Watch gains 2mins then no more

[Beachbum]

So a bit of a strange one, or at least strange in my eyes
Marathon CSAR, so using 7750 internals. Gains 2mins in the first week to 10 days, then gains no more.
Anyone have an explanation on this one ?
It is not a one of, have reset the watch the last 3 months and the same thing has happened every time.

[Ikemi]

Magnetised, possibly? Movement may need de-magnetising in order to sort out your accuracy issues!

[Mr_C]

Set it 2 minutes slow to start with and in ten days it'll be right.

[hornetrider]

Mr_C said:

Set it 2 minutes slow to start with and in ten days it'll be right.

/thread

[bobbybee]

I don't have an answer, but I used to have a Sub-Date like that.
Used to check it once a month, always 2 mins fast, set it 2 mins slow on purpose, end of the month........... 2mins fast.
But it never deviated from that, very strange.

[Variomatic]

Beachbum said:

So a bit of a strange one, or at least strange in my eyes
Marathon CSAR, so using 7750 internals. Gains 2mins in the first week to 10 days, then gains no more.
Anyone have an explanation on this one ?
It is not a one of, have reset the watch the last 3 months and the same thing has happened every time.

I assume you mean the first week - 10 days from being stopped? If so, do you manually wind it (fully) to get it started or give it a shake / couple of winds and rely on the auto wind to do the rest?

It can quite easily take an auto a week to build up full reserve power unless you're very active with it, and watches tend to run fast when they have low power. I don't have the 7750 specs to hand (I've been banned from bringing things like that home with me ) but you can quite easily get a 10 - 20 sec / day difference in rate between fully wound - where an auto will normally run - and fully unwound - where yours may be starting from.

A simple test to see if that's the issue is to let it stop, then wind it fully by hand. Being an auto, it won't give any obvious indication that it's fully wound so give it 30 - 40 good turns of the crown. You won't hurt it doing that once in a while.

If, after doing that, it runs to tome from day one then that's your cause. If it still gains 2 minutes before settling down to time then it probably need an exorcism because there aren't any other likely technical reasons for it.

Yeti will be along shortly to suggest sending it to the makers paranormal dept, but you'd be just as well using any local vicar.

[PJ S]

Variomatic said:

Yeti will be along shortly to suggest sending it to the makers paranormal dept, but you'd be just as well using any local vicar.

DIY – say the Lord's prayer backwards whilst dunking the watch in some de-ionised water (holy water will do if you've no Halfords local to you) at a rate of not more than 5 dunks per word.

[sparkyhx]

bobbybee said:

I don't have an answer, but I used to have a Sub-Date like that.
Used to check it once a month, always 2 mins fast, set it 2 mins slow on purpose, end of the month........... 2mins fast.
But it never deviated from that, very strange.

definitely ghosts

[Variomatic]

PJ S said:

DIY – say the Lord's prayer backwards whilst dunking the watch in some de-ionised water (holy water will do if you've no Halfords local to you) at a rate of not more than 5 dunks per word.

That should work fine, but please don't use cheap Chinese holy water - it has a nasty habit of causing corrosion!