Seiko Cal. 4M21A Parts Catalogue and Technical Guide
Complete parts catalogue and technical guide for the Seiko Cal. 4M21A automatic watch movement. This workshop manual provides detailed component specifications, part number identification, and exploded diagrams essential for service and repair work. Coverage includes the oscillating weight assembly, capacitor unit, circuit block, generating rotor, train wheel set, and setting mechanism. Technical sections address lubrication requirements, resistance measurements, current consumption data, and procedures for checking the automatic generating system. Ideal for watchmakers performing maintenance or rebuilding operations on this movement.
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Document Details
- Format
- Pages
- 13
- Size
- 408.2 KB
- Category
- Watchmaking