Description
Overview:
This is a genuine Husqvarna throttle return spring for petrol chainsaws. It is a compact torsion spring made from durable spring steel that provides the tension needed to return the throttle to idle after you release the trigger. By reliably closing the throttle plate, it helps prevent over‐revving and supports safe, consistent engine control during cutting. Designed for a wide range of Husqvarna models, including the 350 and 357XP, it is a direct replacement for a worn, weakened, or lost spring. The metal construction resists fatigue under repeated use and is suitable for professional, agricultural, and domestic work. If your throttle feels slow to return or sticks open, replacing this spring is a straightforward, low‐cost fix that restores normal operation.
Key Features:
- Genuine Husqvarna part for correct fit and reliable operation across listed models
- Spring steel construction for strength, resilience, and long service life
- Ensures smooth, positive throttle return to idle to help avoid engine over‐revving
- Stable tension for consistent control during felling, pruning, and limbing tasks
- Direct replacement for the original spring; no modifications required
- Compact OEM form factor for easy installation in the throttle linkage area
- Suitable for regular professional use as well as DIY maintenance
- Compatible with popular models such as 350 and 357XP (see full list below)
Typical Applications:
Replacement of a fatigued, stretched, or broken throttle return spring on Husqvarna chainsaws. Ideal when the throttle does not snap back to idle, when idle speed hangs, or after carburettor/throttle linkage servicing. Helps maintain safe throttle control for firewood cutting, storm cleanup, landscaping, and forestry work.
Also known as:
Throttle spring, return spring, throttle torsion spring, carburettor throttle return spring, throttle linkage spring, accelerator spring, control lever return spring.
Fits Models:
340, 340E, 345, 345E, 345E TrioBrake, 346XP, 346XP TrioBrake, 350, 351, 353, 353 TrioBrake, 357XP, 359, 455 Rancher, 455 Rancher II, 455E, 455E Rancher II, 455E TrioBrake, 460, 461, 465 Rancher II
Alternate Part Numbers:
503 99 86-01, 503998601
Product Specifications
| L&S Part No. | 503 99 86 01 |
|---|---|
| Part Type | Genuine Part |
| Manufacturer | Husqvarna |
| OEM No. | 503998601 |
| Unit of Sale | 1 |
| Applications | 340, 340E, 345, 345E, 345E TrioBrake, 345ETrioBrake, 346XP, 346XP TrioBrake, 346XPTrioBrake, 350, 351, 353, 353 TrioBrake, 353TrioBrake, 357XP, 359, 455 Rancher, 455 Rancher II, 455 RancherII, 455E, 455E Rancher II, 455E Rancher II TrioBrake, 455E TrioBrake, 455ERancherII, 455ETrioBrake, 460, 461, 465 Rancher II, 465RancherII |
| Machine Type | Chainsaws |
| Fits Brands | Husqvarna |
| Fits Models | 340 | 340E | 345 | 345E | 345E TRIOBRAKE | 346XP | 346XP TRIOBRAKE | 350 | 351 | 353 | 353 TRIOBRAKE | 357XP | 359 | 455E | 455E RANCHER II | 455E RANCHER II TRIOBRAKE | 455E TRIOBRAKE | 455 RANCHER | 455 RANCHER II | 460 | 461 | 465 RANCHER II |
