STIHL FS 410 C-M K, 460 C-M K Brushcutter Instruction Manual

1 Introduction

Dear Customer,

Thank you for choosing STIHL. STIHL develops and manufactures quality products to meet customer requirements, designed for reliability even under extreme conditions. STIHL also stands for premium service quality, with dealers providing competent advice, instruction, and comprehensive service support. STIHL is committed to sustainable and responsible handling of natural resources. This user manual is intended to help you use your STIHL product safely and in an environmentally friendly manner over a long service life.

We thank you for your confidence and hope you will enjoy working with your STIHL product.

IMPORTANT! READ BEFORE USING AND KEEP IN A SAFE PLACE FOR REFERENCE.

2 Guide to Using this Manual

2.1 Applicable Documentation

Local safety regulations apply. Read, understand, and save the following documents in addition to this instruction manual:

• Instruction manual and packaging of the cutting attachment you are using.

2.2 Symbols used with warnings in the text

WARNING: This symbol indicates dangers that can cause serious injuries or death. The measures indicated can avoid serious injuries or death.

NOTICE: This symbol indicates dangers that can cause damage to property. The measures indicated can avoid damage to property.

2.3 Symbols in Text

This symbol ➡️ refers to a chapter in this instruction manual.

3 Overview

3.1 Brushcutter Components

The brushcutter comprises the following main components:

• 1 Filter cover: Covers the air filter.
• 2 Air filter: Filters the air entering the engine.
• 3 Manual fuel pump: Makes it easier to start the engine.
• 4 Shutter: Used to select summer or winter operating mode.
• 5 Cover: Covers the spark plug.
• 6 Spark plug boot: Connects the ignition lead to the spark plug.
• 7 Spark plug: Ignites the fuel-air mixture in the engine.
• 8 Muffler: Reduces brushcutter noise emissions.
• 9 Starter grip: Used for starting the engine.
• 10 Fuel tank cap: Closes the fuel tank.
• 11 Choke lever: Helps start the engine.
• 12 Carrying strip: Perforated strip for suspending the carrying system.
• 13 Control handle: Used for operating, holding, and controlling the brushcutter.
• 14 Throttle trigger: Controls the engine speed.
• 15 Throttle trigger lockout: Unlocks the throttle trigger.
• 16 Stop switch: Shuts off the engine.
• 17 Wing screw: Secures the handlebar to the handle support.
• 18 Handlebar: Connects control handle and handle with the shaft.
• 19 Handle: For holding and controlling the brushcutter.
• 20 Throttle cable: Connects the throttle trigger to the engine.
• 21 Shaft: Connects all components.
• 22 Gear housing: Encloses the gearbox.
• 23 Opening for stop pin: Accommodates the stop pin.
• 24 Stop pin: Blocks the shaft while a cutting attachment is being mounted.
• # Rating plate: Displays the machine number.

3.2 Equipment Features

Depending on the market, the brushcutter may have the following features:

• 1 Handle heating switch: Switches the handle heating on and off, heating the control handle and handle.

3.3 Deflectors and Cutting Attachments

The illustrations show examples of deflectors and cutting attachments. Approved combinations are listed in section 20.

• 1 Deflector for metal cutting attachments: Protects the user from thrown objects and contact with the grass cutting blade or brush knife.
• 2 Brush knife: Cuts brushwood.
• 3 Limit stop: Protects the user from flying debris and contact with the circular saw blade, and helps support the trimmer against the wood during cutting.
• 4 Circular Saw Blade: Cuts shrubs and trees.
• 5 Transport guard: Protects the user from contact with metal cutting attachments.

3.4 Symbols

Meanings of symbols that may be on the trimmer and the deflector:

• ⛽: Fuel tank.
• Shutter in winter mode position.
• Shutter in summer mode position.
• ?: Stop switch.
• ?: Handle heating switch.
• ?: Direction of rotation of the cutting attachment.
• ?: Maximum diameter of the cutting attachment in millimeters.
• ⚡: Rated speed of the cutting attachment.
• LWA: Guaranteed sound power level in dB(A) for the purpose of comparing sound emissions of products in accordance with Directive 2000/14/EC.

4 Safety Precautions

4.1 Warning Signs

4.1.1 Warning Symbols

Meanings of warning signs on the trimmer:

• ⚠️: Observe safety notices and take the necessary precautions.
• ?: Read, understand, and save the instruction manual.
• ?: Wear safety glasses.
• ?: Wear hearing protection.
• ⛑️: Wear a hard hat.
• ?: Wear safety boots.
• ?: Wear work gloves.
• ⛽: Manual fuel pump.
• Shutter is in winter mode ❄️.
• Shutter is in summer mode ☀️.
• Observe safety notices on kickback ↩️ and take necessary precautions.
• Observe safety notices on flying debris ? and take necessary precautions.

? 15m (50ft): Maintain safe distance.

?: Do not touch hot surface.

4.1.2 Deflector for metal cutting attachments

Meanings of warning signs on the deflector for metal cutting attachments:

• Use this deflector for grass cutting blades.
• Use this deflector for brush knives.
• Do not use this deflector for mowing heads.
• Use this deflector for shredder blades.
• Do not use this deflector for circular saw blades.

4.2 Intended Use

The STIHL FS 410 C-M K, 460 C-M K brushcutter is designed for:

• With a brush knife: Cutting brush with a stem diameter up to 20 mm.
• With a circular saw blade: Cutting shrubs and trees with a stem diameter up to 70 mm.

Using the brushcutter for purposes other than those it is designed for may result in serious or fatal injuries and damage to property. Use the brushcutter as described in this User Manual.

4.3 The Operator

Users who have had no instruction cannot recognize or assess the risks involved in using the trimmer, potentially leading to serious or fatal injuries. Read, understand, and save the instruction manual. If passing the trimmer on, always provide the manual. Ensure the user is rested, in good physical and mental condition, of legal age or supervised training, aware of risks, and has received prior instruction from a STIHL dealer or experienced user. Do not operate under the influence of alcohol, medication, or drugs. Contact a STIHL dealer for queries.

The trimmer's ignition system produces an electromagnetic field that may interfere with pacemakers, potentially causing serious or fatal injuries. If the user has a pacemaker, ensure it is not affected.

4.4 Clothing and Equipment

Long hair can be drawn into the brushcutter, causing serious injury. Tie up and confine long hair above shoulders.

Objects can be thrown at high speed during operation, causing injury. Wear close-fitting safety glasses (tested to EN 166 or national regulations), face protection, long trousers made from resistant material.

Noise generated during operation can damage hearing. Wear ear protection.

Falling objects can cause head injuries. If objects are likely to fall, wear a hard hat.

Dust whipped up during operation can damage respiratory passages and cause allergic reactions. If dust is generated, wear a dust respirator mask.

Inappropriate clothing can snag on wood, brush, or the brushcutter, risking serious injury. Wear close-fitting clothing, remove scarves and jewelry.

The user may come into contact with the rotating cutting attachment, risking serious injury. Wear robust footwear, steel-toed safety boots if using metal cutting attachments, and long trousers made from resistant material.

Wearing unsuitable footwear may cause slipping and injury. Wear sturdy, closed-toed footwear with high-grip soles.

During mounting/dismounting cutting attachments, cleaning, or maintenance, contact with sharp edges can cause injury. Wear work gloves made from resistant material.

4.5 Working Area and Surroundings

Bystanders, children, and animals are unaware of the dangers of the brushcutter or flying debris, risking serious injury and property damage. Do not allow bystanders, children, or animals within 15 meters (50 ft) of the work area. Maintain a clearance of 15 meters from objects. Do not leave the brushcutter unattended. Ensure children cannot play with it.

Hot exhaust gas emitted from the muffler can ignite flammable materials and cause a fire. Keep exhaust gas well away from easily flammable materials.

4.6 Safe Condition

4.6.1 Brushcutter

The brushcutter is in a safe condition if:

• It is not damaged.
• There is no fuel leaking.
• The fuel tank cap is closed.
• It is clean.
• Controls function properly and have not been modified.
• An approved combination of cutting attachment and deflector is mounted correctly.
• Genuine STIHL accessories are fitted and correctly attached.
• All accessible screws and fastening parts are firmly tightened.

If not in safe condition, components may malfunction, safety devices may be disabled, and fuel leakage may occur, resulting in serious or fatal injury. Work only with an undamaged brushcutter. Contact a STIHL dealer if fuel is leaking. Close the fuel tank cap. Clean the brushcutter if dirty. Never modify the brushcutter, except for approved attachment combinations. Do not use if controls malfunction. Fit genuine STIHL accessories and mount attachments as described. Attach accessories as per manual. Tighten loose parts. Never insert objects into openings. Replace worn or damaged labels. Consult a STIHL dealer if in doubt.

4.6.2 Deflector

The deflector is in a safe condition if it is not damaged.

If not in safe condition, components may malfunction and safety devices may be disabled, resulting in serious injury. Work only with an undamaged deflector. Consult a STIHL dealer if unsure.

4.6.3 Metal cutting attachment

The metal cutting attachment is in a safe condition if:

• It and its mounting hardware are undamaged.
• It is not warped.
• It is properly mounted.
• It is correctly sharpened.
• Cutting edges have no burrs.
• Wear limits are not exceeded.
• If a non-STIHL attachment is used, it is not heavier, thicker, of different shape, lower quality, or larger in diameter than the largest approved STIHL attachment.

If not in a safe condition, parts may come off and be thrown at high speed, causing serious injury. Never work with damaged attachments or hardware. Sharpen and deburr correctly. Have attachments balanced by a STIHL dealer. Observe wear limits. Use specified attachments. Consult a STIHL dealer if in doubt.

4.7 Fuel Mixture and Refueling

This brushcutter requires a fuel mixture of gasoline and two-stroke engine oil. Mixed fuel and gasoline are extremely flammable and can cause fire or explosions if exposed to open fire or hot objects, leading to serious or fatal injury and property damage. Protect fuel from heat and fire. Do not spill fuel. Wipe up spills and ensure parts are dry before starting. Do not smoke. Never refuel near fire. Shut off the engine and allow it to cool before refueling. Start the engine at least 3 meters from the fueling spot, outdoors only.

Inhaling fuel and gasoline fumes can have toxic effects. Avoid inhaling fumes. Refuel in a well-ventilated location.

The brushcutter heats up during operation. Fuel expands, building pressure. Opening the fuel tank cap can release fuel spray, which can ignite and cause serious injury. Allow the brushcutter to cool down first, then open the fuel tank cap carefully.

Clothing in contact with fuel or gasoline ignites more easily, risking serious or fatal injury and property damage. Change clothing if it comes into contact with fuel or gasoline.

Fuel mix, gasoline, and two-stroke engine oil can harm the environment. Do not spill. Dispose of in accordance with local regulations.

Fuel, gasoline, or two-stroke engine oil can cause irritation on skin or eye contact. Avoid contact. Wash skin with soap and water. Rinse eyes with plenty of water for 15 minutes and consult a doctor.

The brushcutter's ignition system produces sparks. Unconfined sparks can cause fire or explosion in combustible environments, leading to serious or fatal injury and property damage. Use specified spark plugs, insert and tighten them, and connect the spark plug boot firmly.

The brushcutter can be damaged by using unsuitable gasoline, two-stroke oil, or incorrect mix ratios. Mix fuel as described. Fuel mixture can separate or age if stored long-term, damaging the brushcutter. Thoroughly mix fuel before refueling. Use fuel mix not older than 30 days (STIHL MotoMix: 5 years).

4.8 Working

If the engine is not started properly, the user may lose control, resulting in serious injury. Start the engine as described. Do not start the engine if the cutting attachment touches the ground or objects.

If the start flap lever is in the position (choke engaged) when starting, the engine speed is higher than idle, and the cutting attachment can rotate immediately. This may result in serious injury. Do not touch the cutting attachment. Start the engine as described. Ensure the choke lever is in the correct position for operation.

In certain situations, the user may lose concentration, control, stumble, or fall, leading to serious injury. Keep calm and plan work. Do not use in poor light or visibility. Operate alone. Keep the cutting attachment close to the ground. Watch for obstacles. Work standing on the ground and maintain balance. Take breaks if fatigued.

Exhaust gas produced when the engine is running can have toxic effects. Avoid inhaling exhaust gas. Operate in a well-ventilated location. If experiencing nausea, headache, visual disturbances, hearing problems, or dizziness, stop work and seek medical advice.

Hearing protection restricts the ability to hear and assess noises. Keep calm and plan work.

When working with the trimmer and the start flap lever is in the position (choke engaged), the user cannot work with the power brush in a controlled manner, risking serious injury. Check that the choke lever is in the position during operation. Start the engine as described. The rotating cutting attachment can cut the user, risking serious injury. Do not touch the rotating cutting attachment. If the cutting attachment is blocked, shut off the engine before clearing the jam.

Using mowing lines that are too long can damage the brushcutter. Use a suitable deflector with an attached line limiting blade. The machine can be damaged if the throttle is opened while the cutting attachment is blocked. Shut off the engine before clearing the jam.

If the trimmer's behavior changes or feels unusual during operation, it may no longer be in a safe condition, risking serious injury and property damage. Stop work and consult a STIHL servicing dealer.

Trimmer vibrations may occur during operation. Wear gloves, take breaks. If signs of circulatory disturbance occur, consult a doctor.

If the cutting attachment contacts a foreign object, the object or parts may be thrown at high speed, injuring persons or damaging property. Remove foreign objects from the working area.

If the rotating cutting attachment contacts a hard object, sparks may occur and the attachment may be damaged. Sparks can cause fires in flammable environments, leading to serious or fatal injury and property damage. Do not use in flammable environments. Ensure the cutting attachment is in a safe condition.

Note that the cutting attachment continues to rotate for a short period after the trigger is released, potentially causing serious injury. Wait until the cutting attachment comes to a complete stop.

In an emergency, the user may panic and forget to remove the carrying system, risking serious injury. Practice taking off the carrying system.

4.9 Reactive Forces

Kickout can be caused by the cutting attachment contacting a solid object or getting pinched in the cut, suddenly braking its rotation. The risk is greatest in the black area indicated in diagrams.

These situations can abruptly decelerate or stop rotation and throw the cutting attachment right or towards the user, causing loss of control and potentially serious or fatal injuries. Hold the trimmer firmly with both hands. Use described working techniques. Do not use the black area for cutting. Use approved combinations of cutting attachment, deflector, and carrying system. Sharpen the metal cutting attachment correctly. Cut with the motor running at full speed.

4.10 Transporting

The gearbox can get hot during operation, risking burn injuries. Do not touch a hot gearbox.

The trimmer may turn over or shift during transport, causing personal injuries and property damage. Shut off the engine. If a metal cutting attachment is mounted, fit the transport guard. Secure the trimmer with lashing straps or a net to prevent turnover and movement.

The muffler and engine may be hot after operation, risking burn injuries. Carry the trimmer properly balanced by the drive tube with the cutting attachment behind you.

4.11 Storing

Children are unaware of and cannot assess the dangers of a trimmer and can be seriously injured. Shut off the engine. If a metal cutting attachment is mounted, fit the transport guard. Store the trimmer out of the reach of children.

Dampness can corrode electrical contacts and metal components, damaging the trimmer. Store the trimmer in a clean and dry condition.

4.12 Cleaning, Maintenance and Repair

The cutting attachment can start rotating unintentionally if the engine is running during cleaning, maintenance, or repair, causing serious injury and property damage. Shut off the engine. Wait for the muffler and engine to cool down. Do not touch a hot gear housing.

Aggressive cleaning agents, water jets, or pointed objects can damage the trimmer, deflector, or cutting attachment. Improper cleaning can lead to component malfunction or disable safety devices, causing serious injury. Clean as described in this manual.

If the trimmer, deflector, or cutting attachment are not serviced or repaired correctly, components may malfunction or safety devices may be rendered inoperative, resulting in serious or fatal injury. Do not attempt to service or repair the trimmer or deflector yourself. Contact your STIHL servicing dealer for servicing or repairs. Maintain the cutting attachment as described in its user manual.

The user can be cut by sharp cutting edges while cleaning or maintaining cutting attachments, risking injury. Wear work gloves made from resistant material.

5 Preparing Trimmer for Operation

5.1 Preparing the Brushcutter for Operation

The following steps must be performed before commencing work:

• Ensure components are in safe condition: Brushcutter, Deflector, Metal cutting attachment.
• Clean the brushcutter.
• Mount the bike handle.
• Select combination of cutting attachment, deflector, and carrying system.
• Mount the deflector.
• Mount the metal cutting attachment.
• Fill the brushcutter with fuel.
• Fit and adjust the carrying system.
• Adjust the bike handle.
• Balance the brushcutter.
• Check the controls.

If you cannot perform these tasks, do not use the brushcutter and contact your STIHL dealer.

6 Assembling the Trimmer

6.1 Mounting the Bike Handle

Shut off the engine.

Steps:

1. Open the clamp of the toggle screw (1) and turn it counterclockwise until the handle tube (2) is only slightly clamped.
2. Insert the spring (5) from below into the lower clamp molding (4).
3. Place the clamp shells (3 and 4) on the shaft and insert the wing screw (1).
4. Pivot the handlebar (2) up and align it so that distance (A) is about 16 cm. Do not clamp the curved part of the handlebar (2) yet.
5. Tighten the wing screw (1) and close the clamp.
6. Remove the screw (6).
7. Position the control handle (8) on the handlebar (2), trigger facing the gear housing, and align the hole in the control handle with the hole in the handlebar. Do not twist the operating handle (8).
8. Fit the nut (7).
9. Insert and tighten down the screw (6) firmly. The bike handle does not need to be removed again.

6.2 Removing the Deflector and the Limit Stop

6.2.1 Installing the Deflector and the Limit Stop

Shut off the engine.

1. Position the deflector (1) on the gear housing.
2. Insert the screws (2) and tighten them securely.

6.2.2 Removing the Deflector and Limit Stop

1. Shut off the engine.
2. Take out screws.
3. Remove deflector.

6.3 Removing and Installing Metal Cutting Attachment

6.3.1 Mounting Brush Knives

Shut off the engine.

1. Attach the guard ring (7) for mowing applications.
2. Fit the thrust plate (6) and guard washer (5).
3. Place the brush knife (4) on the guard washer (5). The collar (a) must protrude into the hole (b) of the brush knife (4).
4. Place the thrust washer (3) on the brush knife (4) so that its convex side faces up.
5. Place the rider plate (2) for the mowing attachment on the thrust washer (3) so that its closed side faces up.
6. Insert the stop pin (9) in the hole up to the limit stop and hold it depressed.
7. Turn the brush knife (4) counterclockwise until the stop pin (9) engages in position, blocking the shaft (8).
8. Fit the nut (1) counterclockwise and tighten it down firmly.
9. Remove the stop pin (9).

6.3.2 Mounting the Circular Saw Blade

Shut off the engine.

1. Attach the guard ring (6) for sawing applications.
2. Fit the thrust plate (5).
3. Place the circular saw blade (4) on the thrust plate (5). Align the cutting edges so they face the same direction as the arrow for rotation on the limit stop. The collar (a) must engage the hole (b) of the metal cutting attachment.
4. Place the thrust washer (3) on the circular saw blade (4) so its convex side faces up.
5. Place the rider plate (2) for sawing applications on the thrust washer (3) so its closed side faces up.
6. Insert the stop pin (8) in the hole up to the limit stop and hold it depressed.
7. Turn the circular saw blade (4) counterclockwise until the stop pin (8) engages, blocking the shaft (7).
8. Fit the nut (1) counterclockwise and tighten it down firmly.
9. Remove the stop pin (8).

6.3.3 Removing the metal cutting attachment

1. Shut off the engine.
2. Insert the stop pin in the bore up to the limit stop and hold it depressed.
3. Rotate the metal cutting attachment clockwise until the stop pin engages, blocking the shaft.
4. Unscrew the mounting nut clockwise.
5. Remove the fastening parts, metal cutting tool, and pressure plate.
6. Remove the stop pin.

7 Adjusting Trimmer for User

7.1 Fitting and Adjusting the Full Harness

1. Put on the Full harness (1).
2. Adjust the full harness (1) so that the carabiner (2) is about a hand's width below your right hip.

7.2 Adjusting the Bike Handle

The bike handle can be set to different positions to suit the height and reach of the user.

1. Shut off the engine.
2. Hook the brushcutter from the carrying strip into the carabiner of the carrying system.
3. Loosen the wing screw (1).
4. Swing the bike handle (2) to the required position.
5. Tighten down the wing screw (1) firmly.

7.3 Balancing the Brushcutter

The brushcutter is balanced differently depending on the cutting attachment used.

• If a brush knife is fitted: The brush knife must just touch the ground.
• If a circular saw blade is fitted: The saw blade must hover at a height of about 20 cm above the ground.

Steps:

1. Shut off the engine.
2. Hook the perforated strip (2) into the carabiner (1).
3. Wait for the brushcutter to stop swinging.
4. Check the position of the cutting attachment. If adjustment is needed, hook the carabiner (1) into another hole in the hole bar (2) and let it swing out again.

8 Mixing Fuel and Refueling the Brushcutter

8.1 Mixing Fuel

The fuel required is a mixture of gasoline and two-stroke engine oil in a 1:50 ratio.

STIHL recommends using STIHL MotoMix. If mixing yourself, use only STIHL two-stroke engine oil or equivalent high-performance oil (JASO FB, FC, FD; ISO-L-EGB, EGC, or EGD). STIHL HP Ultra or equivalent is recommended to maintain emission limits.

• Ensure gasoline octane number is at least 90 RON and ethanol content is not more than 10% (27% for Brazil).
• Make sure the two-stroke engine oil meets requirements.

Examples for fuel mixes (1:50 ratio):

• 20 ml Two-stroke engine oil, 1 l gasoline
• 60 ml Two-stroke engine oil, 3 l gasoline
• 100 ml Two-stroke engine oil, 5 l gasoline

Pour two-stroke engine oil into a clean, approved fuel canister first, then add gasoline. Stir the fuel before topping up.

8.2 Fueling the brushcutter

1. Shut off the engine.
2. Place the brushcutter on a level surface with the fuel tank cap facing up.
3. Use a damp cloth to clean the fuel tank cap and the area around it.
4. Turn the tank cap counterclockwise until it can be removed.
5. Remove the fuel tank cap.

NOTICE: Exposure to light, sunlight, or extreme temperatures can accelerate fuel separation or aging, potentially damaging the brushcutter. Thoroughly mix fuel. Do not top up with fuel stored for more than 30 days (STIHL MotoMix: 5 years).

When topping up, ensure no fuel is spilled and the fuel level remains at least 15 mm below the tank edge.

6. Fit the fuel tank cap onto the tank opening.
7. Turn the tank cap clockwise and tighten it firmly by hand to close the fuel tank.

9 Starting and Stopping the Engine

9.1 Starting the engine

1. Place the brushcutter on a level surface so the cutting attachment does not touch the ground or other objects.
2. Remove the transport guard.
3. Depress the manual fuel pump (1) at least 5 times.
4. If the engine is warm: Leave the choke lever (2) in the ☀️ position.
5. If the engine is at ambient temperature: Push in the choke lever (2) at the edge and set it to the ❄️ position.

NOTICE: The brushcutter can be damaged if pressed into the ground with your foot or knee. Press the brushcutter against the ground with your left hand. Do not stand or kneel on the shaft.

6. Press the brushcutter against the ground with your left hand.
7. Pull the starter grip slowly with your right hand until you feel it engage.
8. Pull the starter grip quickly and allow the starter rope to rewind several times until the engine runs.
9. If the choke lever (2) was in the ❄️ position: Briefly press the throttle lever lockout (3) and the throttle trigger (4). The choke control (2) springs to the ☀️ position. The engine runs at idling speed.
10. If the engine is cold: Warm up the engine by briefly opening the throttle.
11. If the cutting attachment rotates at idle: Rectify the malfunction; the throttle cable adjustment is incorrect.
12. If the engine does not start: Move the choke lever (2) to the ☀️ position and try starting again.
13. If the engine is flooded: Try starting again with the choke lever (2) in the ☀️ position.

9.2 Shut off the engine

1. Release the throttle trigger (1) and throttle trigger lockout (2). The cutting attachment stops rotating.
2. Depress the stop switch (3). The engine stops.

If the engine does not stop:

• Move the choke lever to the ❄️ position. The engine stops.
• Do not use the trimmer and contact a STIHL servicing dealer for assistance, as there is a malfunction.

As long as the stop switch is pressed, the ignition is switched off. After releasing the stop switch, the ignition is switched on again.

10 Testing the Trimmer

10.1 Checking the controls

Throttle trigger lockout and throttle trigger

1. Shut off the engine.
2. Attempt to pull the trigger without depressing the lockout lever. If the trigger can be pulled, do not use the trimmer and contact a STIHL dealer; the throttle trigger lockout is defective.
3. Press the throttle trigger lockout and keep it pressed.
4. Depress the throttle trigger.
5. Release the throttle trigger and throttle trigger lockout.
6. If the trigger or trigger lockout is stiff or does not spring back to the idle position, do not use the trimmer and contact a STIHL dealer; the trigger or lockout is faulty.

Throttle cable adjustment

1. Start the engine.
2. Attempt to pull the trigger without depressing the lockout lever. If the engine accelerates, adjust the throttle cable; adjustment is incorrect.

Stop switch

1. Shut off the engine.
2. Start the engine.
3. Depress the stop switch. The engine stops.
4. If the engine does not stop: Move the choke lever to the ❄️ position. The engine stops. Do not use the trimmer and contact a STIHL servicing dealer; the brushcutter is defective.

11 Operating the Trimmer

11.1 Setting to winter mode

The carburetor may ice up at temperatures below +10 °C. The shutter must be set to winter mode for the carburetor to be heated by warm air from the engine.

NOTICE: The engine may overheat if operated in winter mode above +10 °C. Change setting to summer mode. Shut off the engine.

1. Take out the screw (1).
2. Pull out the shutter (2).
3. Hold the shutter (2) so the snowflake ❄️ points to the mark (3).
4. Insert the shutter (2).
5. Fit the screw (1).

When working at temperatures below -10 °C or in powder/drifting snow, a cover plate for the engine housing and an air filter with plastic webbing are required. These accessories are available from a STIHL servicing dealer.

11.2 Summer Operation

The shutter must be set to summer mode when working at temperatures above +10 °C.

1. Shut off the engine.
2. Take out the screw (1).
3. Pull out the shutter (2).
4. Hold the shutter (2) so the sun ☀️ points to the mark (3).
5. Fit the shutter.
6. Fit the screw (1).

11.3 Calibrating the brushcutter

The trimmer adjusts itself automatically for optimum performance. Calibration allows adjustment for faster, optimal running.

If the outside temperature is below -10 °C or the engine is cold:

1. Start the engine.
2. Fit the carrying system.
3. Hold and guide the brushcutter.
4. Warm up the engine at full throttle for about 1 minute.
5. Shut off the engine.
6. Remove the cutting attachment. This allows the brushcutter to reliably adjust itself to optimum performance.

Calibration process:

1. Move the choke lever to the ☀️ position.
2. Start the engine without depressing the throttle trigger. The engine runs, and the choke lever remains in the ☀️ position.
3. Run the engine for at least 30 seconds but no more than 60 seconds (A) without depressing the throttle trigger.
4. Hold and guide the brushcutter so the gearbox does not touch the ground or other objects.

NOTICE: The calibration process is aborted if the throttle trigger is released before it is properly calibrated. Restart the calibration process.

NOTICE: The trimmer can be incorrectly calibrated if the throttle trigger is not kept fully depressed during calibration, potentially damaging the brushcutter. Keep the throttle trigger fully depressed.

7. Depress the throttle trigger for at least 40 seconds (B) and hold it in that position. The engine accelerates, and the trimmer is calibrated. Engine speed fluctuates and increases perceptibly during calibration.
8. As soon as the engine speed drops noticeably (C): Release the throttle trigger. The engine runs at idling speed. The brushcutter is calibrated and ready for use.

If the engine stalls: Make another attempt to calibrate the trimmer.

If the engine stops repeatedly: Do not use the trimmer and contact a STIHL servicing dealer; the brushcutter is defective.

11. Shut off the engine.
12. Mount the cutting attachment.

11.4 Holding and Controlling the Brushcutter

1. Hook the carrying strip (2) onto the carabiner (1).
2. Hold the brushcutter firmly with your right hand on the control handle, wrapping your thumb around the handle.
3. Hold the brushcutter with your left hand on the left grip, enclosing the handle with your thumb.

11.5 Mowing

The cutting height is determined by the distance of the cutting attachment from the ground.

Mowing with a brush knife

• Mow with the left part of the metal cutting attachment.
• Move forward slowly in a controlled manner.

11.6 Thinning with a brush knife

• Dip the metal cutting attachment into the thicket from above.
• Do not lift the metal cutting tool above waist height.

11.7 Saws with a circular saw blade

• Support the left side of the deflector against the stem.
• Cut through the stem at full speed.
• Maintain a safety distance of at least 2 tree lengths to the next work area.

12 After Finishing Work

12.1 When Work is Finished

1. Shut off the engine.
2. Allow the trimmer to cool down.
3. If the brushcutter is wet: Allow it to dry.
4. Clean the brushcutter.
5. Clean the deflector.
6. Clean the cutting attachment.
7. If a metal cutting attachment is mounted: Fit the matching transport guard.

13 Transporting

13.1 Transporting the Trimmer

1. Shut off the engine.
2. If a metal cutting attachment is mounted: Fit the matching transport guard.
3. Carry the trimmer properly balanced by the drive tube with the cutting attachment behind you.

Transporting the trimmer in a vehicle

• Secure the trimmer to prevent turnover and movement.

14 Storing

14.1 Storing the Brushcutter

1. Shut off the engine.
2. If a metal cutting attachment is mounted: Fit the matching transport guard.
3. Loosen the wing screw (1) and unscrew it until the handlebar (2) can be rotated.
4. Turn the handlebar (2) clockwise through 90° and fold it down.
5. Tighten down the wing screw (1) firmly.
6. Ensure the brushcutter is stored out of the reach of children, and is clean and dry.

If storing for more than 30 days:

1. Remove the cutting attachment.
2. Open the fuel tank cap.
3. Drain the fuel tank.
4. Close the fuel tank.
5. If a manual fuel pump is fitted: Press the manual fuel pump at least 5 times.
6. Start the engine and run it at idling speed until it stops.

15 Cleaning

15.1 Cleaning the Trimmer

1. Shut off the engine.
2. Allow the trimmer to cool down.
3. Clean the trimmer with a damp cloth or STIHL resin solvent.
4. Clean cooling air slots with a soft brush.

15.2 Cleaning the Deflector and Cutting Attachment

1. Shut off the engine.
2. Clean the deflector and cutting attachment with a damp cloth or a soft brush.

16 Maintenance

16.1 Maintenance intervals

Maintenance intervals depend on ambient and operating conditions. STIHL recommends the following:

• After every 100 hours of operation: Replace the spark plug.
• Monthly: Have the fuel tank cleaned by a STIHL dealer. Have the pickup body in the fuel tank cleaned by a STIHL dealer.
• Annually: Have the pickup body in the fuel tank replaced by a STIHL dealer.

16.2 Sharpening and Balancing a Metal Cutting Attachment

Correctly sharpening and balancing metal cutting attachments requires practice. STIHL recommends having them resharpened and balanced by a STIHL servicing dealer.

Sharpen the metal cutting attachment as described in the instructions and on the packaging supplied with it.

17 Repairing

17.1 Repairing the Trimmer and Cutting Attachment

The trimmer and cutting attachment cannot be repaired by the user.

• If the trimmer or cutting attachment is damaged: Do not use it and contact your STIHL servicing dealer.

18 Troubleshooting

18.1 Troubleshooting the Brushcutter

Most problems can be attributed to the same cause. Carry out the following measures:

• Replace the air filter.
• Clean or replace the spark plug.
• Adjust shutter for winter or summer operation.
• If the problem continues: Carry out the measured listed below.

18.2 Replacing air filter

The air filter cannot be cleaned. It must be replaced if damaged or if there is a loss of engine power.

1. Shut off the engine.
2. Move the choke lever to the ❄️ position.
3. Take out the screws (1) and remove the filter cover (2).
4. Clean the area around the air filter (3) with a damp cloth or a soft brush.
5. Take out the air filter (3).
6. Install the new air filter (3).
7. Fit the filter cover (2).
8. Insert screws (1) and tighten.

18.3 Cleaning the Spark Plug

1. Shut off the engine.
2. Allow the trimmer to cool down.
3. Pull off the spark plug boot (3).
4. If the area around the spark plug (4) is soiled: Clean the spark plug (4) with a cloth.
5. Unscrew the spark plug (4).
6. Clean the spark plug (4) with a cloth.
7. If the spark plug (4) is corroded: Install a new spark plug (4).
8. Insert and tighten down the spark plug (4) firmly.
9. Press the spark plug boot (3) firmly home.
10. Install cover (2) and tighten screw (1).

18.4 Adjusting the Throttle Cable

1. Press the throttle trigger (1) and keep pressed.
2. Turn screw (2) clockwise until resistance is felt.
3. Turn the screw (2) clockwise through another half-turn.

19 Specifications

19.1 STIHL FS 410 C-M K brushcutter

• Displacement: 41.6 cm³
• Engine power according to ISO 8893: 2.0 kW (2.7 hp) at 9,000 rpm
• Idle speed: 2,700 rpm
• Max. output shaft speed: 10,130 rpm
• Approved spark plug: NGK CMR6H from STIHL
• Electrode gap of the spark plug: 0.5 mm
• Dry weight without cutting attachment and deflector: 8.5 kg
• Length without cutting tool: 1675 mm
• Maximum fuel tank capacity: 750 cm³ (0.75 l)

19.2 STIHL FS 460 C-M K brushcutter

• Displacement: 45.6 cm³
• Engine power according to ISO 8893: 2.2 kW (3.0 hp) at 9,500 rpm
• Idle speed: 2,700 rpm
• Max. output shaft speed: 10,130 rpm
• Approved spark plug: NGK CMR6H from STIHL
• Electrode gap of the spark plug: 0.5 mm
• Weight with empty fuel tank and without cutting attachment and deflector:
• FS 460 C-M K: 8.5 kg
• FS 460 C-M K with handle heating: 8.7 kg
• Length without cutting attachment: 1675 mm
• Maximum fuel tank capacity: 750 cm³ (0.75 l)

19.3 Sound Values and Vibration Values

The K-value for the sound pressure level is 2 dB(A). The K-value for the sound power level is 2 dB(A). The K-value for vibration level is 2 m/s².

• Control handle: 2.4 m/s².
• Left handle: 2.5 m/s².

For information on compliance with Employers' Vibration Directive 2002/44/EC see www.stihl.com/vib.

Using with a metal cutting attachment

FS 410 C-M K

• Sound pressure level Lpeq measured according to ISO 22868: 99 dB(A).
• Sound power level Lw measured according to ISO 22868: 109 dB(A).
• Vibration level ahv measured according to ISO 22867:
• Control handle: 2.6 m/s².
• Left handle: 2.5 m/s².

FS 460 C-M K

• Sound pressure level Lp measured according to ISO 22868:
• FS 460 C-M K: 100 dB(A).
• FS 460 C-M K with handle heating: 101 dB(A).
• Sound power level Lw measured according to ISO 22868:
• FS 460 C-M K: 110 dB(A).
• FS 460 C-M K with handle heating: 111 dB(A).
• Vibration level ahv measured according to ISO 22867:
• Control handle: 2.4 m/s².
• Left handle: 2.5 m/s².

19.4 REACH

REACH is an EC regulation (Registration, Evaluation, Authorisation and Restriction of Chemical substances). For information on compliance with the REACH regulation see www.stihl.com/reach.

19.5 Exhaust Emissions

The CO2 value measured in the EU type approval procedure is specified at www.stihl.com/co2. The measured CO2 value was determined on a representative engine under laboratory conditions and does not represent an explicit or implied guarantee of performance. Applicable exhaust emission requirements are fulfilled by intended usage and maintenance as described in this manual. Type approval expires if the engine is modified.

20 Combinations of Cutting Attachments, Deflectors and Carrying Systems

20.1 Combinations of Cutting Attachments, Deflectors and Carrying Systems

21 Spare Parts and Accessories

21.1 Spare parts and accessories

These symbols indicate original STIHL spare parts and original STIHL accessories.

STIHL recommends the use of original STIHL spare parts and accessories. STIHL cannot judge the reliability, safety, or suitability of other manufacturers' parts and therefore cannot warrant their use. Original STIHL spare parts and accessories are available from STIHL dealers.

22 Disposal

22.1 Disposing of the Brushcutter

Contact local authorities or your STIHL dealer for disposal information. Improper disposal can harm health and pollute the environment.

• Take STIHL products, including packaging, to a suitable collection point for recycling in accordance with local regulations.
• Do not dispose of with domestic waste.

23 EC Declaration of Conformity

23.1 Brushcutter STIHL FS 410 CM K, FS 460 C-M K

ANDREAS STIHL AG & Co. KG, Badstraße 115, D-71336 Waiblingen, Germany, declares under sole responsibility that the Brushcutter, brand STIHL, type FS 410 C-M K, FS 460 C-M K (Serial identification number: 4147) conforms to the relevant provisions of Directives 2011/65/EU, 2006/42/EC, 2014/30/EU, and 2000/14/EC. It has been developed and manufactured in compliance with standards EN ISO 11806-1, EN 55012, and EN 61000-6-1.

Measured and guaranteed sound power levels determined in accordance with Directive 2000/14/EC, Annex V:

• FS 410 C-M K: Measured 112 dB(A), Guaranteed 114 dB(A).
• FS 460 C-M K: Measured 113 dB(A), Guaranteed 116 dB(A).
• FS 460 C-M K with handle heating: Measured 114 dB(A), Guaranteed 116 dB(A).

Technical documents are deposited at ANDREAS STIHL AG & Co. KG, Produktzulassung (Product Licensing). The year of manufacture, country of manufacture, and serial number are specified on the rating plate.

Done at Waiblingen, 01.10.2021

ANDREAS STIHL AG & Co. KG

Dr. Jürgen Hoffmann, Director Product Certification & Regulatory Affairs

24 UKCA Declaration of Conformity

24.1 STIHL FS 410 C-M K, FS 460 C-M K brushcutter

ANDREAS STIHL AG & Co. KG, Badstraße 115, D-71336 Waiblingen, Germany, declares under sole responsibility that the Category: Brushcutter, Manufacturer's brand: STIHL, Type: FS 410 C-M K, FS 460 C-M K (Serial number: 4147) conforms to the relevant provisions of UK regulations: The Restriction of the Use of Certain Hazardous Substances in Electrical and Electronic Equipment Regulations 2012, Supply of Machinery (Safety) Regulations 2008, Electromagnetic Compatibility Regulations 2016, and Noise Emission in the Environment by Equipment for use Outdoors Regulations 2001. It has been manufactured in compliance with standards EN ISO 11806-1, EN 55012, and EN 61000-6-1.

Measured and guaranteed sound power levels determined in accordance with UK regulation Noise Emission in the Environment by Equipment for use Outdoors Regulations 2001, Schedule 8:

• FS 410 C-M K: Measured 112 dB(A), Guaranteed 114 dB(A).
• FS 460 C-M K: Measured 113 dB(A), Guaranteed 116 dB(A).
• FS 460 C-M K with handle heating: Measured 114 dB(A), Guaranteed 116 dB(A).

Technical documents are stored at ANDREAS STIHL AG & Co. KG.

The year of manufacture, country of manufacture, and serial number are specified on the rating plate.

Waiblingen, 01.10.2021

ANDREAS STIHL AG & Co. KG

pp

Dr. Jürgen Hoffmann, Director Product Certification & Regulatory Affairs