Stihl FS 350 Manual

The Stihl FS 350 is a professional-grade, high-power brushcutter/trimmer designed for demanding clearing and maintenance work. It features a powerful 2-stroke engine with anti-vibration system, ergonomic harness system, easy-start technology, a robust cutting head and shaft, and compatibility with a wide range of cutting attachments. Below are key sections for safety, features, operation, maintenance, and troubleshooting.

Features at a Glance

Key components: Powerful 2-stroke engine, Ergonomic harness, Anti-vibration system, Easy-start system, Quick-release cutting head, Solid drive shaft.

Safety Information

Read and understand all instructions before use. Always wear appropriate PPE.

1. Personal Protective Equipment (PPE): Always wear safety glasses, hearing protection, heavy-duty gloves, long pants, and sturdy boots.
2. Work Area Safety: Clear area of bystanders, especially children and pets. Be aware of thrown object hazards.
3. Fuel Safety: Refuel in a well-ventilated area with engine off and cool. Use only STIHL-approved gasoline/oil mix.
4. Operation Safety: Keep firm footing. Do not operate on steep slopes. Never operate with one hand.

WARNING! The cutting tool continues to rotate after the throttle is released. Keep away from the cutting attachment until it comes to a complete stop.

Assembly & Preparation

Unpack and inspect all parts. Assemble according to instructions.

1. Attach Handle: Secure the loop handle to the shaft at the desired position for operator comfort.
2. Install Harness: Connect the harness hooks to the attachment points on the machine.
3. Install Cutting Attachment: Fit the chosen trimmer head, blade, or brush knife, ensuring it is securely fastened with the proper tool.
4. Fuel Mix: Prepare fuel using high-quality unleaded gasoline (min. 89 octane) and STIHL 2-stroke engine oil at a 50:1 ratio. Shake well.
5. Fill Fuel Tank: Clean area around cap. Fill tank with the prepared fuel mixture.

CAUTION! Ensure all fasteners are tight before operation. Do not force parts during assembly.

Specifications

• Engine Power: High-performance professional engine.
• Displacement: [Specific cc value, e.g., 36.3 cc]
• Powerhead Weight: Approx. [e.g., 6.8 kg / 15 lbs] (without cutting attachment)
• Shaft Type:Solid drive shaft Cutting AttachmentsCompatible with trimmer heads, brush knives, circular blades HarnessErgonomic dual-point harness for operator comfort Throttle ControlHandle-mounted throttle trigger with lockout

  Safety Information

  Read and understand all instructions before use. Always wear appropriate PPE.

  1. Personal Protective Equipment (PPE): Always wear safety glasses, hearing protection, heavy-duty gloves, long pants, and sturdy boots.
  2. Work Area Safety: Clear area of bystanders, especially children and pets. Be aware of thrown object hazards.
  3. Fuel Safety: Refuel in a well-ventilated area with engine off and cool. Use only STIHL-approved gasoline/oil mix.
  4. Operation Safety: Keep firm footing. Do not operate on steep slopes. Never operate with one hand.

  WARNING! The cutting tool continues to rotate after the throttle is released. Keep away from the cutting attachment until it comes to a complete stop.

  Assembly & Preparation

  Unpack and inspect all parts. Assemble according to instructions.

  1. Attach Handle: Secure the loop handle to the shaft at the desired position for operator comfort.
  2. Install Harness: Connect the harness hooks to the attachment points on the machine.
  3. Install Cutting Attachment: Fit the chosen trimmer head, blade, or brush knife, ensuring it is securely fastened with the proper tool.
  4. Fuel Mix: Prepare fuel using high-quality unleaded gasoline (min. 89 octane) and STIHL 2-stroke engine oil at a 50:1 ratio. Shake well.
  5. Fill Fuel Tank: Clean area around cap. Fill tank with the prepared fuel mixture.

  CAUTION! Ensure all fasteners are tight before operation. Do not force parts during assembly.

  Specifications

  • Engine Power: High-performance professional engine.
  • Displacement: [Specific cc value, e.g., 36.3 cc]
  • Powerhead Weight: Approx. [e.g., 6.8 kg / 15 lbs] (without cutting attachment)
  • Shaft Type: Solid drive shaft.
  • Fuel Capacity: [e.g., 0.71 L / 24 fl. oz.]
  • Oil/Fuel Mix Ratio: 50:1 with STIHL 2-Stroke Engine Oil.
  • Sound Power Level: High - hearing protection required.
  • Vibration Level: Reduced by anti-vibration system.
  • Warranty: Limited commercial warranty (see manual for details).

  Controls and Components

  Familiarize yourself with all controls before starting.

  Main Components: Throttle trigger with lockout, Stop switch (On/Off), Choke lever, Primer bulb, Fuel tank cap, Spark plug boot, Starter grip, Harness attachment points, Shaft, Cutting attachment guard.

  Operation: The lockout must be depressed before the throttle trigger can be engaged. The choke is used for cold starts. The stop switch immediately cuts the ignition.

  Starting & Stopping the Engine

  Ensure machine is on a clear, flat surface. Operator must be in harness.

  1. Cold Start: Set stop switch to "I" (On). Press fuel primer bulb 5-10 times. Move choke lever to closed position. Pull starter rope sharply until engine 'fires'. Move choke lever to open position. Pull starter rope again to start engine.
  2. Warm Start: Set stop switch to "I". Choke open. Pull starter rope.
  3. Stopping: Release throttle trigger. Allow engine to idle briefly. Press stop switch to "0" (Off).

  Tip: Do not pull starter rope to its full extent or let go of the grip while rope is retracting.

  Operation & Cutting Techniques

  Always maintain secure footing and a firm grip with both hands.

  1. Basic Trimming: Use a smooth, sweeping motion from side to side, keeping the cutting head parallel to the ground.
  2. Brush Cutting: Use a blade attachment. Use a swinging, scything motion. Let the weight of the tool do the work.
  3. Tall Grass/Weeds: Work from top to bottom in layers to avoid bogging down the engine.
  4. Around Obstacles: Use the tip of the line or blade for precise cutting. Be aware of kickback.

  WARNING! Never use a metal blade for trimming near fences, buildings, or rocks due to severe kickback hazard.

  Maintenance Schedule

  Regular maintenance ensures performance, longevity, and safety.

  Interval	Task
  Before each use	Inspect for loose fasteners, damage. Check cutting attachment security.
  Daily	Clean air filter. Check fuel system for leaks.
  Every 25 hours	Clean spark plug, check electrode gap. Clean cooling fins.
  Every 50 hours	Clean fuel filter. Check drive shaft lubrication.
  Annually or as needed	Replace spark plug. Have carburetor adjusted by a STIHL dealer.

  CAUTION! Always disconnect the spark plug boot before performing any maintenance.

  Storage

  Prepare the machine properly for storage to prevent fuel system issues.

  1. Run the engine until the fuel tank is empty.
  2. Allow engine to cool completely.
  3. Clean the entire machine, removing grass, dirt, and debris.
  4. Store in a dry, secure place, out of reach of children.
  5. For long-term storage (over 30 days), have your STIHL dealer drain the carburetor.

  Warranty & Support

  STIHL Limited Warranty: This product is covered by a limited warranty for commercial use. See your STIHL Owner's Manual for full terms and conditions. For genuine STIHL parts, accessories, and service, contact an authorized STIHL servicing dealer. For support, visit www.stihlusa.com or contact STIHL Incorporated at 1-800-467-8445.

  Troubleshooting

  Symptom	Possible Cause	Corrective Action
  Engine will not start	No fuel, flooded engine, spark plug faulty, switch off	Check fuel level. Wait if flooded. Check/clean spark plug. Ensure stop switch is ON.
  Engine starts then dies	Clogged fuel filter, dirty air filter, carburetor issue	Replace fuel filter. Clean air filter. See dealer for carb adjustment.
  Loss of power	Dirty air filter, clogged spark arrestor screen, old fuel	Clean air filter. Clean spark arrestor screen. Use fresh fuel mix.
  Excessive vibration	Loose fasteners, bent shaft, unbalanced blade	Tighten all nuts/bolts. Inspect shaft for damage. Balance or replace blade.
  Cutting attachment does not spin	Drive shaft disconnected, clutch worn, debris in head	Check shaft connection. Inspect clutch. Clean cutting head.

  Dealer Service: For repairs beyond basic maintenance, take the unit to an authorized STIHL dealer.

  Support: 1-800-467-8445; www.stihlusa.com

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