John from East Coast U.S. and eBay 7s26A (genuine movement?)

[LeftHandThread]

Hello everyone, 

I'm a novice in watch repair excited to have resources like this forum available to me! The idea of watch repair all started when I dropped my Seiko SKX009 and realized it was no longer keeping acceptable time. I have tinkered with machines all my life and just received my BS in mechanical engineering, so naturally I wanted to know how everything in my watch worked. I started researching about watches and eventually came to the conclusion that the balance staff pivots are likely broken, but in either cases I could see the balance wheel wobbling.

Fast forward to now, I ordered a Seiko 7s26A movement from eBay and want to replace the broken 7s26B with the 7s26A, and the 7s26B can become a practice movement for me. My issue now is that the movement from ebay looks mostly legit, but has a sign that it may be fake or using some non genuine parts. Anyone have experience with the legitimacy of eBay stand alone movements?

The issue is with the lower plate. It seems that all pictures online show the words "SEIKO" on the lower plate next to and below the balance wheel. My movement does not have the words SEIKO on the lower plate at all. It is also a twenty year old movement which raises concerns on the oil and grease, the eBay seller said that they sonically cleaned it and oiled it though.

Thanks everyone,

John

[LeftHandThread]

Note, the rotor does have the inscribing on it, the picture just has glare the and the writing did not show up. The rest of the movement seems identical aside from the lower plate.

[Nucejoe]

Hi John, Welcome to the forum.

 I would bench time the watch in face down FD and face up FU positions. Top and side view close ups of balance assembly helps.

 

[JohnD]

Welcome, as an aside, if I was replacing the movement in a SKX007 I'd swap a new NH36 in instead of an old 7s26. Apart from the advantage of the reliability of a brand new movement you get the bonus of hand winding, on top of the auto and hacking. What's not to love for about $30?

[LeftHandThread]

Thank you for the greetings!

my watch was gaining around 2 min a day when I set it then waited 24 hours so something is definitely wrong or broken.

JohnD,

I did think about that, but kind of wanted the 7s26 to keep things original. I thought it would be cool to keep the non hand winding and hacking although it isn't the most convenient haha! If I do a modded skx then the NH36 definitely something to consider.

[jdm]

1 hour ago, LeftHandThread said:

Te issue is with the lower plate. It that all pictures online show the words "SEIKO" on the lower plate next to and below the balance wheel. My movement does not have the words SEIKO on the lower plate at all.

That is absolutely normal, Seiko has produce this movement over many decades and in various factories in Asia, variations in finishing and lettering are expected. 

The advice to replace with a brand new NH36 was also a good one, then of course anyone does as he pleases.