ETA Running Problem

[spiro13]

Hi

I have a ETA 2801-2 that runs reasonably well when it is on a full wind : Amplitude-232,  Beat error - 1.0, Rate- +10sec.  with the regulator in the central position. After appx. 15 hours the numbers are as follows: Amplitude-198, Beatt Error-2.5, Rate- +30sec. I would appreciate suggestions as to what might be the problem. I'm thinking maybe it is a Mainspring problem.

Thank you,

Tony

[Nucejoe]

I agree your own with your own diagnosis, your watch can use a new mainspring at service time.

Edited May 28, 2020 by Nucejoe
Reduce the beat error

[Chrono15]

  On 5/28/2020 at 6:37 PM, spiro13 said:

Hi

I have a ETA 2801-2 that runs reasonably well when it is on a full wind : Amplitude-232,  Beat error - 1.0, Rate- +10sec.  with the regulator in the central position. After appx. 15 hours the numbers are as follows: Amplitude-198, Beatt Error-2.5, Rate- +30sec. I would appreciate suggestions as to what might be the problem. I'm thinking maybe it is a Mainspring problem.

Thank you,

Tony

Expand  

Tony,

 

It likely just needs a service and new mainspring. That amplitude is on the lower side.

[watchweasol]

Got to agree with the others  the mainspring is nearing retirement.

[VWatchie]

I too agree with the others. A service, a new mainspring and regulating it would likely get your watch in perfect order. For a top notch modern movement like your ETA calibre 2801-2 the B.E. shouldn't be more than about 0.3 ms.

[clockboy]

I would service the movement and in doing so you can check the mainspring.

[spiro13]

Thank you for the comments.

Tony