Description
Overview:
This genuine Stihl decompression valve is a small, threaded engine component that screws into the cylinder head to momentarily lower compression during starting. Built with a durable metal body (silver finish), a hex head for easy tightening, and a sealing O-ring, it is designed for reliable service in demanding use. By reducing cylinder pressure at pull-start, it lessens the effort required to start the engine and helps protect the recoil starter. Suitable for Stihl brushcutters and clearing saws, including FS 400 and FS 450, it measures 40 mm (1.57 inches) in overall length for a neat fit. Ideal for routine maintenance or replacing a worn valve to restore easy starting and consistent performance.
Key Features:
- Genuine Stihl part for correct fit and function
- Reduces cylinder compression to make pull-starting easier
- Helps minimise strain on starter rope and recoil mechanism
- Robust metal construction with hex head for straightforward fitting
- Integrated sealing O-ring for reliable, gas-tight seating
- Length 40 mm (1.57 inches) for compatibility with specified models
- Suitable for heavy-duty, professional, and domestic use
- A practical preventative-maintenance replacement to maintain starting performance
Typical Applications:
Used on Stihl brushcutters, clearing saws, and similar two-stroke equipment to ease cold and warm starts, especially on high-compression engines. Ideal when a machine has become hard to start, the starter rope is experiencing increased wear, or after engine service work. Suitable for daily use by landscapers, grounds maintenance teams, arborists, and informed DIY users who want dependable starting and reduced pull effort.
Also known as:
Compression release valve, pressure relief valve, start-assist valve, cylinder bleed valve, decompressor.
Fits Models:
FS 400
FS 450
FS 480
FR 350
FR 450
FR 480
FR 480 C
SP 400
SP 450
SP 451
SP 481
Alternate Part Numbers:
4128-020-9400, 41280209400
Product Specifications
| L&S Part No. | 4128 020 9400 |
|---|---|
| Part Type | Genuine Part |
| Manufacturer | Stihl |
| OEM No. | 41280209400 |
| Unit of Sale | 1 |
| Size | Length of Valve: 40mm |
| Machine Type | Brushcutters, Trimmers |
| Fits Brands | Stihl |
| Key Features | - Genuine Stihl part ensures correct fit and function - Reduces cylinder compression for easier pull-starting - Hex head design allows straightforward fitting - Integrated O-ring ensures gas-tight seating - Compatible with FS 400, FS 450, FS 480 models |
| Fits Models | FS400, FS450, FS480 | FR350, FR450, FR480, FR480C | SP 481 |
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