SEIKO (SII) NH36/NH38 Hour Wheel #0273183

Product Description

The SEIKO (SII) NH36/NH38 Hour Wheel (#0273183) is a genuine Japanese-made component for these popular automatic movements. As a core part of the motion work, the hour wheel drives the hour hand for accurate time display, working in conjunction with the minute wheel and cannon pinion. This brand new original part is essential for watchmakers restoring proper timekeeping function when the original component becomes worn or damaged.

Features & Function

• Genuine Seiko/SII part – authentic Japanese-made component for NH36 and NH38 movements

• Motion work component – drives the hour hand for accurate time display

• NH family compatibility – fits both day-date (NH36) and no-date (NH38) variants

• Direct replacement – drop-in replacement for worn or damaged hour wheels

Specifications

• Part Number: 0273183

• Compatible Movements: Seiko NH36, NH38 (also known as 4R36/4R38)

• Movement Family: NH Series (Basic Mechanical Series)

• Movement Diameter: 27.4 mm 

• Movement Height: 5.32 mm 

• Jewels: 24 

• Frequency: 21,600 vph (3 Hz) 

• Power Reserve: >41 hours 

• Accuracy: -20 to +40 seconds/day (factory spec) 

• Hacking: Yes 

• Hand-Winding: Yes 

• Origin: Japan

Applications

• Service and overhaul – replacing worn or damaged hour wheels in NH36/NH38 movements

• Motion work restoration – ensuring smooth and accurate hand alignment

• Suitable for professional watchmakers and experienced repair technicians

FAQs

1. Is this a genuine Seiko/SII part?

Yes, this is a genuine Seiko (SII/TMI) factory part made in Japan. The NH series is manufactured by Seiko Instruments Inc. (SII) and distributed by Time Module Inc. (TMI), with the NH prefix indicating unbranded sale for third-party watch manufacturers and the mod community .

2. Which movements is this hour wheel compatible with?

This hour wheel is compatible with Seiko NH36 and NH38 movements. The NH36 features day and date complications, while the NH38 is a no-date open-heart version . Both share the same motion work architecture, so the hour wheel is interchangeable between these calibers.

3. What are the signs that the hour wheel needs replacement?

Common signs include hour hand not advancing correctly, misalignment between hour and minute hands, or visible wear/damage during inspection. A qualified watchmaker can diagnose these issues.

Why Choose SOFLY Watch Parts?

• Fast worldwide shipping within 3 business days.

• Competitive pricing on Seiko/Hattori calibers.

• 3,000+ watch movements and parts in stock.

• Trusted by watchmakers worldwide.

• Personalized sourcing support via [email protected] or WhatsApp +86 18620212114.