Seiko 2626B – Technical Guide (High Quality)

The Seiko 2626B is an updated version of the Seiko 2626A quartz movement, specifically engineered for ladies’ wristwatches in the early to mid-1980s. Like its predecessor, it offers three-hand functionality (hour, minute, and central seconds) with a day-date complication, all housed within an ultra-compact and reliable quartz platform. The “B” variant reflects minor technical improvements, especially in circuit layout, calendar alignment, and energy efficiency.

1. Technical Specifications

2. Key Features

• Full calendar: Displays both day and date at 3 o’clock

• Bilingual day wheel: Common combinations include English/Spanish or English/Kanji

• Quickset date: Fast adjustment via crown at first position

• Day changes via hand cycling (not quickset)

• Hacking function: Second hand stops for accurate time setting

• Improved IC layout and efficiency vs. 2626A

• Compact dimensions for slim, elegant ladies’ watches

• Durable and low-maintenance movement structure

3. Calendar Operation

How to Set the Time and Date:

• Crown Position 0 (pushed in): Normal operation

• Crown Position 1 (first click):

  • Turn clockwise to quickset the date

• Crown Position 2 (fully pulled out):

  • Set the time by rotating hands

  • Advancing hands past midnight changes both day and date

  • Second hand stops for precise setting

⚠️ Important: Avoid quicksetting the date between 9 PM and 2 AM, when the calendar mechanism is engaged.

4. Movement Design and Architecture

Dial Side:

• Day and date wheels mounted concentrically

• Calendar jumper, driving finger, and quickset gear

• Hour, minute, and second wheel train

• Cannon pinion, clutch wheel, and sliding pinion

Circuit Side:

• Quartz crystal (32,768 Hz)

• IC (integrated circuit) managing timing and motor impulses

• Step motor and rotor driving the motion works

• Battery contact springs, terminals, and insulation frame

2626B vs. 2626A:

• Better coil insulation and contact pressure

• Slightly refined gear tolerances for smoother hand motion

• Increased resistance to moisture and static discharge

5. Battery and Power

Battery Replacement Procedure:

1. Open the case back using appropriate tools

2. Remove the old battery using plastic tweezers

3. Clean contacts if oxidized

4. Insert new battery with positive (+) side facing up

5. Wait 10–15 seconds to observe second-hand movement

6. Reset time and calendar, then close case securely (replace gasket if needed)

⚠️ Handle components with ESD-safe tools to avoid circuit damage.

6. Common Issues & Solutions

7. Applications

The 2626B was widely used in Seiko ladies’ watches from the early to mid-1980s. Common characteristics of these models:

• Slim stainless steel or gold-plated cases

• Small case diameter (18–24 mm)

• Day-date window at 3 o’clock

• Domed acrylic or flat mineral glass crystals

• Case references such as:

  • 2626-7000

  • 2626-0030

  • 2626-5000

These watches were elegant, practical, and reliable for daily wear.

8. Service & Maintenance Tips

• Do not lubricate plastic components or calendar gears

• Replace case and stem gaskets during battery service

• Clean under-dial calendar parts with pegwood or blower, not oil

• Verify hand clearance before final assembly

• Avoid applying excess pressure to the day/date driving finger

Download

If you don't see the PDF file click on this link »