[Thinktank15]

Hi all,
So I recently purchased a brand-new Seiko SBBN035 with the 7C46 quartz movement. I noticed something quite odd when setting the time. After positioning the hands to where I want them, if the crown slightly rotates while I'm pushing it in, the seconds hand (yes, the seconds hand) of the watch jumps by 30 to 40 seconds, stays there for a second, and then begins to run as normal. For example, if I have the watch stopped with the seconds hand at 12:00, and if I rotate the crown while pushing it in, the seconds hand will ping ahead 30-40 seconds. The watch keeps perfect time, but this struck me as being very odd, since my solar Tuna doesn't do this. Is this a common thing with quartz watches, or with the 7C46? Has anyone else experienced this? Thank you for your help!

 

[dak_la]

My SBBN035 doesn't do that, the behavior you described is odd but I would say there is something wrong.

 

[Somewhere Far Beyond]

Something seems off for sure. My SBBN037 does not do this, nor does any other watch I own or have owned, quartz or otherwise.

Sent from my moto x4 using Tapatalk

 

[Thinktank15]

Well, I tried to replicate the issue just now. It seems I have to deliberately try to turn the crown clockwise while pushing it in to get the seconds hand to jump, so it doesn't really hinder normal time-setting or anything. It doesn't happen if I push the crown in normally. It's just something I've never seen on a quartz before, Seiko or otherwise. I don't suppose it would cause any damage to the movement, would it?

 

[JacobC]

Most Seiko quartz movements jump in larger and larger increments as the battery depletes. You need a new battery.

 

[Thinktank15]

The watch runs fine. The second hand jumps right after I push the crown in. Also, I just received the watch today, brand-new, and it was manufactured in January 2020, so I doubt there'd be any battery issues for a while yet. Thanks for your reply, though.

 

[Trog7074]

Return it.

 

[sticky]

Neither of my Tunas do that so send it back.

 

[kokoro]

Return it .

 

[saloei]

Sounds as if the movement is keeping track of time though you have the crown pulled. One way to test this is to set the time but make sure it takes you only ten seconds to set the time. See if when you push the crown back it'll only jump 10 seconds.

 

[SamRHughes]

It sounds like there is some hacking mechanism engaged on the gear train leading from the seconds hand to the motor, to prevent the seconds hand from moving, which is getting released before the setting mechanism connecting the step to the gear train gets disengaged.

 

[Ginseng108]

Sounds as if the movement is keeping track of time though you have the crown pulled. One way to test this is to set the time but make sure it takes you only ten seconds to set the time. See if when you push the crown back it'll only jump 10 seconds.

I believe this is fundamentally incorrect. The movement is nothing more than the motor on anything other than a perpetual calendar. The hands and date wheel are the timekeeping displays. There is not a mechanism inside a standard 3-hander that has anything approaching a "memory."