Caliber 3130 weird behavior

[tom1969]

Hello,

I'm having trouble with my recently acquired Explorer 114270 from 2008. As I have a one-year warranty I'm obviously going to have to take it back to the dealer, but before I do that I want to wisen up a little on what might be going on.

It looks as if this mint-condition watch had been sitting in a drawer for most of its life. When I got it in mid-February it was gaining about 4 seconds per day when lying dial-up at night and 3 s/d crown-down. So I kept it crown-down until after three weeks all of a sudden it gained over 30 s/d. During the day it still gained 4s/d, only to make a huge 25-second leap overnight.

When i reverted back to keeping it face-up at night, it went back to its original 4s/d.

Here's my theory: When being worn after the long storage, body temperature and movement mobilized a droplet of lubricant that had collected over the years, which then made it onto the hairspring. With the hairspring horizontal (dial up), the oil is distributed evenly on the string and doesn't cause any harm. When the hairspring is vertical, the droplet collects in the lower part of a spring loop, causing it to stick and make the watch run fast.

Plausible?

The watch came with the original warranty card but without any service records, so I assume that it hadn't been serviced recently, if ever.

For some reason I don't understand, watchmakers are not on the list of "essential" businesses during Corona times, so in lieu of dealing with this I'm just theorizing here.