Description
Overview:
The Starter Boss for JAP Model 4/3, 444H-2 Industrial Engine is a genuine JAP component designed to mesh with the engine's manual starting mechanism and transmit torque reliably. Built from durable metal for long service life, it serves as the primary hub that engages with the starting handle or ratchet assembly to crank the engine. This part is made to OEM specification for a correct fit and alignment on JAP industrial engines, including the 4/3 and 444H-2 models. As unused old stock, it may show light tarnish or surface marks from age, but remains functionally sound. Use it to restore dependable starting performance on vintage and working engines, ensuring correct engagement and reduced wear across the starting system.
Key Features:
- Genuine JAP part for assured compatibility and correct fitment
- Durable metal construction designed to handle repeated starting loads
- OEM-equivalent geometry for positive engagement with the starting drive
- Helps restore reliable manual starting on vintage industrial engines
- Direct replacement for OEM reference 21751/1
- Suitable for workshop refurbishment or ongoing maintenance of legacy machinery
- Unused old stock: functionally new, with possible cosmetic ageing only
- Straightforward swap for a worn or damaged original component
Typical Applications:
Used on JAP industrial engines fitted to site equipment and stationary plant such as generators, pumps, mixers, compactors, and agricultural or horticultural machinery. Ideal for rebuilds, restorations, and maintenance where a precise, robust starting interface is needed to ensure consistent hand-start operation in workshop and onsite environments.
Also known as:
Starter hub, starting boss, starting handle boss, starter drive boss, crank boss, starter coupling. Often identified by the OEM reference 21751/1 within JAP parts catalogues for vintage industrial engines.
Fits Models:
4/3, 43, 444H-2, 444H2, JAP 4, JAP4
Alternate Part Numbers:
21751/1
Product Specifications
| L&S Part No. | 21751/1 |
|---|---|
| Part Type | Genuine Part |
| Manufacturer | JAP |
| OEM No. | 21751/1 |
| Unit of Sale | 1 |
| Machine Type | Engines |
| Fits Brands | JAP |
| Key Features | - Genuine JAP part ensures compatibility with JAP engines - Durable metal construction for repeated starting loads - OEM-equivalent geometry for precise engagement - Direct replacement for OEM reference 21751/1 - Suitable for JAP models 4/3 and 444H-2 |
| Fits Models | JAP 4, 3 |
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