STIHL FS 55 Petrol Brush Cutter Strimmer

Product Information

The FS 55 is a power tool designed for cutting grass, wild growth, shrubs, scrub, bushes, small diameter trees, and similar materials. It features a fuel tank for a gasoline and engine oil mixture, a decompression valve for easy starting, a manual fuel pump for priming, and a handle heating function for comfortable operation.
The power tool is equipped with various pictograms that provide important information about its features and operation. These pictograms include symbols for the fuel tank, decompression valve, manual fuel pump, tube of grease, intake air for summer and winter operation, and handle heating.

The user manual contains pictorial explanations of these symbols and their meanings. It also includes warning and caution symbols to indicate potential risks and precautions to be taken while using the power tool.

STIHL, the manufacturer of the FS 55, continuously strives to improve its products. As a result, there may be occasional modifications in design, engineering, and appearance that are not covered in the manual.

Product Usage Instructions

1. Before operating the FS 55, carefully read and understand the user manual.
2. Ensure that children, animals, and bystanders are at a safe distance from the machine during operation.
3. When not in use, lay down the machine in a way that it does not pose a danger to anyone. Make sure it cannot be used without authorization.
4. The user is responsible for any accidents or risks involving third parties or their property.
5. Do not lend or rent the power tool without providing the user manual. Ensure that anyone using the tool understands the information contained in the manual.
6. Check national, regional, and local regulations regarding the permitted hours of use for machines that emit noise.
7. Only operate the machine if you are well-rested, in good physical health, and in a good mental condition.
8. If you have any medical conditions that may be aggravated by strenuous work, consult your doctor before using the machine.
9. If you have a pacemaker, consult your physician and the pacemaker manufacturer to reduce any health risks associated with the electromagnetic field produced by the machine’s ignition system.
10. Do not operate the power tool if you have consumed alcohol, drugs, or medications that affect your ability to react.
11. Use the power tool only for cutting grass, wild growth, shrubs, scrub, bushes, small diameter trees, and similar materials.
12. Ensure that you only use cutting attachments and accessories that are explicitly approved for the FS 55 model by STIHL or are technically identical. Consult your dealer if you have any questions in this regard.
13. Use high-quality parts and accessories to avoid accidents and damage to the machine.

FS 55

2 – 35

Instruction Manual

Guide to Using this Manual

Pictograms
The meanings of the pictograms attached to the machine are explained in this manual.
Depending on the model concerned, the follow- ing pictograms may be attached to your machine.
Fuel tank; fuel mixture of gasoline and engine oil
Operate decompression valve
Manual fuel pump

Operate manual fuel pump
Tube of grease Intake air: Summer operation
Intake air: Winter operation
Handle heating

Symbols in text

WARNING
Warning where there is a risk of an accident or personal injury or serious damage to property.
NOTICE
Caution where there is a risk of damaging the machine or its individual components.
1.3 Engineering improvements
STIHL’s philosophy is to continually improve all of its products. For this reason we may modify the design, engineering and appearance of our products periodically. Therefore, some changes, modifications and improvements may not be covered in this man- ual.
2 Safety Precautions and Working Techniques
Because the machine is a high-speed fast-cutting power tool, special safety precautions must be observed to reduce the risk of personal injury. It is important that you read and understand the User Manual before commissioning and keep it in a safe place for future reference. Non-com- pliance with the User Manual may cause serious or even fatal injury. Observe all applicable local safety regulations, e.g. by trade organizations, social insurance institutions, labor safety authorities etc. If you have never used a power tool before: Have your dealer or other experienced user show you how to operate your machine ­ or

© ANDREAS STIHL AG & Co. KG 2022 0458-826-0121-B. VA3.F22.

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Safety Precautions and Working Techniques
attend a special course to learn how to operate it.
Minors should never be allowed to use the machine ­ except for apprentices over the age of 16 when working under supervision.
Children, animals and bystanders must remain at a distance.
When not using the machine, it must be laid down in such a way that it does not endanger anyone. Ensure that the machine cannot be used without authorization.
The user is responsible for accidents or risks involving third parties or their property.
Do not lend or rent your power tool without the User Manual. Be sure that anyone using it under- stands the information contained in this manual.
The use of machines that emit noise may be limi- ted to certain hours of the day as specified by national and/or regional or local regulations.
Anyone operating the machine must be well res- ted, in good physical health and in good mental condition.
If you have any condition that might be aggrava- ted by strenuous work, check with your doctor before operating a machine.
If you have a pacemaker: The ignition system of your machine produces an electromagnetic field of very low intensity. This field may interfere with some pacemakers. STIHL recommends that per- sons with pacemakers consult their physician and the pacemaker manufacturer to reduce any health risk.
Anyone who has consumed alcohol or drugs or medicines affecting their ability to react must not operate a power tool.
Depending on the cutting attachment fitted, use your power tool only for cutting grass, wild growth, shrubs, scrub, bushes, small diameter trees and similar materials.
The machine must not be used for any other pur- poses ­ risk of accidents!
Only use cutting attachments and accessories that are explicitly approved for this power tool model by STIHL or are technically identical. If you have any questions in this respect, consult your dealer. Use only high quality parts and accessories. in order to avoid the risk of acci- dents and damage to the machine.

English
STIHL recommends the use of original STIHL tools and accessories. They are specifically designed to match the product and meet your performance requirements.
Never attempt to modify your power tool in any way since this may increase the risk of personal injury. STIHL excludes all liability for personal injury and damage to property caused while using unauthorized attachments.
Do not use a high-pressure washer to clean the power tool. The solid jet of water may damage parts of the unit.
The guard provided with your machine may not protect the operator from all foreign objects (gravel, glass, wire etc.) ejected by the revolving cutting attachment. Ejected objects may also ric- ochet and strike the operator.

Clothing and equipment
Wear proper protective clothing and equipment. Clothing must be sturdy but allow complete freedom of movement. Wear close-fitting clothes such as a boiler suit, not a loose jacket. Do not wear clothing which could become trapped in wood, brush or moving parts of the machine. Do not wear a scarf, necktie or jewelry. Tie up and confine long hair above your shoulders. Wear safety boots with steel toe caps and non-slip soles.
Sturdy shoes with non-slip shoes are permissible only when using mowing heads.
WARNING
To reduce the risk of eye injuries, wear close-fitting safety glasses in accordance with European Standard EN 166. Make sure the safety glasses are a snug fit.
Wear face protection and make sure it is a good fit. Face protection alone is not sufficient to pro- tect the eyes.
Wear “personal” sound protection, e.g. ear defenders.
Wear a safety hard hat for thinning operations, when working in high scrub and where there is a danger of head injuries from falling objects.

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Wear sturdy protective gloves made of a resistant material (e. g. leather).

STIHL can supply a comprehensive range of per- sonal protective equipment.
2.2 Transporting the machine

2 Safety Precautions and Working Techniques
Open the fuel cap carefully to allow any pressure build-up in the tank to release slowly and avoid fuel spillage.
Only refuel the machine in a well ventilated place. If fuel has been spilled, immediately clean the machine ­ do not allow your clothes to be splashed with fuel. If that happens, change your clothes at once.
After refueling, close the fuel cap as tightly as possible.

Always stop the engine. Carry the machine hanging on the harness or by the shaft so that it is balanced. To reduce the risk of cut injuries, fit transport guard on the cutting attachment, even when car- rying the tool for short distances ­ see also “Transporting the Unit”.
Avoid touching hot parts of the machine and gearbox ­ risk of burns!
By vehicle: When transporting in a vehicle, prop- erly secure your machine to prevent turnover, damage and fuel spillage.

Refueling
Gasoline is an extremely flammable fuel. Keep clear of naked flames. Do not spill any fuel ­ do not smoke.
Always shut off the engine before refueling. Do not fuel a hot engine ­ fuel may spill and cause a fire.
4

002BA079 KN

This helps reduce the risk of unit vibrations caus- ing an incorrectly tightened fuel cap to loosen or come off and spill quantities of fuel.
Check for leaks. Do not start the engine if there is a fuel leak ­ serious or fatal burns could result!

Before starting
Check that your power tool is properly assem- bled and in good condition ­ refer to appropriate chapters in the User Manual. ­ Check the fuel system for leaks, especially the
visible parts, e. g., fuel cap, hose connections, manual fuel pump (only in machines with a manual fuel pump). In case of leakage and damage, do not start the engine ­ risk of fire! Have the machine serviced by a dealer before using it ­ Use only an approved combination of cutting attachment, deflector, handle and harness. All parts must be assembled properly and securely ­ Slide control / stop switch must move easily to STOP or 0 ­ Throttle trigger lockout (if installed) and throttle trigger must move easily ­ the throttle trigger must return to the idle position automatically ­ Check that the spark plug boot is secure ­ a loose boot may cause sparking that could ignite combustible fumes and cause a fire! ­ Cutting attachment or interchangeable attach- ment: correctly fitted, secure and in perfect condition ­ Safety devices (e. g., deflector for cutting attachments, rider plate) for damage and/or wear. Always replace damaged parts. Do not use the machine with a damaged deflector or worn rider plate (if the writing and arrows are no longer discernible) ­ Never attempt to modify the controls or safety devices
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2 Safety Precautions and Working Techniques
­ Keep the handles dry and clean ­ free from oil and dirt ­ this is important for safe control of the machine
­ Adjust the harness and handle(s) to suit your height and reach Observe the chapter “Fitting the Harness” ­ “Balancing the machine”
To reduce the risk of personal injury, do not operate your power tool if it is damaged or not properly assembled!
To prepare for emergencies when using a har- ness: Practice setting down the machine quickly. To avoid damage, do not throw the unit to the ground when practicing.
2.5 Starting the engine
Start the engine at least 3 meters from the fuel- ing spot, outdoors only.
Place the unit on firm ground in an open area. Make sure you have good balance and secure footing. Hold the unit securely. The cutting attachment must be clear of the ground and all other obstructions because it may begin to run when the engine starts.
This is a one-person machine ­ ensure that there is no-one within 15 meters of the machine, not even when starting the power tool! Risk of injury due to ejected objects!
Avoid contact with the cutting attach- ment ­ risk of injury!
Do not drop-start the power tool ­ start the engine as described in the User Manual. The cutting attachment runs on for a short while after releas- ing the throttle trigger ­ coasting effect!
Check engine idling: The cutting attachment must remain at a standstill when the engine idles ­ throttle trigger released.
Keep easily combustible materials (e. g., wood chips, bark, dry grass, fuel) away from hot exhaust gases and hot muffler surfaces ­ risk of fire!
2.6 Holding and guiding the machine
Always hold the unit firmly with both hands on the handles.
Make sure you always have good balance and secure footing.
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2.6.1

English For versions with bike handle

002BA055 KN

Right hand on control handle, left hand on grip on handlebar.
2.6.2 For versions with loop handle

002BA080 KN

For versions with loop handle and loop handle with barrier bar, left hand on the loop handle, right hand on the control handle ­ even if you are left- handed.
2.7 While working
Make sure you always have good balance and secure footing.
In the event of impending danger or in an emer- gency, switch off the engine immediately – move the slide control/stop switch to STOP or 0.
15m (50ft)
Within a wide area around the workplace, there is a risk of accident by ejected objects, therefore ensure that there is no-one within a 15 m radius of the machine. This distance must also be main- tained in relation to objects (vehicles, window panes) ­ risk of property damage! Even at a dis- tance over 15 m, danger cannot be ruled out.
Check that the engine is properly idling so that the cutting tool will not continue rotating after you release the throttle trigger.
Check and correct the idle speed setting at regu- lar intervals. If the cutting attachment still rotates at idle speed, have your dealer make proper
5

English
adjustments or repairs. STIHL recommends you have this work done by a STIHL servicing dealer.
Take special care in slippery conditions ­ damp, snow, ice, on slopes or uneven ground.
Watch out for obstacles: tree stumps, roots ­ risk of tripping or stumbling!
Only work while standing on the ground, never on a ladder or mobile elevated work platform.
Be particularly alert and cautious when wearing hearing protection because your ability to hear warnings (shouts, alarms, etc.) is restricted.
Take breaks when you start getting tired or feel- ing fatigue ­ risk of accidents!
Work calmly and carefully ­ in daylight conditions and only when visibility is good. Proceed with caution, do not put others in danger.
As soon as the engine is running, the power machine generates toxic exhaust gas.As soon as the engine is running, the power machine gener- ates toxic exhaust gas. These gases may be odorless and invisible and may contain unburned hydrocarbons and benzene. Never run the engine indoors or in poorly ventilated loca- tions, even if your model is equipped with a catalytic converter.
To reduce the risk of serious or fatal injury from breathing toxic fumes, ensure proper ventilation when working in trenches, hollows or other con- fined locations.
Stop work immediately if you start suffering from nausea, headaches, impaired vision (e.g. your field of vision gets smaller), impaired hearing, dizziness, or impaired concentration ­ these symptoms may possibly be the result of too- high exhaust gas concentration ­ Risk of accidents!
Operate your power tool so that it produces a minimum of noise and emissions ­ do not run the engine unnecessarily, accelerate the engine only when working.
To reduce the risk of fire, do not smoke while operating or standing near your power tool. Com- bustible fuel vapor may escape from the fuel sys- tem.
Dust, fumes and smoke produced while working may be hazardous to health. Wear respiratory protection in case of heavy dust or smoke emis- sion.
If your power tool is subjected to unusually high loads for which it was not designed (e.g. heavy

2 Safety Precautions and Working Techniques
impact or a fall), always check that it is in good condition before continuing work ­ see also “Before Starting”.
Check in particular that the fuel system has no leaks and the safety equipment is fully operative. Never use a power tool that is no longer safe to operate. In case of doubt, contact a dealer.
Do not operate your power tool in the starting throttle position ­ engine speed cannot be con- trolled in this position.
To reduce the risk of injuryfrom ejec- ted objects, never operate the unit without the proper deflector for the type of cutting attachment being used. Check the work site ­ rocks, metal objects etc. may be caught up and ejected ­ possibly over a distance of 15 m ­ risk of injury! ­ They can also damage the cutting attachment and other property (e. g. parking vehicles, windows).
Be particularly careful when working on difficult, densely grown terrain.
When mowing in high shrubbery, under shrub- bery and hedges: Hold the cutting tool at a work- ing height of at least 15 cm ­ avoid risks to ani- mals.
Always shut off the engine before leaving the unit unattended.
Examine the cutting attachment periodically at short intervals and as soon as you note any noticeable changes: ­ Stop the engine, hold the machine securely,
allow the cutting attachment to come to a stop ­ Check condition and secure fitting; watch out
for cracks ­ Ensure that the cutting blades are sharp ­ Replace damaged or blunt cutting attachments
immediately, even in the event of minor hair- line cracks
Clean grass and plant residue off the cutting attachment mounting at regular intervals ­ remove any accumulated material from the cut- ting attachment and deflector.
To reduce the risk of injury, shut off the engine before replacing the cutting attachment.
The gearbox gets hot during opera- tion. Never touch the gearbox ­ risk of burns!

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2 Safety Precautions and Working Techniques
If a rotating cutting attachment touches a rock or another hard object, sparks can be generated which may possibly ignite combustible materials. Also dried- out plants and brushwood are com- bustible, above all in hot and dry weather. If there is a risk of fire, do not use cutting attach- ments in the vicinity of combustible materials, dried-out plants or brushwood. It is mandatory that you ask the responsible forestry office about current fire hazards.
2.8 Using mowing heads
Extend the cutting attachment deflector with the attached parts specified in the User Manual.
Only use a deflector with a properly fitted blade that limits the mowing line to the permissible length.
For manually adjustable mowing heads, always switch off the engine before adjusting the mow- ing line ­ risk of injury!
Misuse with mowing lines that are too long reduces the working speed of the engine. The constant slipping of the clutch causes overheat- ing and damage to important components (e. g. clutch, plastic housing parts) ­ e. g. due to the cutting attachment rotating during idling ­ risk of injury!
2.9 When using metal cutting attachments
STIHL recommends the use of original STIHL metal cutting attachments. These have been optimized for the machine and the user’s require- ments.
Metal cutting attachments rotate very fast, gener- ating forces acting on the attachments and on the cuttings.
Metal cutting attachments must be sharpened in regular intervals in accordance with the instruc- tions.
Unevenly sharpened metal cutting attachments generate an imbalance which may cause extreme loads on the machine ­ risk of break- age!
Dull or improperly sharpened cutting edges can put a higher load on the cutting attachment and increase the risk of injuryfrom cracked or broken parts.
After each contact of the metal cutting attach- ment with hard objects (e.g. stones, rocks, metal parts), check it for damage (e.g. tears and defor-
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English
mation). To reduce the risk of injury, remove burrs and other visible accumulated material because they may become detached and ejec- ted at high speed during operation.
Do not continue using or attempt to repair dam- aged or cracked cutting attachments by means of welding, straightening or modifying the shape (unbalanced).
Particles or pieces may come off and hit the operator or a bystander at a high speed ­ risk of most severe injuries!
To reduce the above-named risks involved in operating a metal cutting attachment, ensure that the diameter of your metal cutting attachment is not too big. Also, the attachment must not be too heavy. It must be made of high- quality materials and have a suitable geometry (shape, thickness).
A metal cutting attachment not made by STIHL must not have a different weight, thickness, shape or a larger diameter than the largest STIHL metal cutting attachment approved for this metal cutting attachment ­ risk of injury!
2.10 Vibrations
Prolonged use of the power tool may result in vibration-induced circulation problems in the hands (whitefinger disease).
No general recommendation can be given for the length of usage because it depends on several factors.
The period of usage is prolonged by: ­ Hand protection (wearing warm gloves) ­ Work breaks
The period of usage is shortened by: ­ Any personal tendency to suffer from poor cir-
culation (symptoms: frequently cold fingers, tingling sensations). ­ Low outside temperatures. ­ The force with which the handles are held (a tight grip restricts circulation).
Continual and regular users should monitor closely the condition of their hands and fingers. If any of the above symptoms appear (e.g. tingling sensation in fingers), seek medical advice.
2.11 Maintenance and Repairs
Service the machine regularly. Do not attempt any maintenance or repair work not described in the instruction manual. Have all other work per- formed by a servicing dealer.
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English
STIHL recommends that you have servicing and repair work carried out exclusively by an author- ized STIHL servicing dealer. STIHL dealers are regularly given the opportunity to attend training courses and are supplied with the necessary technical information.
Only use high-quality replacement parts in order to avoid the risk of accidents and damage to the machine. If you have any questions in this respect, consult a servicing dealer.
STIHL recommends the use of original STIHL replacement parts. They are specifically designed to match your model and meet your performance requirements.
To reduce the risk of injury, always shut off the engine before carrying out any maintenance or repairs or cleaning the machine. ­ Exception: Carburetor and idle speed adjustments.
Do not turn the engine over on the starter with the spark plug boot or spark plug removed unless the slide control / stop switch is on STOP or 0 since there is otherwise a risk of fire from uncontained sparking.
To reduce the risk of fire, do not service or store your machine near open flames.
Check the fuel filler cap for leaks at regular inter- vals.
Use only a spark plug of the type approved by STIHL and make sure it is in good condition ­ see “Specifications”.
Inspect the ignition lead (insulation in good con- dition, secure connection).
Check the condition of the muffler.
To reduce the risk of fire and damage to hearing, do not operate your machine if the muffler is damaged or missing. ­
Do not touch a hot muffler since burn injury will result.
2.12 Symbols on Deflectors
An arrow on the deflector shows the correct direction of rotation of the cutting attachments.
Some of the following symbols are applied to the outside of the deflector to indicate the approved combination of cutting tool and deflector.
Use deflector in combination with mowing heads only. Do not use metal cutting attachments.

2 Safety Precautions and Working Techniques Do not use deflector with brush kni- ves or circular saw blades. Do not use deflector with mowing heads. Use deflector in combination with grass cutting blades only.
2.13 Shoulder strap
Use a shoulder strap. With the engine running, attach the machine to
the shoulder strap. Grass cutting blades must always be used in combination with a shoulder strap.
2.14 Mowing Head with Nylon Line

000BA015 KN

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2 Safety Precautions and Working Techniques
Nylon line achieves a soft cut for edging and trimming around trees, fence posts, etc. ­ less risk of damaging tree bark.
The mowing head comes with an instruction leaf- let. Refill the mowing head with nylon line as described in the instruction leaflet.
WARNING
To reduce the risk of serious injury, never use wire or metal-reinforced line in place of the nylon line.
2.15 STIHL Polycut Mowing Head with Polymer Blades
For mowing unobstructed edges of meadows (without posts, fences, trees or similar obsta- cles).
Check the wear limit marks!

English
WARNING Never use wire in place of the nylon mowing line ­ risk of injury.
2.16 Risk of Kickout (Blade Thrust) with Metal Cutting Attachments
WARNING When using metal cutting attach- ments there is a risk of kickout when the rotating blade comes into contact with a solid object such as a tree trunk, branch, tree stump, rock or similar. The machine is thrown to the right or to the rear ­ opposite to the attachment’s direction of rotation.

002BA049 KN
002BA135 KN

If one of the wear limit marks on the PolyCut mowing head is worn through (arrow): Do not continue using the mowing head. Install a new one. There is otherwise a risk of injury from thrown parts of the head.
It is important to follow the maintenance instruc- tions for the PolyCut mowing head.
The PolyCut can also be equipped with mowing line in place of the polymer blades.
The mowing head comes with instruction leaflets. Equip the mowing head with polymers blades or nylon line as described in the instruction leaflets.

The risk of kickout is greatest when the black area of the rotating cutting attachment comes into contact with a solid object.

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English

3 Approved Combinations of Cutting Attachment, Deflector, Handle an…

2.17 Grass Cutting Blade

Use for grass and weeds only ­ sweep the brushcutter in an arc like a scythe.

WARNING

Improper use may damage the grass cutting blade ­ risk of injury from thrown parts.

Resharpen the grass cutting blade according to instructions when it has dulled noticeably.

000BA020 KN

3 Approved Combinations of Cutting Attachment, Deflector, Han- dle and Harness

Cutting attachment

Deflector

Handle

Carrying strap

1

2

3

23

4

5

6

15 19 21

16

17

7

8

9

20 21 18

10

11

14

12

3.1 Permissible combinations
Choose the correct combination from the table depending on the cutting tool!
10

16 18

17 20 21

0458-826-0121-B

0000078668_004

Mounting the Bike Handle

WARNING
For safety reasons only the cutting attachments, deflector, handle and harness versions within one line of the table may be combined with one another. No other combinations are permitted because of the risk of accidents!

Cutting attachments
3.2.1 Mowing heads 1 STIHL SuperCut 202 2 STIHL AutoCut C 25-2 3 STIHL AutoCut 25-2 / AutoCut 27-2 4 STIHL AutoCut C 26-2 5 STIHL TrimCut 31-2 6 STIHL TrimCut 32-2 7 STIHL DuroCut 20-2 8 STIHL PolyCut 20-3 9 STIHL PolyCut 28-2
3.2.2 Metal cutting tools 10 Grass cutting blade 230-2
(230 mm dia.) 11 Grass cutting blade 230-4
(230 mm dia.) 12 Grass cutting blade 230-8
(230 mm dia.)
WARNING
Grass cutting blades of materials other than metal must not be used.
3.3 Deflectors
13 Deflector for mowing heads 14 Deflector for metal cutting attachments
3.4 Handles
15 Loop handle 16 Loop handle with 17 Barrier bar 18 Bike handle
3.5 Shoulder straps
19 Shoulder strap can be used 20 Shoulder strap must be used

English 21 Full harness can be used
4 Mounting the Bike Handle
4.1 Mounting the Handlebar
5
67
4 2
3 1
Position the clamp (1) and handlebar sup- port (2) on the shaft (3)
Place the handlebar (4) in the handlebar sup- port ­ the rubber handle (5) must be on the left (viewing direction from engine to handlebar)
Place the clamp (6) on the handlebar support Insert the screws (7) through the holes in the
parts and screw them into the clamp (6) as far as they will go

233BA025 KN

0458-826-0121-B

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English
A
4
3
Fasten the handlebar (4) at a distance (A) of approx. 15 cm (6 in) ahead of the engine housing on the shaft (3)
Line up the handlebar and tighten down the screws firmly
4.2 Mounting the Control Handle

233BA018 KN 233BA027

4 Mounting the Bike Handle Unscrew the bolt (8) with a combination
wrench or hex key wrench ­ the nut (9) remains in the control handle (10) Push the control handle with the throttle trig- ger (11) facing toward the gearbox onto the handlebar (4) until the holes (12) align Insert and tighten screw (8)
4.3 Fastening the Throttle Cable
NOTICE
Do not kink the throttle cable or lay it in tight radii ­ make sure the throttle trigger moves freely.
14 13
13 14
Position the throttle cable retainer (14) and the throttle cable (13) on the shaft
Squeeze the throttle cable retainer (14). The throttle cable retainer (14) engages in position with an audible click

11

10 8
9

12 4
12

002BA357 KN

12

0458-826-0121-B

5 Mounting the Loop Handle
5 Mounting the Loop Handle
5.1 Mounting Loop Handle with Barrier Bar
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English
Position the clamp (6) against the drive tube. Place the barrier bar (2) in position as shown. Line up the holes. Insert the screws (7) in the holes and screw
them into the barrier bar (2) as far as stop. Go to “Securing the Loop Handle”.
5.2 Mounting the Loop Handle without Barrier Bar

7

7

8

84

002BA614 KN

1 1

Fit the square nuts (1) in the barrier bar (2); the holes must line up.

4

2

3

002BA098 KN

3
5
6 1
1
Place the clamp (3) in the loop handle (4) and position them both against the drive tube (5).
Position the clamp (6) against the drive tube. Line up the holes. Fit washers (8) on the screws (7) and insert
the screws in the holes. Fit the square nuts (1) and screw them down as far as stop. Go to “Securing the Loop Handle”.

5
6 7

002BA099 KN

Place the clamp (3) in the loop handle (4) and position them both against the drive tube (5).

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5.3 Securing the Loop Handle

6 Fitting the Carrying Ring

002BA615 KN 002BA142 KN

1

A

4

9

1

2

The loop handle can be adjusted to suit the height and reach of the operator and the applica- tion by changing distance (A).
Recommendation: distance (A): about 20 cm (8 in) Slide the handle to the required position. Line up the loop handle (4). Tighten down the screws until the loop handle
can no longer be rotated on the drive tube. If no barrier bar is fitted ­ lock the nuts if neces- sary.
The sleeve (9) (not fitted on all models) must be between the loop handle and the control handle.
6 Fitting the Carrying Ring
6.1 Metal Version
The carrying ring comes standard with the machine or is available as a special accessory.

For position of carrying ring see “Main Parts”. Place the clamp (1) against the drive tube with
the tapped hole on the left (viewed from engine). Squeeze the two ends of the clamp together and hold in that position. Insert the M6x14 screw (2). Line up the carrying ring. Tighten down the screw firmly.

14

0458-826-0121-B

002BA263 KN

7 Mounting the Deflector
6.2 Polymer Version
1

English
WARNING Deflector (1) is approved for mowing heads only and must therefore be mounted before fitting a mowing head
2

For position of carrying ring see “Main Parts”. Push the carrying ring (1) over the drive tube. Insert the M5 nut in the hex recess in the car-
rying ring. Fit the M5x14 screw. Line up the carrying ring. Tighten down the screw firmly.
7 Mounting the Deflector
7.1 Use the right deflector
1

002BA529 KN

WARNING Deflector (2) is approved for grass cutting blades only and must therefore be mounted before fit- ting a grass cutting blade.
7.2 Mounting the deflector
Deflectors (1) and (2) are both mounted to the gearbox in the same way.
Position the deflector against the gearbox so that the lug (3) engages the recess (4) in the deflector.
Insert the screw (5) and tighten it down firmly. On some versions the M5x14 screw is packed loose with the deflector.

0414BA007 KN

002BA262 KN

0458-826-0121-B

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English
8 Mounting the Cutting Attachment
8.1 Placing power tool on the ground

8 Mounting the Cutting Attachment

Depending on the cutting attachment, it may be necessary to use the nut (3), rider plate (4) and thrust washer (5).
These parts are included in a kit supplied with the machine and are also available as special accessories.

8.2.2 Removing the transport lock Pull the hose (1) off the shaft (2).

8.2.3

Machine supplied without mounting hardware

002BA104 KN

002BA266 KN

002BA330 KN

Shut off the engine. Lay your power tool on its back so that the cut-
ting attachment mounting face is pointing up.

8.2 Mounting Hardware for Cutting Attachments

The mounting hardware supplied depends on the cutting attachment that comes as original equip- ment with the new machine.

8.2.1

Machine supplied with mounting hard- ware

Mowing heads and metal cutting attachments may be mounted.

2
Only mowing heads may be used which mount directly to the shaft (2).
8.3 Blocking the Shaft
2

3
4 5
1 2

7

6

6

The output shaft (2) must be blocked with the stop pin (6) or screwdriver (6) to mount or remove cutting attachments. These parts come standard with the machine or are available as special accessories. Insert the stop pin (6) or screwdriver (6) in the
hole (7) in the gearbox as far as stop ­ and apply slight pressure. Rotate shaft, nut or cutting attachment until the stop pin slips into position and blocks the shaft.

002BA164 KN

16

0458-826-0121-B

271BA057 KN 002BA385 KN

8 Mounting the Cutting Attachment
8.4 Removing the Mounting Hard- ware

English

1

1 2
3
4 5

Block the shaft. Use the combination wrench (1) to loosen and
remove the nut (2) clockwise (left-hand thread). Take the thrust washer (3) off the shaft (4). Do not remove the thrust plate (5).
8.5 Mounting the Cutting Attach- ment
WARNING
Use a deflector that matches the cutting attach- ment ­ see “Mounting the Deflector”.
8.6 Fitting the mowing head with screw mounting
Keep the supplement sheet for the mowing head in a safe place.

Fit the thrust plate Turn the mowing head anticlockwise on the
shaft (1) as far as it will go Retain the shaft Tighten the mowing head
NOTICE
Remove the tool that was used to block the shaft.
8.7 Removing the Mowing Head
Retain the shaft Turn the mowing head clockwise
8.8 Mounting Metal Cutting Attach- ment
WARNING
Wear protective gloves to reduce the risk of direct contact with the sharp cutting edges. Mount only metal cutting attachments.

0458-826-0121-B

17

English

9 Fuel

Check direction of rotation of cutting attachment

1

2

3

The cutting edges of the grass cutting blades (1) and (2) may point in either direction ­ these cut- ting attachments must be turned over regularly to reduce one-sided wear.
Cutting edges of grass cutting blade (3) must point clockwise.
WARNING
Direction of rotation is indicated by an arrow on the inside of the deflector.

9

7

6

8

4

5

Place the cutting attachment (4) on the thrust plate (5).
WARNING
Collar (see arrow) must engage the cutting attachment’s mounting hole.

681BA051 KN

681BA121 KN

Securing the cutting attachment Fit the thrust washer (6) ­ convex side must
face up. Fit the rider plate (7). Block the shaft (8). Use the combination wrench (14) to screw the
mounting nut (9) on to the output shaft coun- terclockwise and tighten it down firmly.
WARNING
If the mounting nut has become too loose, fit a new one.
NOTICE
Remove the tool used to block the shaft.
8.9 Removing the Metal Cutting Attachment
WARNING
Wear protective gloves to reduce the risk of direct contact with the sharp cutting edges. Block the shaft. Unscrew the mounting nut clockwise. Remove cutting attachment and its mounting
hardware from the gearbox ­ but do not remove the thrust plate (5).
9 Fuel
The engine requires a mixture of gasoline and engine oil.
WARNING
Avoid direct skin contact with fuel and breathing in of gasoline fumes.
9.1 STIHL MotoMix
STIHL recommends using STIHL MotoMix. This pre-blended fuel is free of benzene and lead, is distinguished by a high octane rating, and always provides the proper mixing ratio. STIHL MotoMix uses STIHL HP Ultra two-stroke engine oil for optimum engine life. MotoMix is not available in all markets.

18

0458-826-0121-B

10 Fueling
9.2 Mixing fuel

NOTICE

Unsuitable fuels or a mixing ratio that deviates from the specification can lead to severe engine damage. The engine, seals, fuel lines and fuel tank may be damaged if low-quality gasoline or engine oil is used.

9.2.1 Gasoline

Use only high-quality gasoline with an octane rat- ing of at least 90 ROC ­ leaded or unleaded.

Gasoline with an alcohol component exceeding 10% can cause impaired engine performance in engines with manually adjustable carburetors and thus should not be used in these engines.

Engines with M-Tronic deliver full engine per- formance using gasoline with an alcohol compo- nent of up to 27% (E27).

9.2.2 Engine oil

If you mix the fuel yourself, use only STIHL twostroke engine oil or another high-performance engine oil classified as JASO FB, JASO FC, JASO FD, ISO-L-EGB, ISO-L-EGC or ISO-LEGD.

STIHL specifies STIHL HP Ultra two-stroke engine oil or an equivalent high- performance engine oil in order to maintain emission limits over the machine’s service life.

9.2.3 Mixing ratio

with STIHL two-stroke engine oil 1:50; 1:50 = 1 part oil + 50 parts gasoline

9.2.4 Examples

Quantity of gaso- STIHL two-stroke

line

engine oil 1:50

Liters

Liters

(ml)

1

0.02

(20)

5

0.10

(100)

10

0.20

(200)

15

0.30

(300)

20

0.40

(400)

25

0.50

(500)

Pour oil into an approved safety fuel canister first, then add gasoline and mix thoroughly

9.3 Storing fuel mixture

Store in approved safety fuel canisters only in a dry, cool and secure place protected against light and sunlight.

English
Fuel mixture deteriorates with age ­ mix only as much as needed for a few weeks. Do not store fuel mixture for longer than 30 days. The fuel mixture can become unusable more quickly if exposed to light, sunlight or low or high tempera- tures. STIHL MotoMix however can be stored for up to 5 years without any problems. Shake the canister containing the fuel mixture
thoroughly before refueling
WARNING Pressure may have built up in the canister ­ open it carefully. The fuel tank and the canister in which fuel
mixture is stored should be cleaned thoroughly from time to time Residual fuel and the liquid used for cleaning must be disposed of in accordance with regula- tions and without harming the environment!
10 Fueling
Before fueling, clean the filler cap and the area around it to ensure that no dirt falls into the tank.
Position the machine so that the filler cap is facing up.
Open the filler cap. Take care not to spill fuel while fueling and do not overfill the tank. STIHL recommends you use the STIHL filler nozzle (special accessory).

232BA046 KN

0458-826-0121-B

19

English
WARNING
After fueling, tighten down the filler cap as securely as possible by hand.
11 Fitting the Harness
The type and style of the harness depend on the market. The use of the harness is described in the chap- ter on “Approved Combinations of Cutting Attachment, Deflector, Handle and Harness”.
11.1 Shoulder strap

11.2

11 Fitting the Harness
Full Harness

1 3

2

002BA228 KN

Put on the shoulder strap (1). Adjust the length of the strap so that the cara-
biner (2) is about a hand’s width below your right hip. Balance the machine.

Put on the harness (1) and close the locking plate (3).
Adjust the length of the strap ­ with the machine attached, the carabiner (2) must be about a hand’s width below your right hip.
Balance the machine ­ see “Balancing the Machine”.
12 Balancing the Machine
The type and style of the harness and carabiner (spring hook) depend on the market.
The carrying ring is integrated in the control han- dle on loop-handled units­ see “Main Parts”. Loop-handled units do not need to be balanced.
12.1 Attaching the unit to the har- ness

2 1
1 2

20

0458-826-0121-B

002BA311 KN

13 Starting / Stopping the Engine
Attach the carabiner (1) to the carrying ring (2) on the drive tube.

12.3

English
Detaching the unit from the harness

002BA312 KN

Loosen the screw (3).
12.2 Floating position

1

1

2

2

Press down the bar on the carabiner (1) and pull the carrying ring (2) out of the carabiner.
13 Starting / Stopping the Engine
13.1 Version with bike handle
13.1.1 Controls
6 54

3

7

STOP

002BA313 KN 233BA037 KN

2

Mowing heads and grass cutting blades should just touch the ground.
Proceed as follows to adjust the floating position: Move the carrying ring up or down the drive
tube ­ tighten the screw moderately ­ let the unit go and wait until is its balanced ­ then check the floating position.
When the correct floating position has been reached: Tighten down the screw on the carrying ring
firmly.

1
1 Throttle trigger lockout 2 Throttle trigger 3 Slide control 13.1.2 Positions of slide control 4 START ­ ignition is switched on ­ the engine
can start

0458-826-0121-B

21

English
5 F ­ normal run position ­ the engine is running or can start
6 STOP0 ­ engine off ­ the ignition is switched off
13.1.3 Symbol on slide control
7 h ­ stop symbol and arrow. To stop the engine, push the slide control in the direction of the arrow on the stop symbol (h) to STOP0.
13.1.4 Starting Press down the trigger lockout lever and
squeeze the throttle trigger and hold them in that position. Move the slide control to START and hold it
there. Now release the throttle trigger, slide control
and trigger lockout in that order. This is the starting throttle position. Go to “All versions”.
13.2 Version with loop handle
13.2.1 Controls

13 Starting / Stopping the Engine Positions of stop switch 6 I ­ normal run position ­ the engine can start
or is running 7 0 ­ Stop ­ engine off ­ the ignition is switched
off 13.2.2 Starting
4

233BA048 KN 233BA049 KN

71 6
2
3 54
1 Stop switch 2 Throttle trigger lockout 3 Throttle trigger 4 Tongue of throttle trigger 5 Catch 22

Move the stop switch to I. Press down the throttle trigger lockout and
hold it there. Squeeze the throttle trigger until the catch on
the tongue (4) can be engaged on the hous- ing. Now release the throttle trigger, tongue and trigger lockout in that order. This is the starting throttle position. Go to “All versions”.
0458-826-0121-B

13 Starting / Stopping the Engine
13.3 All models
9 8

English
Put the unit on the ground: It must rest securely on the engine support and the deflec- tor.
If fitted: Remove the transport guard from the cutting attachment.
To reduce the risk of accidents, check that the cutting attachment is not touching the ground of any other obstacles. Make sure you have a firm footing, either
standing, stooping or kneeling. Hold the unit firmly on the ground with your left
hand and press down ­ do not touch the throt- tle trigger, lockout lever or stop switch.
NOTICE
Do not stand or kneel on the drive tube.

232BA011 KN

Set the choke lever (8) to g if the engine is cold e for warm start ­ also use this position if the
engine has been running but is still cold. Press the manual fuel pump bulb (9) at least
five times ­ even if the bulb is filled with fuel.
13.3.1 Cranking

232BA014 KN

233BA020 KN

0458-826-0121-B

233BA014 KN

Hold the starter grip with your right hand. 13.3.2 Version without ErgoStart Pull the starter grip slowly until you feel it
engage and then give it a brisk strong pull.
NOTICE
Do not pull out the starter rope all the way ­ it might otherwise break.
13.3.3 Version with ErgoStart Pull the starter grip slowly until you feel it
engage and then pull it out slowly and steadily.
23

232TI015 KN
681BA268 KN

English
NOTICE
Do not pull out the starter rope all the way ­ it might otherwise break.
13.3.4 Both versions Do not let the starter grip snap back. Guide it
slowly back into the housing so that the starter rope can rewind properly. Continue cranking. 13.3.5 When engine begins to fire
8
After no more than five pulls, move the choke lever (8) to e.
continue cranking. 13.3.6 As soon as the engine runs Version with bike handle Blip the throttle trigger ­ the engine settles
down to idle speed. Version with loop handle Squeeze the throttle trigger to disengage the
tongue ­ the engine will settle down to idle speed. Your machine is now ready for operation.
WARNING
Make sure the carburetor is correctly adjusted. The cutting attachment must not rotate when the engine is idling.
13.4 Stopping the Engine
Move the slide control in direction of the arrow (h) to STOP-0 or the stop switch to STOP / 0.
13.5 If engine does not start
Choke lever If you did not move the choke lever to e quickly enough after the engine began to fire, the com- bustion chamber is flooded.

Transporting the Unit
Set the choke lever to e . Set the slide control, trigger lockout lever and
throttle trigger to the starting throttle position. Start the engine by pulling the starter rope
briskly ­ 10 to 20 pulls may be necessary.
13.5.1 If the engine still does not start Move the slide control or stop switch
to STOP / 0. Remove the spark plug ­ see “Spark Plug”. Dry the spark plug. Crank the engine several times with the starter
to clear the combustion chamber. Refit the spark plug ­ see “Spark Plug”. Move the slide control or stop switch to F / I. Set the choke lever to e ­ even if the engine
is cold. Now start the engine.
13.5.2 Fuel tank run until completely dry After refueling, press the manual fuel pump
bulb at least five times ­ even if the bulb is fil- led with fuel. Set the choke lever to suit the engine temper- ature. Now start the engine.
14 Transporting the Unit
14.1 Using transport guard
The type of transport guard depends on the metal cutting attachment supplied with the machine. Transport guards are available as spe- cial accessories.
14.1.1 230 mm Grass Cutting Blades

24

0458-826-0121-B

Operating Instructions

681BA269 KN

English
15.3 After Finishing Work
Storing for a short period: Wait for the engine to cool down. Empty the fuel tank and keep the machine in a dry place, well away from sources of ignition, until you need it again. For longer outof-service periods ­ see “Storing the Machine”.
16 Cleaning the Air Filter
16.1 If there is a noticeable loss of engine power

681BA270 KN

2 1

232BA017 KN

681BA272 KN

15 Operating Instructions
15.1 During break-in period
A factory-new machine should not be run at high revs (full throttle off load) for the first three tank fillings. This avoids unnecessary high loads dur- ing the break-in period. As all moving parts have to bed in during the break-in period, the frictional resistances in the engine are greater during this period. The engine develops its maximum power after about 5 to 15 tank fillings.
15.2 During Operation
After a long period of full throttle operation, allow the engine to run for a short while at idle speed so that engine heat can be dissipated by the flow of cooling air. This protects engine-mounted components (ignition, carburetor) from thermal overload.

Set the choke lever to g. Press in the tab (1) and swing the filter
cover (2) down. Clean away loose dirt from around the filter.

0458-826-0121-B

25

232BA018 KN
233BA071 KN

English

17 Adjusting the Carburetor
17.4 Identifying the Carburetor
Use the following illustrations to identify the carburetor installed in your machine and then adjust the carburetor as described:

1

2

H

L

H

L

4

LA

LA

3
Remove the felt element (3) from the filter housing (4) and replace it ­ knock out or blow out as a temporary measure ­ do not wash.
Replace damaged parts. Fit the felt element (3) in the filter housing (4). Close the filter cover so that it snaps into posi-
tion.

Adjusting the Carburetor

General Information
The carburetor comes from the factory with a standard setting. This setting provides an optimum fuel-air mixture under most operating conditions.
17.2 Preparations
Shut off the engine. Mount the cutting attachment. Check the air filter and clean or replace if nec-
essary. Check the spark arresting screen (not in all
models, country-specific) in the muffler and clean or replace if necessary.
17.3 Different Standard Settings
Different carburetors are installed at the factory. A different standard setting is necessary for each of these carburetors.

17.4.1 Carburetor 1 2-MIX carburetor with limiter caps on high speed screw (H) and low speed screw (L), and marked “2-MIX” 17.4.2 Carburetor 2 Carburetor without limiter caps on high speed screw (H) and low speed screw (L)
17.5 Standard Setting on Carbu- retor 1
L
Turn high speed screw (H) counterclockwise as far as stop (no more than 3/4 turn).

233BA070 KN

26

0458-826-0121-B

17 Adjusting the Carburetor Turn the low speed screw (L) carefully clock-
wise until it is against its seat, then it back it off a 3/4 turn.
17.6 Standard Setting on Carbu- retor 2
L
Turn the high speed screw (H) carefully clock- wise until it is against its seat, then turn it back 2 full turns.
Turn the low speed screw (L) carefully clock- wise until it is against its seat, then turn it back 1 1/2 turns.
17.7 Adjusting Idle Speed
Carry out the standard setting. Start and warm up the engine. 17.7.1 Engine stops while idling Turn the idle speed screw (LA) slowly clock-
wise until the engine runs smoothly ­ the cut- ting attachment must not rotate. 17.7.2 Cutting attachment rotates when
engine is idling Turn the idle speed screw (LA) counterclock-
wise until the cutting attachment stops moving and then turn the screw another 1/2 to 1 full turn in the same direction.

233BA069 KN

English

WARNING

If the cutting attachment continues to rotate when the engine is idling, have your machine checked and repaired by your servicing dealer.

17.7.3

Erratic idling behavior, poor accelera- tion (despite correction to setting of LA screw).

Idle setting is too lean

Carburetor 1 Turn the low speed screw (L) carefully coun-
terclockwise, no further than stop, until the engine runs smoothly and still accelerates sat- isfactorily.

Carburetor 2 Rotate the low speed screw (L) slowly
about 1/4 turn counterclockwise until the engine runs smoothly and still accelerates sat- isfactorily.

Erratic idling behavior

Idle setting is too rich

Carburetor 1 Turn the low speed screw (L) slowly clock-
wise, no further than stop, until the engine runs smoothly and still accelerates satisfacto- rily.

Carburetor 2 Rotate the low speed screw (L) slowly
about 1/4 turn clockwise until the engine runs smoothly and still accelerates satisfactorily.

It is usually necessary to change the setting of the idle speed screw (LA) after every correction to the low speed screw (L).

17.8 Fine Tuning for Operation at High Altitude

A slight correction of the setting may be neces- sary if engine does not run satisfactorily:

Carburetor 1 Carry out the standard setting. Warm up the engine. Turn high speed screw (H) slightly clockwise
(leaner) ­ no further than stop.

Carburetor 2 Carry out the standard setting. Warm up the engine. Turn high speed screw (H) slightly clockwise
(leaner) ­ no more than a 3/4 turn.

0458-826-0121-B

27

English
NOTICE After returning from high altitude, reset the car- buretor to the standard setting. If the setting is too lean there is a risk of engine damage due to insufficient lubrication and over- heating.
18 Spark Plug
If the engine is down on power, difficult to start or runs poorly at idle speed, first check the spark plug.
Fit a new spark plug after about 100 operating hours ­ or sooner if the electrodes are badly eroded. Install only suppressed spark plugs of the type approved by STIHL ­ see “Specifica- tions”.
18.1 Removing the Spark Plug
Move the stop switch to 0.
1
Pull off the spark plug boot (1). Unscrew the spark plug.
18.2 Checking the Spark Plug
A
Clean dirty spark plug. Check electrode gap (A) and readjust if neces-
sary ­ see “Specifications”. Rectify the problems which have caused foul-
ing of the spark plug. Possible causes are: ­ Too much oil in fuel mix.
28

000BA039 KN

232BA081 KN

18 Spark Plug
­ Dirty air filter. ­ Unfavorable running conditions.
1
WARNING
Arcing may occur if the adapter nut (1) is loose or missing. Working in an easily combustible or explosive atmosphere may cause a fire or an explosion. This can result result in serious inju- ries or damage to property. Use resistor type spark plugs with a properly
tightened adapter nut.
18.3 Installing the spark plug
Screw home the spark plug, fit the boot and press it down firmly.
19 Engine Running Behavior
If engine running behavior is unsatisfactory even though the air filter is clean and the carburetor is properly adjusted, the cause may be the muffler. Have the muffler checked for contamination (car- bonization) by your servicing dealer. STIHL recommends that you have servicing and repair work carried out exclusively by an author- ized STIHL servicing dealer.
20 Storing the Machine
If out of use for periods of about 30 days or lon- ger Drain and clean the fuel tank in a well ventila-
ted area. Dispose of fuel properly in accordance with
local environmental requirements. If a manual fuel pump is fitted: Press the man-
ual fuel pump at least 5 times. Start the engine and run it at idling speed until
it stops. Remove, clean and inspect the cutting attach-
ment. Coat metal cutting attachments with cor- rosion inhibitor. Thoroughly clean the machine ­ pay special attention to the cylinder fins and air filter.
0458-826-0121-B

000BA045 KN

21 Sharpening Metal Cutting Blades
Store the machine in a dry and secure location ­ out of the reach of children and other unau- thorized persons.
21 Sharpening Metal Cutting Blades
Use a sharpening file (special accessory) to sharpen dull cutting attachments. In case of more serious wear or nicks: Resharpen with a grinder or have the work done by a dealer ­ STIHL recommends a STIHL servicing dealer.
Sharpen frequently, take away as little metal as possible ­ two or three strokes of the file are usually enough.

English
22 Maintaining the Mowing Head
22.1 Placing power tool on the ground

002BA113 KN 002BA104 KN

1

1

1

2

2

2

Resharpen the teeth (1) uniformly ­ do not alter the contour of the parent blade (2) in any way.
See cutting attachment packaging for additional sharpening instructions. Keep the packaging for future reference.
21.1 Balancing
After resharpening about 5 times, check the cutting attachment for out-of- balance on a STIHL balancer (special accessory) or have it checked by a dealer and re-balanced as nec- essary ­ STIHL recommends a STIHL servic- ing dealer.

Shut off the engine. Lay your power tool on its back so that the cut-
ting attachment mounting face is pointing up.
22.2 Replacing Nylon Line
Always check the mowing head for signs of wear before replacing the nylon line.
WARNING
If there are signs of serious wear, replace the complete mowing head.
The nylon mowing line is referred to as “nylon line” or “line” in the following.
The mowing head is supplied with illustrated instructions for replacing the nylon line. Keep the instructions for the mowing head in a safe place. If necessary, remove the mowing head.
22.3 Adjusting Nylon Line
STIHL SuperCut
Fresh line is advanced automatically if the remaining line is at least 6 cm (2 1/2 in) long. The blade on the deflector trims overlong lines to the correct length.
STIHL AutoCut With the engine running, hold the rotating
mowing head above the grass surface. Tap it on the ground once ­ fresh line is
advanced and the blade on the deflector trims it to the right length.
Fresh line is advanced every time the mowing head is tapped on the ground. For this reason observe the mowing head’s cutting performance during operation. If the mowing head is tapped

0458-826-0121-B

29

English
on the ground too often, the line limiting blade will unnecessarily cut off unused lengths of nylon line. Line feed operates only if both lines are still at least 2.5 cm (1 in) long.
STIHL TrimCut
WARNING
To reduce the risk of injury, always shut off the engine before adjusting the nylon line by hand. Pull the spool up ­ rotate it about 1/6 turn
counterclockwise until it engages ­ and allow it to spring back. Pull ends of the lines outward. Repeat the above procedure as necessary until both lines reach the limiter blade on the deflec- tor. Rotating the spool from one stop to the next advances about 4 cm (1 1/2 in) of fresh line.
22.4 Replacing Nylon Line
STIHL PolyCut Precut lengths of nylon line can be fitted to the PolyCut in place of the cutting blades.
STIHL DuroCut, STIHL PolyCut
WARNING
To reduce the risk of injury, always shut off the engine before refilling the mowing head. Fit precut lengths of nylon line in the mowing
head as described in the instructions supplied.
22.5 Replacing Cutting Blades
22.5.1 STIHL PolyCut Always check the mowing head for signs of wear before installing new cutting blades.

23 Inspections and Maintenance by Dealer
WARNING
If there are signs of serious wear, replace the complete mowing head.
The thermoplastic cutting blades are referred to as “blades” in the following. The mowing head is supplied with illustrated instructions for replacing the blades. Keep the instructions for the mowing head in a safe place.
WARNING
To reduce the risk of injury, always shut off the engine before installing the blades. Remove the mowing head. Replace blades as shown in the illustrated
instructions. Mount the mowing head on the machine.
23 Inspections and Mainte- nance by Dealer
23.1 Maintenance Work
STIHL recommends that you have servicing and repair work carried out exclusively by an author- ized STIHL servicing dealer.
23.2 Fuel Pickup Body in Tank
Have the pickup body in the fuel tank replaced every year.

30

0458-826-0121-B

before starting work after finishing work or daily
after each refueling stop weekly monthly
every 12 months if problem
if damaged as required

Maintenance and Care

Maintenance and Care
The following intervals apply to normal operating conditions only. If your daily working time is longer or operating conditions are difficult (very dusty work area, etc.), shorten the specified intervals accord- ingly.

English

Complete machine

Visual inspection (condi- X

X

tion, leaks)

Clean

X

Control handle

Check operation

X

X

Air filter

Clean

Replace

Manual fuel pump (if fit- ted)

Check

X

Have repaired by servic- ing dealer1)

Pickup body (filter) in fuel Check

tank

Have replaced by serv-

icing dealer1)

Fuel tank

Clean

Carburetor

Check idle adjustment ­ X

X

the cutting attachment

must not rotate

Readjust idle speed

Spark plug

Readjust electrode gap

Replace after every 100 operating hours

Cooling air inlet

Visual inspection

X

Clean

Spark arrestor2) in muffler Have checked by servic-

X

ing dealer1)

Have cleaned or replaced by servicing dealer1)

All accessible screws and Retighten nuts (not adjusting screws)

Cutting attachment

Visual inspection

X

X

Replace

Check tightness

X

X

Metal Cutting Attachment Sharpen

X

Safety labels

Replace

1)STIHL recommends an authorized STIHL servicing dealer. 2)not in all versions, market-specific

0458-826-0121-B

X

X

X

X

X

X

XX

X

X

X X

X X
XX
X
X X
X

31

English
25 Minimize Wear and Avoid Damage
Observing the instructions in this manual helps reduce the risk of unnecessary wear and dam- age to the power tool.
The power tool must be operated, maintained and stored with the due care and attention described in this owner’s manual.
The user is responsible for all damage caused by non-observance of the safety precautions, oper- ating and maintenance instructions in this man- ual. This includes in particular: ­ Alterations or modifications to the product not
approved by STIHL. ­ Using tools or accessories which are neither
approved or suitable for the product or are of a poor quality. ­ Using the product for purposes for which it was not designed. ­ Using the product for sports or competitive events. ­ Consequential damage caused by continuing to use the product with defective components.
25.1 Maintenance Work
All the operations described in the “Maintenance Chart” must be performed on a regular basis. If these maintenance operations cannot be per- formed by the owner, they should be performed by a servicing dealer.
STIHL recommends that you have servicing and repair work carried out exclusively by an author- ized STIHL servicing dealer. STIHL dealers are regularly given the opportunity to attend training courses and are supplied with the necessary technical information.
If these maintenance operations are not carried out as specified, the user assumes responsibility for any damage that may occur. Among other parts, this includes: ­ Damage to the engine due to neglect or defi-
cient maintenance (e.g. air and fuel filters), incorrect carburetor adjustment or inadequate cleaning of cooling air inlets (intake ports, cyl- inder fins). ­ Corrosion and other consequential damage resulting from improper storage. ­ Damage to the machine resulting from the use of poor quality replacement parts.

25 Minimize Wear and Avoid Damage
25.2 Parts Subject to Wear and Tear
Some parts of the power tool are subject to nor- mal wear and tear even during regular operation in accordance with instructions and, depending on the type and duration of use, have to be replaced in good time. Among other parts, this includes: ­ Cutting attachments (all types) ­ Mounting hardware for cutting attachments
(rider plate, nut, etc.) ­ Deflectors for cutting attachments ­ Clutch ­ Filters (air, fuel) ­ Rewind starter ­ Spark plug
26 Main Parts

7

6

8

3

1

4

2

9 20

11 12

10

18 20 19

11 21 8

5
15 13
14

16

17

6

1 Manual fuel pump 2 Carburetor adjusting screws 3 Spark plug boot 4 Starter grip 5 Muffler (with spark arrestor in some markets) 6 Throttle trigger 7 Slide control 8 Throttle trigger lockout 9 Bike handle (handlebar) 10 Handle support 11 Carrying ring 12 Throttle cable retainer 13 Choke lever 14 Air filter cover 15 Tank cap

233BA076 KN

32

0458-826-0121-B

27 Specifications
16 Tank 17 Machine support 18 Loop handle 19 Barrier bar (country specific) 20 Drive tube 21 Stop switch # Serial number

2

1

3

5

4

1 Mowing head 2 Deflector for mowing heads only 3 Blade 4 Deflector for grass cutting blades only 5 Grass cutting blade

27 Specifications

27.1 Engine

Single-cylinder two-stroke engine

27.1.1 FS 55

Displacement:

27.2cm3

Cylinder bore:

34 mm

Piston stroke:

30 mm

Engine power to ISO 8893: 0.75 kW (1 hp) at

7000 1/min

Idle speed:

2800 rpm

Cut-off speed (nominal 9500 rpm

value):

0458-826-0121-B

002BA270 KN

English

Max. output shaft speed 7700 rpm (cutting attachment):

27.1.2 FS 55 2-MIX

Displacement:

27.2cm3

Cylinder bore:

34 mm

Piston stroke:

30 mm

Engine power to ISO 8893: 0.75 kW (1.0 hp) at

8500 1/min

Idle speed:

2800 rpm

Cut-off speed (nominal 10000 rpm

value):

Max. output shaft speed 8100 rpm

(cutting attachment):

27.2 Ignition system

Electronic magneto ignition

Spark plug (suppressed): Bosch WSR 6 F,

NGK BPMR 7 A,

STIHL ZK C 14

Electrode gap:

0.5 mm

27.3 Fuel system

All-position diaphragm carburetor with integral fuel pump

Fuel tank capacity:

330 cm3 (0.33 l)

27.4 Weight

Dry, without cutting attachment and deflector

FS 55:

5.0 kg

FS 55 2-MIX:

5.1 kg

FS 55 C:

with ErgoStart: 5.2 kg

FS 55 R:

4.8 kg

FS 55 R 2-MIX:

4.9 kg

FS 55 RC:

with ErgoStart: 5.0 kg

27.5 Sound and Vibration Levels

The idle speed and nominal maximum speed are equally taken into account when calculating the sound and vibration levels.

For further details on compliance with Vibration Directive 2002/44/EC, see

www.stihl.com/vib

27.5.1

Sound pressure level Lpeq in accord- ance with ISO 22868

with mowing head FS 55 with bike handle: FS 55 R: with metal mowing tool FS 55 with bike handle: FS 55 R with barrier bar:

95 dB(A) 95 dB(A) 94 dB(A) 94 dB(A)

27.5.2

Sound power level Lw in accordance with ISO 22868

with mowing head FS 55 with bike handle:

108 dB(A)

33

English

FS 55 R: with metal mowing tool FS 55 with bike handle: FS 55 R with barrier bar:

108 dB(A) 107 dB(A) 107 dB(A)

27.5.3

Vibration level ahv,eq in accordance with ISO 22867

with mowing head FS 55 with bike han- dle: FS 55 R:

Handle, left Handle, right
5.5 m/s2 5.5 m/s2 8.5 m/s2 8.5 m/s2

with metal mowing tool Handle, left Handle, right
FS 55 with bike han- 6.8 m/s2 5.6 m/s2 dle: FS 55 R with barrier 8.0 m/s2 9.0 m/s2 bar:
The Kfactor in accordance with Directive 2006/42/EC is 2.0 dB(A) for the sound pressure level and sound power level; the Kfactor in accordance with Directive 2006/42/EC is 2.0 m/s2 for the vibration level.

27.6 REACH

REACH is an EC regulation and stands for the Registration, Evaluation, Authorization and Restriction of Chemical substances.

For information on compliance with the REACH regulation (EC) No. 1907/2006 see

www.stihl.com/reach

27.7 Exhaust Emissions

The CO2 value measured in the EU type appro- val procedure is specified at

www.stihl.com/co2
in the product-specific technical data.
The measured CO2 value was determined on a representative engine in accordance with a standardized test procedure under laboratory conditions and does not represent either an explicit or implied guarantee of the performance of a specific engine.
The applicable exhaust emission requirements are fulfilled by the intended usage and mainte- nance described in this User Manual. The oper- ating license shall be void if the engine is modi- fied in any way.

28 Maintenance and Repairs
Users of this machine may only carry out the maintenance and service work described in this

34

28 Maintenance and Repairs
user manual. All other repairs must be carried out by a servicing dealer.
STIHL recommends that you have servicing and repair work carried out exclusively by an author- ized STIHL servicing dealer. STIHL dealers are regularly given the opportunity to attend training courses and are supplied with the necessary technical information.
When repairing the machine, only use replace- ment parts which have been approved by STIHL for this power tool or are technically identical. Only use high-quality replacement parts in order to avoid the risk of accidents and damage to the machine.
STIHL recommends the use of original STIHL replacement parts.
Original STIHL parts can be identified by the STIHL part number, the { logo and the STIHL parts symbol K (the symbol may appear alone on small parts).
29 Disposal
Contact the local authorities or your STIHL serv- icing dealer for information on disposal.
Improper disposal can be harmful to health and pollute the environment.

Take STIHL products including packaging to a suitable collection point for recycling in accord- ance with local regulations.
Do not dispose with domestic waste.

EC Declaration of Conformity

ANDREAS STIHL AG & Co. KG Badstr. 115 D-71336 Waiblingen
Germany

declare under our sole responsibility that

Designation:

Brushcutter

0458-826-0121-B

000BA073 KN

30 EC Declaration of Conformity

Make: Series: Serial identification number: Displacement:

STIHL FS 55 FS 55 C FS 55 C-E FS 55 R FS 55 RC FS 55 RC-E 4140 27.2 cm3

conforms to the relevant provisions of Directives 2011/65/EU, 2006/42/EC, 2014/30/EU and 2000/14/EC and has been developed and manu- factured in compliance with the following stand- ards in the versions valid on the date of produc- tion:

EN ISO 11806-1, EN 55012, EN 6100061

The measured and the guaranteed sound power level have been determined in accordance with Directive 2000/14/EC, Annex V, and standard ISO 10884.

Measured sound power level 108 dB(A)

Guaranteed sound power level 110 dB(A)
Technical documents deposited at: ANDREAS STIHL AG & Co. KG Produktzulassung (Product Licensing) The year of manufacture and serial number are applied to the product. Done at Waiblingen, 03.02.2020 ANDREAS STIHL AG & Co. KG pp

Dr. Jürgen Hoffmann
Director Product Certification & Regulatory Affairs

0458-826-0121-B

English 35

www.stihl.com

04588260121B
0458-826-0121-B

04588260121B
0458-826-0121-B

References

• Country Routing Page: Welcome to STIHL | STIHL
• Information on Physical Agents Directive Vibration | STIHL | STIHL
• Country Routing Page: Welcome to STIHL | STIHL

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