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Power réserve - looking for infos


davidrrd

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Hello Guys,

Some time ago a friend of mine told about his watch that he wasn't wearing much because he felt it wasn't keeping charge as expected. A Maurice Lacroix with a 2836 mouvement (Élaboré or Top, not sure) that would stop within a day after been wear. He changes for an Apple watch for work reasons. I used it for bit to see how it behaves and on regular use it was Ok (as I can say with my short experience).

 

Being an expensive watch and because of my little experience I didn't feel like servicing it myself, to much of a risk. So I advice him to take in for service (apparently he had it for ten years without one... So it couldn't be harmful) We used a workshop where I repaired a vintage Omega before. Everything went as expected and the watch seemed to work as expected afterwards. However he told in the last couple of days that it is behaving as before - stoping apparently within a period of 24h.

 

Well I cannot say I have seen it myself so.... But as I am learning I come to you for information. As I understand the problem might come from the mainspring - insufficiently cleaned/oiled, maybe one that need to be changed?. Second supposition the watch is not charging as intended while being wear. But what may cause that? Would not attack it myself .... But I would.like to help my friend to point the possible problem to the workshop.

 

Thanks in advance for all your help.

 

David 95b6d620f03f5bfd62a71a37c1a871d6.jpg796f68a13759a8fb32aa94a632d4c9df.jpg

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In my limited experience power reserve problems are usually mainspring related. When it was serviced, the mainspring should have been replaced. If it was and it's still exhibiting this problem, I would suspect an issue with the automatic winding mechanism.

Does it exhibit the same problem if it's manually fully wound and then left alone?

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Hi,    Parts for eta2836 are available. So strip down and service is not too risky.

Manually wind full, observe if it runs longer. How long it runs tells you how strong the mainspring is also tells you if the winder is weak.

Good chance you may need to change rotor bearing or just the balls of the bearing.

Otherwise good thoroug cleaning and use of proper oil and grease seems to be all you should be concerned with.

Pix at all stages of strip down and parts may come useful in case unexpecfed faults exist.

Regards joe.

 

 

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Thanks guys for the infos. I am currently servicing a 2834 that I got for around 25 bucks in a flea market. I can source parts so I feel.more confident now.... However that watch is a 2000 dollars one....(more expensive one I have might be 120) ... And being an Élaboré or top movement I didn't want to take the risk.

Out of curiosity. During a service they systematically change the mainspring?
Gonna see the updates and will let you know. As for now..... I think it maybe a problem with a weak automatic mechanism.
I've seen sources for the bearing of the rotor..... May I ask you on how to change it?
Thanks again.

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Some useful sites in case you havn,t visited so far.

Julesborel.com

Eternaltools.com

OldSwissWatches.com

Most recommended source is cousinesuk.

Yes manufacturers recommend routine M/S replacement. Manual winding gives you an idea how well the spring feels, to say the least eliminates selfwinding mech form diagnostic guestimation.

Joe

 

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Some useful sites in case you havn,t visited so far.
Julesborel.com
Eternaltools.com
OldSwissWatches.com
Most recommended source is cousinesuk.
Yes manufacturers recommend routine M/S replacement. Manual winding gives you an idea how well the spring feels, to say the least eliminates selfwinding mech form diagnostic guestimation.
Joe
 
Thanks a lot Joe for the information.
I've come by those websites once in a while but I keep forgetting to go back and check for infos. I need to bookmark them. Sometimes the problem is also knowing what I am looking for (lol) .... Still a beginner.
Anyway.... I think they will come in handy with my latest project a 2834 I am trying to save..... Followed the technical sheet, I learned a lot but I have some trouble with the Quickset feature, the keyless work and the power reserve. However is running beautiffully when worn. I think the movement was a bit abused and some parts are a bit tired. Will start all over again after looking for the parts I think are faulting.
(With my impatience it is a bit upsetting, but I know it is a good practice and learning process)
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Hi. Back again with my questions. @Nucejoe. I checked the websites and yes I know they are good sources for parts. However living currently in China makes deliveries a bit complicated. Will see.
As for my questions..... I am currently checking the behaviour of the 2834 after service. When worn it runs fine.... But when I put it back in the shelf it stops after a couple of hours. I manual wound it to check and it has been running for more than 30 hours sitting on a shelf dial up. So it tells me that mainspring is keeping energy....
So the problem might come from the automatic mechanism. I tried to check it and it seems to engage the ratchet wheel as expected so I do not know where the problem might come from. Can it be the rotor bearing or maybe the reduction wheels that are just tired and need a change? How can I estimate the probable cause to buy the right parts.... Without buying all'of them!
Thanks for the help!

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Hi David,  Did you see the video johnR provided the link to, showing the thirty seconds test for Eta rotor bearing?  Kinda proved invalidity of my test, I use to think if the winder winds falling under own weight, it is doing its job. The new question is, How well the performance is? How long it winds ?  Surely you agree, apart from bearing, is the winder module and the auto power transfer to the MS and not just parts which are to be  in good working condition but type of lubricant plays an important role, how viscus is the oil?

I encountered as case of barrel lid barely rubbing on barrel bridge, the movement Run for a couple hours and came to stop as friction got to max. So we just got to look for the fault till found. 

Regards joe

 

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Hi Joe. Thanks for your answer. I haven't see that video and it seems I cannot find the link. What thread did he posted it in?
And thanks for sharing your experiences as well. That's the kind of issues I would not expect..... As soon as I finish moving to my new place I will work on it I am looking forward to see it working fine.
As for the oils I followed the procedure described in the 2836 technical sheet from ETA and Mark's video for the 2824 mvt. I am using Molykote DX, Moebius HP1300, 9415 and 8000
(On an old moebius chart I found the 8000 was cited along the 9010) I recently bought the HP1300 and 9415 but tried to keep the facture controlled. The 8000 I bought it when I first started and I moving slowly to a more serious approach. So for the automatic module I used HP1300 (D5) for the transfer wheel and the 8000 for the jewels of the reverse wheels and the reduction wheel. Note that I did not clean the Reverse wheels as advice.... So maybe the oil inside is not doing a proper job either.

Anyway. I keep on looking....just know I keep checking the reserve after a 60tour manual wind.

PS. Let some photos of the beast! Before and after. I'd did not buy because I liked it the look but mostly for the movement. So I modded it and will have more changes in the future. bef0b63817579cf6f10fd2bf8136fcf6.jpgfaaf72fb63220ee687086f5fa601685f.jpgad31ec44b7ded27a3038430e85dcaba1.jpg9b2778702cce30224f1ce73e882d1f62.jpgb10c79fd772b577b71b5e9cb2da74975.jpg

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