Description
Overview:
This Decompression Valve is a genuine Husqvarna service part (part number 503 66 56 01) for professional cut-off saws. Built with a tough metal body and a durable blue cap, it screws into the cylinder and momentarily lowers combustion pressure during starting. That makes the pull start easier and reduces strain on the starter mechanism and operator. Designed for heavy-duty site conditions, it is suitable for petrol-powered construction saws such as the K950 and K1250, and a wide range of related models. The valve restores easy starting, supports consistent idling, and helps maintain overall engine efficiency, especially on well-used machines exposed to heat, dust, and vibration. A direct-fit, OEM solution for reliable performance and long service life.
Key Features:
- Genuine Husqvarna part for assured fit and reliability
- OEM reference 503 66 56 01 for accurate identification
- Robust metal construction resists heat, fuel, and vibration
- Blue cap for quick identification during servicing
- Lowers cylinder compression during cranking for easier starts
- Reduces stress on starter cord, recoil housing, and pawls
- Positive sealing when closed to maintain full operating compression
- Screw-in design allows quick replacement with basic tools
- Suited to intensive, daily site use in harsh environments
- Compatible across many Husqvarna/Partner cutters and 3120-series machines
Typical Applications:
Used on construction and rescue saws to make cold, hot, or repeated starts easier during concrete, masonry, asphalt, steel, and rail cutting. Ideal for equipment that sees frequent stop-start cycles, high load, or dusty conditions. Commonly replaced when the valve leaks, sticks, or the starter effort has increased, restoring dependable starting and reducing operator fatigue on site.
Also known as:
Decompressor, decomp valve, starting aid valve, cylinder pressure relief valve, pressure bleed valve, manual decompression button. These terms describe the same function: releasing some combustion pressure during cranking to make pull starting smoother and more consistent.
Fits Models:
3120, 3120K, 3120XP, 3122K, K950, K950 Chain, K950 Rescue, K950 Ring, K960, K960 Chain, K960 Rescue, K960 Ring, K970, K970 Chain, K970 Ring, K1250, K1250 Active, K1250 Rail, K1260, K1260 Rail
Product Specifications
| L&S Part No. | 503 66 56 01 |
|---|---|
| Part Type | Genuine Part |
| Manufacturer | Husqvarna |
| OEM No. | 503665601 |
| Unit of Sale | 1 |
| Applications | 3120, 3120K, 3120XP, 3122K, K1250, K1250 Active, K1250 Rail, K1250Active, K1250Rail, K1260, K1260 Rail, K1260Rail, K950, K950 Chain, K950 Rescue, K950 Ring, K950Chain, K960, K960 Chain, K960 Rescue, K960 Ring, K960Chain, K960Rescue, K960Ring, K970, K970 Chain, K970 Ring, K970Chain, K970Ring |
| Machine Type | Disc Cutters |
| Fits Brands | Husqvarna |
| Fits Models | K950 | K1250 | K1260 | K970 | 3122K | K1250 Active | K1250 Rail | K1260 Rail | K950 Rescue | K950 Ring | K960 | K960 Rescue | K960 Ring | K970 Ring | 3120 | 3120XP | 3120K | K950 Chain | K960 Chain | K970 Chain |
