Description
Overview:
This Piston Ring Set +020 is a genuine JAP component for vintage Villiers/J.A.P. engines, sized to suit oversize bores by +0.020 inch (+0.50 mm). It restores correct sealing between piston and cylinder, helping to recover compression, reduce blow-by, and improve starting and running quality on classic stationary machinery. Supplied as unused old stock, it is suitable for restorers and maintainers who need period-correct parts for JAP 3 and JAP 4 engines. The precision-ground metal rings are made for durability and stable operation under heat and load, supporting smooth performance when paired with a sound bore and piston. As an authentic part, it offers reliable fitment and specification consistency for heritage engines.
Key Features:
- Genuine JAP part for authenticity and correct fit on vintage engines
- +0.020 inch (+0.50 mm) oversize to suit rebored cylinders
- Unused old stock (NOS) with original specification
- Precision-ground ring faces for stable compression and oil control
- Aids easier starting and steadier idle on well-maintained engines
- Helps reduce blow-by and exhaust smoke when fitted to a suitable bore
- Compatible with JAP 3 and JAP 4 engines widely used in classic machinery
- Robust metal construction designed for heat and wear resistance
- Supplied as a matched set for consistent ring gap and tension
- May show light tarnish from age, with no effect on service function
Typical Applications:
Used during engine rebuilds or top-end refreshes on vintage JAP stationary engines powering mixers, pumps, generators, compressors, mowers, and similar equipment. Ideal when a rebore has been carried out to +0.020 inch (+0.50 mm) and a correct oversize ring set is required to restore compression and reliability. Suitable for preservation, restoration, or routine overhaul work.
Also known as:
Piston ring set, engine piston rings, oversize rings, +20 thou rings, compression rings set, ring pack, cylinder rings, JAP 3/4 ring set, vintage engine rings, NOS piston rings.
Fits Models:
JAP 3, JAP 4
Alternate Part Numbers:
JAP43RS20
Product Specifications
| L&S Part No. | JAP43RS20 |
|---|---|
| Part Type | Genuine Part |
| Manufacturer | JAP |
| OEM No. | JAP43RS20 |
| Unit of Sale | 1 |
| Applications | JAP 3, JAP 4, JAP3, JAP4 |
| Machine Type | Engines |
| Fits Brands | Villiers |
| Fits Models | JAP 4, 3 |
