? 

Thanks RichardHarris123 for your quick response. I've attchached close ups of the outside and inside of the case for closer inspection. Hope it helps.

Cheers.

Inside of the case

Close up of lower pusher tube

 

[watchweasol]

Hi are the pusher heads made of brass, if so you could soak the broken one on alum solution to dissolve the steel portion if all steel then it’s a no go and probably as @RichardHarris123said replace the whole pusher. Place to start it’s Cousins uk, material supplier.

one could also drill it out ,but that would need precision drilling not to damage the thread and the pusher.

[RichardHarris123]

I'm trying to decide whether or not the tubes are screwed or driven ( friction). Screwed usually have splines, yours doesn't but is that a  pin inside the tube? 

[watchweasol]

Hi   Looks like a pin. Looking at the removed pusher at a guess I would say I pushes up from th inside with the spring and the button is then fitted the pin acts as a stop, pure guess work.

[HouseofGeorge]

16 hours ago, watchweasol said:

Hi are the pusher heads made of brass, if so you could soak the broken one on alum solution to dissolve the steel portion if all steel then it’s a no go and probably as @RichardHarris123said replace the whole pusher. Place to start it’s Cousins uk, material supplier.

one could also drill it out ,but that would need precision drilling not to damage the thread and the pusher.

Hi wathweasol. I think it's made of brass. From the look of things, replacing the whole pusher as a set is beginning to be the way to go. Thanks.

13 hours ago, RichardHarris123 said:

I'm trying to decide whether or not the tubes are screwed or driven ( friction). Screwed usually have splines, yours doesn't but is that a  pin inside the tube? 

I'm thinking it could be just a tube and friction fit. I've taken another shot of the tube and posted here. Looks like just a tube fitted flush. Then, again, I have no experience in chronographs especially tubes and pushers.

12 hours ago, watchweasol said:

Hi   Looks like a pin. Looking at the removed pusher at a guess I would say I pushes up from th inside with the spring and the button is then fitted the pin acts as a stop, pure guess work.

This one has no clips or washers to lock in the pusher in place. Coming from the outside, you'll have the button, spring and the stem inserted from the case and screwed in. The case holds the spring in place and the ridge at the other end of the stem keeps it from falling out of the case.

Posted some pics here and an illustration to help.

My sketch of how all the parts come in to play:

Two different angles of the stem. Note the ridge near the slotted end that stops it falling out.

This is an assembled piece of the one that was successfully pulled out.

If it will have to be replaced, may I have some tips please on how to place an order, sizing, etc (Cousins, Esslinger,...) and on how to remove/install the pushers. My experience is just basic service with time only, day/date complications. Haven't had the opportunity to replace crown tubes and pushers.

Thank you so much.

[RichardHarris123]

I think it is friction fit, there are tools to remove them, cheaper versions are available. You could try adapting some pliers, see my crap drawing.  The pushers are available in various sizes, you could measure once the tube is removed. 

[watchweasol]

Hi. Yes I get it , the slot in the end I’d to allow you to screw the button on whilst holding the pusher shaft. To remove the pusher tube you will need a tool such as the one shown by Richard. I think Ali Express the Chinese Amazon has replicas of the Horotec system for a lot less money, how effective they are not having had to use one. But as you said the way to go is complete removal and replacement, bodging it up will  lead to a repeat failure

[HouseofGeorge]

15 hours ago, RichardHarris123 said:

I think it is friction fit, there are tools to remove them, cheaper versions are available. You could try adapting some pliers, see my crap drawing.  The pushers are available in various sizes, you could measure once the tube is removed. 

Thanks for the screenshots. That's very helpful even the drawing which resembles a Bergeon 6160 so I know what you're saying.

Most probably I'll get the horotec clone from Ali-x.

15 hours ago, watchweasol said:

Hi. Yes I get it , the slot in the end I’d to allow you to screw the button on whilst holding the pusher shaft. To remove the pusher tube you will need a tool such as the one shown by Richard. I think Ali Express the Chinese Amazon has replicas of the Horotec system for a lot less money, how effective they are not having had to use one. But as you said the way to go is complete removal and replacement, bodging it up will  lead to a repeat failure

Yes, looks like time to go shopping for the tool. Alix for the removing took and Cousins for the pushers. They do come with the gasket in-built yeah? I guess I'll find out.

Thanks guys for your input. Keep up the horology work! 

[rjenkinsgb]

Look carefully at the tube end?? It appears to me to have a fragment thread visible?

Either that or a step just away from the end? I can imagine a chamfer, but a step seems odd - but I've never seen the tubes used on these.

[HouseofGeorge]

4 hours ago, rjenkinsgb said:

Look carefully at the tube end?? It appears to me to have a fragment thread visible?

Either that or a step just away from the end? I can imagine a chamfer, but a step seems odd - but I've never seen the tubes used on these.

Thanks for the tip. I'll have another look just to be safe. But, shouldn't there be like a splined or geared end to unscrew the tube? This one is just straight tubing.

On 4/23/2024 at 5:29 PM, RichardHarris123 said:

I think it is friction fit, there are tools to remove them, cheaper versions are available. You could try adapting some pliers, see my crap drawing.  The pushers are available in various sizes, you could measure once the tube is removed. 

So, I tried contacting Cousins UK asking if these pushers come with the tube or not and unfortunately they couldn't help and their website has no documentation if it does come with tubing.

That said, do they come in complete, ie tube, gasket, pushers? I'm not sure which of these two would be more appropriate:

Thank you.

[RichardHarris123]

Which is closest to the ones you have? 

[HouseofGeorge]

2 hours ago, RichardHarris123 said:

Which is closest to the ones you have? 

I would say this one:

 

[RichardHarris123]

Take the measurements and go for which ever on you like. An assortment us under £11.