stihl fs110r manual

The STIHL FS 110 R is a professional-grade, lightweight clearing saw (brushcutter) designed for demanding vegetation control. It features a powerful 2-stroke engine with electronic ignition, a loop handle for comfortable operation, a straight shaft for reach, a semi-automatic choke, and a reliable cutting head or blade system. Below are key sections for safety, features, operation, maintenance, troubleshooting, and specifications.

1. Features at a Glance 2. Safety Instructions 3. Assembly & Preparation 4. Specifications 5. Controls and Components 6. Fuel & Lubrication 7. Starting & Operation 8. Cutting Attachments 9. Maintenance & Storage 10. Troubleshooting 11. Warranty & Support

Features at a Glance

Key components: 2-stroke engine, Loop handle with throttle trigger and stop switch, Straight drive shaft, Decompression valve, Semi-automatic choke (Matic-START), Anti-vibration system, Quick-release fuel and oil caps, and a versatile attachment interface.

FeatureDescription
Engine Type2-stroke, single-cylinder, air-cooled
DisplacementApprox. 30.1 cm³ (1.84 cu. in.)
Power OutputHigh power-to-weight ratio for professional use
Ignition SystemElectronic, capacitor discharge (CDI)
Starting SystemSTIHL Matic-START (semi-automatic choke)
Fuel Tank CapacityApprox. 0.55 liters (18.6 fl. oz.)
Oil Tank CapacityApprox. 0.23 liters (7.8 fl. oz.) for gearbox
Drive ShaftStraight, solid
Anti-VibrationIntegrated dampers in handle and shaft
Weight (without cutting attachment)Approx. 5.2 kg (11.5 lbs)

Safety Instructions

Read and understand all instructions before use. Wear proper PPE: safety glasses, hearing protection, gloves, sturdy boots, long pants, and a helmet with face shield when necessary.

  1. Clear work area of bystanders, especially children and pets.
  2. Inspect machine before each use: check for loose parts, damage, and proper function of controls.
  3. Use the correct cutting attachment for the material. Ensure cutting tool is sharp and undamaged.
  4. Always hold the unit firmly with both hands. Maintain secure footing and balance.
  5. Never operate the machine if tired, ill, or under the influence of drugs or alcohol.

WARNING! Risk of serious injury or death from rotating cutting tool, thrown objects, and fire/explosion from fuel. Follow all safety rules.

Assembly & Preparation

Unpack and inspect all parts. Assemble handle, attach cutting tool, and fill fluids.

  1. Attach Loop Handle: Align with mounting points on the shaft and secure with provided bolts.
  2. Install Cutting Attachment: Ensure engine is off and cool. Fit the correct trimmer head, blade, or brush knife, securing it according to instructions (e.g., using the appropriate nut and washer).
  3. Fill Fuel: Use clean, fresh fuel mixture (STIHL MotoMix® recommended or 50:1 gasoline to STIHL 2-stroke oil).
  4. Fill Gearbox Oil: Use STIHL gearbox oil or high-quality EP 90 gear oil.
  5. Check all fasteners for tightness.

CAUTION! Use only STIHL-approved cutting attachments and accessories. Incorrect assembly can cause failure and injury.

Specifications

Controls and Components

Main controls located on the loop handle and engine housing.

Handle Area: Throttle trigger with lockout, Stop switch (I/O), Throttle trigger lock (must be depressed to operate throttle). Engine Housing: Decompression valve (press to ease starting), Choke lever (part of Matic-START), Fuel tank cap, Oil tank cap, Air filter cover, Spark plug, Muffler. Shaft/Gearhead: Attachment interface, Gearbox oil fill plug.

Operation: Squeeze throttle trigger lock and throttle trigger to increase engine speed. Release throttle for idle. Press stop switch to "O" to stop engine.

Fuel & Lubrication

Use high-quality unleaded gasoline (min. 89 octane) mixed with STIHL 2-stroke engine oil at 50:1 ratio. For premixed fuel, use STIHL MotoMix®.

  1. Clean area around caps before opening.
  2. Fill fuel tank to indicated level. Avoid spilling.
  3. Fill gearbox oil tank with specified oil until it reaches the filler hole.
  4. Tighten caps securely.

Tip: Never use fuel older than 30 days. Store fuel in an approved container away from heat and sparks.

Starting & Operation

Starting procedure for cold and warm engine.

  1. Place unit on clear, flat ground. Ensure cutting attachment is free and clear.
  2. Press fuel primer bulb (if equipped) several times until fuel is visible.
  3. Set stop switch to "I" (Run).
  4. Press decompression valve (if equipped).
  5. For Cold Start: Place choke lever in closed position (up).
  6. Hold unit securely with one hand on handle, foot in the rear handle. Pull starter rope briskly until engine fires.
  7. Move choke lever to open position (down) and pull starter rope again to start.
  8. Allow engine to warm up at idle for about 30 seconds before applying load.
  9. To Stop: Release throttle, let engine idle briefly, then move stop switch to "O".

WARNING! Never drop-start or start the unit while holding it off the ground. Keep hands and feet away from the cutting attachment at all times.

Cutting Attachments

Supports various attachments for different tasks.

  1. Trimmer Head (Line): For grass and light weeds. Use correct diameter nylon line. Tap head on ground to advance line (bump feed).
  2. Circular Grass Blade: For thick grass and light brush. Ensure blade is sharp, balanced, and securely fastened.
  3. Brush Knife: For heavy brush and saplings. Inspect for cracks or damage before use.
  4. Always use the correct guard for the attachment installed.
  5. Sharpen or replace cutting tools when dull to maintain performance and reduce vibration.

WARNING! Always stop the engine and allow it to cool before changing or inspecting the cutting attachment. Wear heavy-duty gloves.

Maintenance & Storage

Regular maintenance ensures long life and safe operation. Perform daily checks and periodic servicing.

Daily/Before Use: Check fasteners, inspect cutting attachment, check for fuel/oil leaks, clean air intake and exterior. Periodic: Clean/Replace air filter, Check/Replace spark plug, Clean spark arrestor screen in muffler (if equipped), Check gearbox oil level and condition. Storage (Long-term): Drain fuel tank and run engine until it stops. Remove spark plug, add a few drops of oil into cylinder, pull starter slowly 2-3 times, reinstall plug. Clean entire unit. Store in a dry, secure place.

CAUTION! Perform maintenance only when engine is off and cool. Use only genuine STIHL replacement parts.

Troubleshooting

SymptomPossible CauseCorrective Action
Engine will not startNo fuel, flooded, spark plug faulty, switch offCheck fuel, open choke, dry plug, ensure switch is on "I".
Engine starts but diesClogged air filter, fuel line, carburetor issuesClean/replace air filter. Check fuel system.
Loss of powerDirty air filter, clogged fuel filter, exhaust blockedService air/fuel filters. Clean spark arrestor screen.
Excessive vibrationDamaged cutting tool, loose parts, bent shaftInspect and replace cutting tool. Tighten all fasteners.
Cutting attachment does not rotateDrive shaft/shear pin broken, gearbox damagedInspect shear pin (if equipped) and drive system.
Gearbox overheatingLow or incorrect oilCheck and fill with correct gearbox oil.

Note: For complex repairs, contact an authorized STIHL servicing dealer.

Warranty & Support

This product is covered by a STIHL Limited Warranty. Proof of purchase from an authorized STIHL dealer is required. Warranty does not cover damage from misuse, neglect, improper fuel, or unauthorized repairs.

For technical support, parts, or service, contact your local authorized STIHL dealer. Find a dealer at www.stihlusa.com or consult your local directory. Always provide the model name (FS 110 R) and serial number.

Safety and Operator's Manuals: Available for download at the STIHL website.

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