Marinemaster servicing

[Mountain]

Hi all,

I’ve been wearing my Marinemaster 300 recently, but it seems to be gaining about a minute and a half a week.

It has the 8L35 movement and the monocoque case, so the movement is only accessible for regulating through the crystal.

My question relates to ease of service: Is this a job any competent watchmaker should be able to do, or does it need to be sent back to Seiko?

Thanks very much in advance!

[JeremyS]

If by a week you mean 7 days, that’s just shy of 13 seconds per day. Seiko’s claimed accuracy for the non-adjusted 8L35 is +15 to -10 seconds per day. So, by Seiko standards it’s within spec. However, if this watch is due for a service anyway, I’d just send it to Seiko and have the complete service done.

I suspect any watchmaker could adjust the accuracy, as the movement has a screw-regulator. However, opening and re-sealing the case might be difficult.

[Mountain]

Thanks, appreciate the comments. I realise it’s within spec, but I’m equally aware this movement is capable of so much more! It’s a shame Seiko don’t regulate their movements to their full capability.