Stihl FB 131 Instruction Manual
STIHL FB 131
WARNING
Read Instruction Manual thoroughly
before use and follow all safety
precautions – improper use can
cause serious or fatal injury.
ADVERTENCIA
Antes de usar la máquina lea y siga
todas las precauciones de
seguridad dadas en el manual de
instrucciones – el uso incorrecto
puede causar lesiones graves o
mortales.
{
Instruction Manual
Manual de instrucciones
Instruction Manual
1 - 36
Manual de instrucciones
37 - 77
Contents
English
Guide to Using this Manual 2
Safety Precautions and Working
Techniques 3
Using the Unit 12
Approved Power Tool Attachments 13
Approved Cutting Attachments 14
Mounting the Loop Handle 14
Adjusting the Throttle Cable 15
Original Instruction ManualPrinted on chlorine-free paper
Fuel 15
Fueling 16
Starting / Stopping the Engine 17
Operating Instructions 19
Replacing the Air Filter 19
Engine Management 20
Adjusting the Carburetor 20
Spark Arresting Screen in Muffler 20
Spark Plug 21
Storing the Machine 22
Replacing the Depth Wheel 22
Replacing the Skirt 23
Replacing the Cutting Blade 23
Checking and Replacing the Wear
Printing inks contain vegetable oils, paper can be recycled.
Guard 24
Maintenance and Care 26
Main Parts 28
Specifications 29
Maintenance and Repairs 30
Disposal 30
Limited Warranty 31
STIHL Incorporated Federal
Emission Control Warranty
Statement 32
STIHL Incorporated California
Exhaust and Evaporative
Emissions Control Warranty
Statement 34
Trademarks 36
Allow only persons who fully understand
this manual to operate your bed
redefiner.
To receive maximum performance and
satisfaction from your STIHL bed
redefiner, it is important that you read,
understand and follow the safety
precautions and the operating and
maintenance instructions in chapter
"Safety Precautions and Working
Techniques" before using your bed
redefiner. For further information you
can go to www.stihlusa.com.
Contact your STIHL dealer or the STIHL
distributor for your area if you do not
understand any of the instructions in this
manual.
WARNING
Because a bed redefiner is a high-speed
cutting tool some special safety
precautions must be observed to reduce
the risk of personal injury. Careless or
improper use may cause serious or even
fatal injury.
{
© ANDREAS STIHL AG & Co. KG, 2017
0458-488-8621-A. VA2.L17.
0000007388_006_GB
FB 131
This instruction manual is protected by copyright. All rights reserved, especially the rights to reproduce, translate and process
with electronic systems.
1
English
Guide to Using this Manual
Pictograms
The meanings of the pictograms
attached to or embossed on the
machine are explained in this manual.
Depending on the model concerned, the
following pictograms may be on your
machine.
Fuel tank for gasoline
and engine oil mixture
Press to operate decompression valve
Manual fuel pump
Press to operate manual
fuel pump
Symbols in Text
Many operating and safety instructions
are supported by illustrations.
The individual steps or procedures
described in the manual may be marked
in different ways:
N A bullet marks a step or procedure.
A description of a step or procedure that
refers directly to an illustration may
contain item numbers that appear in the
illustration. Example:
N Loosen the screw (1).
N Lever (2) ...
In addition to the operating instructions,
this manual may contain paragraphs
that require your special attention. Such
paragraphs are marked with the
symbols and signal words described
below:
DANGER
Indicates a hazardous situation that, if
not avoided, will result in death or
serious injury.
Engineering Improvements
STIHL’s philosophy is to continually
improve all of its products. As a result,
engineering changes and improvements
are made from time to time. Therefore,
some changes, modifications and
improvements may not be covered in
this manual. If the operating
characteristics or the appearance of
your machine differs from those
described in this manual, please contact
your STIHL dealer or the STIHL
distributor for your area for assistance.
Filler hole for gear
lubricant
Air intake summer mode
WARNING
Indicates a hazardous situation that, if
not avoided, could result in death or
serious injury.
NOTICE
Air intake winter mode
Handle heating
2
Indicates a risk of property damage,
including damage to the machine or its
individual components.
FB 131
English
Safety Precautions and
Working Techniques
Because a bed redefiner
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, fully understand
and observe the following
safety precautions and
warnings. Read the
instruction manual and
the safety precautions
periodically. Careless or
improper use may cause
serious or fatal injury.
WARNING
As more fully explained later in these
Safety Precautions, to reduce the risk of
personal injury, make sure your unit is
equipped with the proper deflector, skirt
and handle. Use only cutting
attachments that are specifically
authorized by STIHL for use on your FB
model.
Have your STIHL dealer show you how
to operate your power tool. Observe all
applicable local safety regulations,
standards and ordinances.
WARNING
Do not lend or rent your power tool
without the instruction manual. Be sure
that anyone using it understands the
information contained in this manual.
WARNING
The use of this machine may be
hazardous. If the rotating blade comes in
contact with your body, it will cut you.
When it comes in contact with solid
foreign objects such as rocks or bits of
metal, it may fling them directly or by
ricochet in the direction of bystanders or
the operator. Striking such objects could
damage the cutting attachment and may
cause blades to crack, chip or break.
Thrown objects, including broken
blades, may result in serious or fatal
injury to the operator or bystanders.
Do not use the bed redefiner on hard
ground or wet soil. Use your bed
redefiner only for redefining existing
flower bed edges.
WARNING
Do not use it for other purposes, since
misuse may result in personal injury or
property damage, including damage to
the machine.
WARNING
Minors should never be allowed to use
this power tool. Bystanders, especially
children, and animals should not be
allowed in the area where it is in use.
WARNING
To reduce the risk of injury to bystanders
and damage to property, never let your
power tool run unattended. When it is
not in use (e.g. during a work break),
shut it off and make sure that
unauthorized persons do not use it.
Most of these safety precautions and
warnings apply to the use of all STIHL
bed redefiners. Different models may
have different parts and controls. See
the appropriate section of this instruction
manual for a description of the controls
and function of the parts of your model.
Safe use of a bed redefiner involves
1. the operator
2. the power tool
3. the use of the power tool.
THE OPERATOR
Physical Condition
You must be in good physical condition
and mental health and not under the
influence of any substance (drugs,
alcohol, etc.) which might impair vision,
dexterity or judgment. Do not operate
this machine when you are fatigued.
WARNING
Be alert – if you get tired, take a break.
Tiredness may result in loss of control.
Working with any power tool can be
strenuous. If you have any condition that
might be aggravated by strenuous work,
check with your doctor before operating
this machine.
WARNING
Prolonged use of a power tool (or other
machines) exposing the operator to
vibrations may produce whitefinger
disease (Raynaud's phenomenon) or
carpal tunnel syndrome.
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These conditions reduce the hand's
ability to feel and regulate temperature,
produce numbness and burning
sensations and may cause nerve and
circulation damage and tissue necrosis.
All factors which contribute to
whitefinger disease are not known, but
cold weather, smoking and diseases or
physical conditions that affect blood
vessels and blood transport, as well as
high vibration levels and long periods of
exposure to vibration are mentioned as
factors in the development of whitefinger
disease. In order to reduce the risk of
whitefinger disease and carpal tunnel
syndrome, please note the following:
– Most STIHL power tools are
available with an anti-vibration
("AV") system designed to reduce
the transmission of vibrations
created by the machine to the
operator's hands. An AV system is
recommended for those persons
using power tools on a regular or
sustained basis.
– Wear gloves and keep your hands
warm.
– Keep the AV system well
maintained. A power tool with loose
components or with damaged or
worn AV elements will tend to have
higher vibration levels.
– Maintain a firm grip at all times, but
do not squeeze the handles with
constant, excessive pressure. Take
frequent breaks.
All the above-mentioned precautions do
not guarantee that you will not sustain
whitefinger disease or carpal tunnel
syndrome. Therefore, continual and
regular users should closely monitor the
condition of their hands and fingers. If
any of the above symptoms appear,
seek medical advice immediately.
WARNING
The ignition system of the STIHL unit
produces an electromagnetic field of a
very low intensity. This field may
interfere with some pacemakers. To
reduce the risk of serious or fatal injury,
persons with a pacemaker should
consult their physician and the
pacemaker manufacturer before
operating this tool.
Proper Clothing
WARNING
To reduce the risk of injury, the operator
should wear proper protective apparel.
The deflector provided with your power
tool will not protect the operator from all
foreign objects (gravel, glass, wire, etc.)
thrown back by the rotating cutting
attachment. Thrown objects may also
ricochet and strike the operator.
WARNING
To reduce the risk of
injury to your eyes never
operate your power tool
unless wearing goggles
or properly fitted protective glasses with
adequate top and side
protection complying with
ANSI Z87 "+" (or your
applicable national standard). If there is a risk of
injury to the operator´s
face, STIHL recommends
that you also wear a face
shield or face screen over
your goggles or protective glasses.
WARNING
Power tool noise may
damage your hearing.
Wear sound barriers (ear
plugs or ear mufflers) to
protect your hearing.
Continual and regular
users should have their
hearing checked
regularly.
Be particularly alert and cautious when
wearing hearing protection because
your ability to hear warnings (shouts,
alarms, etc.) is restricted.
4
FB 131
English
Always wear heavy duty
work gloves (e.g. made of
leather or other wear
resistant material) when
handling the machine
and metal blades. Heavyduty, nonslip gloves
improve your grip and
help to protect your
hands.
Clothing must be sturdy
and snug-fitting, but allow
complete freedom of
movement. Wear long
pants made of heavy
material to help protect
your legs. Do not wear
shorts, sandals or go
barefoot.
Avoid loose-fitting jackets, scarfs,
neckties, jewelry, flared or cuffed pants,
unconfined long hair or anything that
could become caught on branches,
brush or the moving parts of the unit.
Secure hair so it is above shoulder level.
Good footing is very
important. Wear sturdy
boots with nonslip soles.
Steel-toed safety boots
are recommended.
Wear an approved safety
hard hat to reduce the
risk of injury to your head
when there is a danger of
head injuries.
THE POWER TOOL
For illustrations and definitions of the
power tool parts see the chapter on
"Main Parts."
WARNING
Never modify this power tool in any way.
Only attachments supplied by STIHL
and expressly approved by STIHL for
use with the specific STIHL model are
authorized. Although certain
unauthorized attachments are useable
with STIHL power tools, their use may,
in fact, be extremely dangerous.
If this tool is subjected to unusually high
loads for which it was not designed (e.g.
heavy impact or a fall), always check
that it is in good condition before
continuing work. Check in particular that
the fuel system is tight (no leaks) and
that the controls and safety devices are
working properly. Do not continue
operating this machine if it is damaged.
In case of doubt, have it checked by your
STIHL servicing dealer.
THE USE OF THE POWER TOOL
Transporting the Power Tool
WARNING
To reduce the risk of injury from loss of
control and blade contact, never carry or
transport your power tool with the cutting
attachment moving.
0000-GXX-1560-A0
It may be carried only in a horizontal
position. Grip the shaft in a manner that
the machine is balanced horizontally.
Keep the hot muffler away from your
body and the cutting attachment behind
you.
WARNING
Always shut off the engine and make
sure that the cutting blade has stopped
before putting the power tool down.
When transporting it in a vehicle,
properly secure it to prevent turnover,
fuel spillage and damage to the unit.
Fuel
Your STIHL power tool uses an oil-
gasoline mixture for fuel (see the
chapter on "Fuel" in this instruction
manual.)
FB 131
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English
WARNING
Gasoline is an extremely
flammable fuel. If spilled
and ignited by a spark or
other ignition source, it
can cause fire and serious burn injury or
property damage. Use
extreme caution when
handling gasoline or fuel
mix. Do not smoke or
bring any fire or flame
near the fuel or the power
tool. Note that combustible fuel vapor may
escape from the fuel system or gas can during
fueling operations.
Fueling Instructions
WARNING
To reduce the risk of serious burn injury
from fire, never attempt to refuel the unit
until it has been completely removed
from the operator.
WARNING
Fuel your machinel in well-ventilated
areas, outdoors. Always shut off the
engine and allow it to cool before
refueling. Gasoline vapor pressure may
build up inside the fuel tank depending
on the fuel used, the weather or
environmental conditions and the use of
the machine.
In order to reduce the risk of burns and
other personal injury from escaping gas
vapor and fumes, remove the fuel filler
cap on your power tool carefully so as to
allow any pressure build-up in the tank
to release slowly. Never remove the fuel
filler cap while the engine is running.
Select bare ground for fueling and move
at least 10 feet (3 m) from the fueling
spot before starting the engine. Wipe off
any spilled fuel before starting your
machine.
WARNING
Check for fuel leakage
while refueling and during
operation. If fuel leakage
is found, do not start or
run the machine until the
leak is fixed and any
leaked fuel has been
wiped away. Take care
not to get fuel on your
clothing. If this happens,
change your clothing
immediately.
WARNING
To reduce the risk of fuel spillage and
fire from an improperly installed fuel cap,
correctly position and tighten the fuel
cap in the fuel tank opening.
WARNING
Unit vibrations can cause
an improperly installed
fuel filler cap to loosen or
come off and spill quantities of fuel. In order to
reduce the risk of fuel
spillage and fire, tighten
the fuel filler cap by hand
as securely as possible.
See also the "Fueling" chapter in your
Instruction Manual for additional
information.
Before Starting
WARNING
Always check your power tool for proper
condition and operation before starting,
particularly the throttle trigger, throttle
trigger lockout, stop switch, cutting
blade, deflector and harness. The
throttle trigger must move freely and
always spring back to the idle position.
Never attempt to modify the controls or
safety devices. Never use a power tool
that is damaged or not properly
maintained.
WARNING
Check fuel system for leaks, especially
the visible parts, e.g., filler cap, hose
connections, manual fuel pump (only for
power tools equipped with a manual fuel
pump). To reduce the risk of personal
injury or property damage from fire, do
not start the engine if there are leaks or
damage. Have the machine repaired by
a servicing dealer before using it.
WARNING
Do not attach any cutting attachment to
a unit without proper installation of all
required parts. Failure to use the proper
parts may cause the blade to fly off and
seriously injure the operator or
bystanders.
6
FB 131
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9924BA001 KN
WARNING
The cutting attachment and deflector
must be properly tightened and in safe
operating condition. Inspect for loose
parts (nuts, screws, etc.) and for
cracked, bent, warped or damaged
blades. Replace a damaged blade or
deflector before using the power tool.
Keep the handles clean and dry at all
times; it is particularly important to keep
them free of moisture, pitch, oil, fuel mix,
grease or resin in order for you to
maintain a firm grip and properly control
your power tool.
WARNING
Check that the spark plug boot is
securely mounted on the spark plug – a
loose boot may cause arcing that could
ignite combustible fumes and cause a
fire.
WARNING
To reduce the risk
of personal injury
to the operator
from blade contact and thrown
objects, make sure
your unit is
equipped with the
proper deflector,
skirt and handle.
An arrow on the deflector shows the
correct direction of rotation of the cutting
blade.
The arrow on the deflector must always
face away from you, so that cuttings and
other debris will be diverted away from
the machine and your position (see
chapter "Working Techniques".)
For proper control and less fatigue
during operation, adjust the loop handle
to suit your size before starting work.
Starting
WARNING
To reduce the risk of serious personal
injury from fire, start the engine at least
10 feet (3 m) from the fueling spot,
outdoors only.
For specific starting instructions, see the
appropriate section of your manual.
Place the power tool on firm ground or
other solid surface in an open area.
Maintain good balance and secure
footing.
WARNING
To reduce the risk of injury from blade
contact, be absolutely sure that the
cutting attachment is clear of you and all
other obstructions and objects, including
the ground, because when the engine
starts at starting-throttle, engine speed
will be fast enough for the clutch to
engage and move the cutting
attachment.
Once the engine has started,
immediately blip the throttle trigger,
which should release the starting throttle
and allow the engine to slow down to
idle.
WARNING
Your power tool is a one-person
machine. Do not allow other persons in
the general work area, even when
starting.
WARNING
To reduce the risk of injury from loss of
control, do not attempt to "drop start"
your power tool. Drop starting means
pushing the machine away from the
operator, or allowing it to drop toward
the ground, while pulling on the starter
grip. This method is very dangerous
bescause you may lose control of the
machine.
WARNING
When you pull the starter grip, do not
wrap the starter rope around your hand.
Do not let the grip snap back, but guide
the starter rope to permit the rope to
rewind properly. Failure to follow this
procedure may result in injury to your
hand or fingers and may damage the
starter mechanism.
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Important Adjustments
WARNING
To reduce the risk of personal injury
from loss of control or contact with the
running cutting attachment, do not use
your unit with incorrect idle adjustment.
At correct idle speed, the cutting
attachment should not move. For
directions on how to adjust idle speed,
see the appropriate section of this
instruction manual.
If you cannot set the correct idle speed,
have your STIHL dealer check your
power tool and make proper
adjustments and repairs.
During Operation
Holding and Controlling the Power Tool
Always hold the unit firmly with both
hands on the handles while you are
working. Wrap your fingers and thumbs
around the handles.
Place your left hand on the loop handle
and your right hand on the rear handle.
Left-handers must follow these
instructions too.
WARNING
To reduce the risk of injury from loss of
control, always pull your power tool, do
not push it forward. Plan the direction of
cut and always keep the cutting
attachment in the rear. Maintain
sufficient distance from the cutting
attachment at all times to avoid contact
with the operator. See the chapter on
"Using the Unit" in this instruction
manual.
WARNING
Never attempt to operate
your power tool with one
hand. Loss of control of
the power tool resulting in
serious or fatal injury may
result. To reduce the risk
of cut injuries, keep
hands and feet away
from the cutting attachment. Never touch a
moving cutting attachment with your hand or
any other part of your
body.
0000-GXX-1559-A0
WARNING
Do not overreach. Keep proper footing
and balance at all times. Special care
must be taken in slippery conditions (wet
ground, snow) and in difficult, overgrown
terrain. Watch for hidden obstacles such
as tree stumps, roots and ditches to
avoid stumbling. For better footing, clear
away scrub and cuttings. Be extremely
cautious when working on slopes or
uneven ground.
Working Conditions
Operate and start your power tool only
outdoors in a well ventilated area.
Operate it under good visibility and
daylight conditions only. Work carefully.
WARNING
As soon as the engine is
running, this machine
generates toxic exhaust
fumes containing chemicals, such as unburned
hydrocarbons (including
benzene) and carbon
monoxide, that are
known to cause respiratory problems, cancer,
birth defects, or other
reproductive harm and
other injuries. Some of
the gases (e.g. carbon
monoxide) may be colorless and odorless and
can cause asphyxiation
or death very quickly. To
reduce the risk of serious
or fatal injury / illness
from inhaling toxic fumes,
never run the machine
indoors or in poorly ventilated locations.
WARNING
If the vegetation being cut or the
surrounding ground is coated with a
chemical substance (such as an active
pesticide or herbicide), read and follow
the instructions and warnings that
accompanied the substance at issue.
8
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15 m (50 ft)
WARNING
Inhalation of certain dusts, especially
organic dusts such as mold or pollen,
can cause susceptible persons to have
an allergic or asthmatic reaction.
Substantial or repeated inhalation of
dust and other airborne contaminants, in
particular those with a smaller particle
size, may cause respiratory or other
illnesses. Control dust at the source
where possible. Use good work
practices, such as operating the unit so
that the wind or operating process
directs any dust raised by the power tool
away from the operator. Follow the
recommendations of EPA / OSHA /
NIOSH and occupational and trade
associations with respect to dust
("particulate matter"). When the
inhalation of dust cannot be
substantially controlled, i.e., kept at or
near the ambient (background) level, the
operator and any bystanders should
wear a respirator approved by NIOSH /
MSHA for the type of dust encountered.
Operating Instructions
WARNING
Do not operate your power tool using the
starting throttle lock, as you do not have
control of the engine speed.
In the event of an emergency, switch off
the engine immediately by pressing the
stop switch.
WARNING
The cutting attachment continues to
rotate for a short period after the throttle
trigger is released (flywheel effect.)
WARNING
The rotating cutting attachment may
fling foreign objects directly or by
ricochet a great distance.
To reduce the risk of eye and other
injury, always wear proper eye
protection (see the chapter on "Proper
Clothing") and ensure that bystanders
are at least 50 feet (15 m) away. To
reduce the risk of damage to property,
also maintain this distance from such
objects as vehicles or windows. Even
maintaining a minimum distance of
15 meters cannot exclude the potential
danger. Any coworkers who must be in
the restricted area should also wear
goggles or protective glasses. Stop the
engine immediately if you are
approached.
WARNING
Inspect the work area: To
reduce the risk of injury,
remove stones, pieces of
metal and other solid
objects which could be
thrown 15 meters or more
by the cutting attachment
or damage the cutting
attachment and property
(e.g. parked vehicles,
windows).
WARNING
This bed redefiner is normally to be used
at ground level with the blade
perpendicular to the ground. Use of a
bed redefiner above ground level or with
the cutting attachment parallel to the
ground may increase the risk of injury,
since the cutting attachment is more fully
exposed and the bed redefiner may be
more difficult to control.
WARNING
During cutting, check the tightness and
the condition of the cutting attachment at
regular short intervals with the engine
and attachment stopped. If the behavior
of the attachment changes during use,
stop the engine immediately, wait until
the cutting attachment stops, and check
the nut securing the attachment for
tightness and the blade for cracks, wear
and damage.
WARNING
A loose blade may vibrate, crack, break
or come off the bed redefiner, which may
result in serious or fatal injury. Make
sure that the cutting attachment is
properly tightened. Use the wrench
supplied or one of sufficient length to
obtain the proper torque. If the blade
loosens after being properly tightened,
stop work immediately. The retaining nut
may be worn or damaged and should be
replaced. If the blade continues to
loosen, see your STIHL dealer. Never
use a bed redefiner with a loose cutting
attachment.
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WARNING
Replace a cracked, bent, warped,
damaged, dull or worn out blade
immediately, even if damage is limited to
superficial cracks. Such attachments
may shatter at high speed and cause
serious or fatal injury.
WARNING
When using your bed redefiner, avoid
cutting close to fences, sides of
buildings, tree trunks, stones or other
such objects that cause the power tool to
kick out or could cause damage to the
blade.
WARNING
If a rotating metal blade strikes a rock or
other hard object, sparks may be
created, which can ignite flammable
materials under certain circumstances.
Flammable materials can include dry
vegetation and brush, particularly when
weather conditions are hot and dry.
When there is a risk of fire or wildfire, do
not use metal blades around flammable
materials or around dry vegetation or
brush. Contact your local fire authorities
or the U.S. Forest Service if you have
any question about whether vegetation
and weather conditions are suitable for
the use of a metal blade.
WARNING
If the blade or deflector becomes
clogged or stuck, always shut off the
engine and make sure the cutting
attachment has stopped before
cleaning. Grass, weeds, etc. should be
cleaned off the blade at regular intervals.
WARNING
To reduce the risk of unintentional
rotation of the cutting attachment and
injury, always shut off the engine before
replacing the cutting attachment.
WARNING
The gearbox becomes hot during
operation. To reduce the risk of burn
injury, do not touch the gear housing
when it is hot.
WARNING
Never modify your muffler. Any
modification could cause an increase in
heat radiation, sparks or sound level,
thereby increasing the risk of fire, burn
injury or hearing loss. You may also
permanently damage the engine. STIHL
recommends having your muffler
serviced and repaired by your STIHL
servicing dealer.
WARNING
The muffler and other parts of the engine
(e.g. fins of the cylinder, spark plug)
become hot during operation and remain
hot for a while after stopping the engine.
To reduce risk of burns, do not touch the
muffler and other parts while they are
hot. Keep the area around the muffler
clean. Remove excess lubricant and all
debris such as pine needles, branches
or leaves. Let the engine cool down
sitting on concrete, metal, bare ground
or solid wood away from any
combustible substances.
WARNING
An improperly mounted or damaged
cylinder housing or a
damaged/deformed muffler shell may
interfere with the cooling process of the
muffler. To reduce the risk of fire or burn
injury, do not continue work with a
damaged or improperly mounted
cylinder housing or a
damaged/deformed muffler shell.
Your muffler is furnished with a spark
arresting screen designed to reduce the
risk of fire from the emission of hot
particles. Never operate your unit with a
missing or damaged spark arresting
screen. If your gas/oil mix ratio is correct
(i.e., not too rich), this screen will
normally stay clean as a result of the
heat from the muffler and need no
service or maintenance. If you
experience loss of performance and you
suspect a clogged screen, have your
muffler maintained by a STIHL servicing
dealer. Some state or federal laws or
regulations may require a properly
maintained spark arrestor for certain
uses. See the "Maintenance, Repair and
Storing" section of these Safety
Precautions. Remember that the risk of
a brush or forest fire is greater in hot or
dry conditions.
USING THE CUTTING ATTACHMENT
For an illustration of the cutting
attachment and instructions on proper
mounting see the chapter on "Replacing
the Cutting Blade" in this instruction
manual.
10
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WARNING
To reduce the risk of severe or fatal
injury from blade contact and/or loss of
control, never attempt to use a metal
blade on a FB model for which it is not
authorized.
MAINTENANCE, REPAIR AND
STORING
Maintenance, replacement, or repair of
the emission control devices and
systems may be performed by any
nonroad engine repair establishment or
individual. However, if you make a
warranty claim for a component which
has not been serviced or maintained
properly, STIHL may deny coverage.
WARNING
STIHL recommends the use of only
STIHL replacement parts for
maintenance and repair. Use of parts
manufactured by others may be
extremely dangerous and could result in
serious or fatal injury.
Strictly follow the maintenance and
repair instructions in the appropriate
sections of this instruction manual.
WARNING
Always stop the engine and make sure
that the cutting attachment is stopped
before doing any maintenance or repair
work or cleaning the power tool. Do not
attempt any maintenance or repair work
not described in this instruction manual.
STIHL recommends that you have such
work performed by your STIHL servicing
dealer.
Wear gloves when handling or
performing maintenance on blades.
WARNING
To reduce the risk of fire and burn injury
or property damage, use only spark
plugs authorized by STIHL. Always
press the spark plug boot snugly onto
the spark plug terminal of the proper
size. (Note: If the terminal has a
detachable SAE adapter nut, it must be
securely attached.) A loose connection
between the spark plug and the ignition
wire connector in the boot may create
arcing that could ignite combustible
fumes and cause a fire. Keep the spark
plug clean and make sure the ignition
lead is in good condition.
WARNING
Never test the ignition system with the
spark plug boot removed from the spark
plug or with a removed spark plug, since
uncontained sparking may cause a fire.
WARNING
Do not operate your power tool if the
muffler is damaged, missing or modified.
An improperly maintained muffler will
increase the risk of fire and hearing loss.
Your muffler is equipped with a sparkarresting screen to reduce the risk of
fire; never operate your power tool if the
screen is missing, damaged or clogged.
Remember that the risk of a brush or
forest fire is greater in hot or dry
weather.
In California, it is a violation of § 4442 or
§ 4443 of the Public Resources Code to
use or operate gasoline-powered tools
on forest-covered, brush-covered or
grass-covered land unless the engine’s
exhaust system is equipped with a
complying spark arrester that is
maintained in effective working order.
The owner/operator of this product is
responsible for properly maintaining the
spark arrester. Other states or
governmental entities/agencies, such as
the U.S. Forest Service, may have
similar requirements. Contact your local
fire agency or forest service for the laws
or regulations relating to fire protection
requirements.
WARNING
Never repair damaged cutting
attachments by welding, straightening or
modifying the shape. This may cause
parts of the cutting attachment to come
off and result in serious or fatal injuries.
Tighten all nuts, bolts and screws,
except the carburetor adjustment
screws, after each use.
Do not clean your machine with a
pressure washer. The solid jet of water
may damage parts of the machine.
Store the power tool in a dry and high or
locked location out of reach of children.
Before storing for longer than a few
days, always empty the fuel tank. See
chapter "Storing the Machine" in this
instruction manual.
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0000-GXX-1624-A0
1
A
9924BA004 KN
2
3
9924BA005 KN
A
9924BA006 KN
Using the Unit
Your bed redefiner is suitable for
recutting existing flowerbed edges to
restore their sharp contours. Redefining
produces a sharp angled furrow.
attachment to the rear. Maintain a
safe distance from the cutting
attachment at all times.
Adjusting Depth of Cut
N To reduce the risk of accidents,
shut off the engine and wait until the
cutting attachment comes to a
standstill.
N Loosen the wingnut (1)
counterclockwise.
N Push wheel (2) upwards to increase
the depth of cut (A) or downwards to
reduce the depth of cut (A).
The depth of cut (A) depends on the
uneveness of the ground, your height
and normal working position. Therefore:
N move the wheel (2) so that the
blade (3) touches the ground in the
normal working position.
N Always pull the power tool, do not
push it forward – work in the
direction shown by the arrow.
Preparations
WARNING
To reduce the risk of accidents or injury,
remove all obstacles and objects from
the work area.
N Plan the best route for redefining.
Always hold and operate your
power tool on the left-hand side of
your body with the cutting
12
N Tighten down the wingnut
clockwise.
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9924BA031 KN
1
9924BA023 KN
9924BA027 KN
1
Redefining bed edges
The arrow (1) on the deflector indicates
the direction of operation.
The deflector is set at the factory with its
open side facing away from the
operator. This ensures that cuttings and
other debris are directed away from the
power tool and operator.
N Hold and guide your power tool so
that the blade is vertical.
N Cut steadily so that the engine is not
lugged down – do not apply force.
N Operate at no more than a normal
walking pace.
N Do not push the blade into the
ground.
N Always pull the power tool, do not
push it forward.
WARNING
Always hold and operate your power tool
on the left-hand side of your body with
the cutting attachment to the rear.
Maintain a safe distance from the cutting
attachment at all times.
N Cut at a steady pace to avoid having
to make several passes.
Approved Power Tool
Attachments
The following STIHL attachments may
be mounted to the basic power tool:
Interchangeable
Attachment Application
BF Cultivator with pick
tines
HL 145° Long reach hedge
trimmer
HT Pole pruner
KB (4601) Bristle brush
KW (4601) PowerSweep
N Starting the Engine
N Start the cut at no less than half
throttle and continue cutting at full
throttle.
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N Use the gunning sight (1) to line the
blade up with the edge of the bed.
13
English
9924BA007 KN
1
1
239BA008 KN
0000-GXX-1563-A0
A
0000-GXX-1562-A0
Approved Cutting
Attachments
1 Blade (marked 4180/00)
Mounting the Loop Handle
Your new power tool comes with the
loop handle mounted on the drive tube,
but it must be turned and lined up to suit
your requirements.
Adjusting the Loop Handle
N Use the combination wrench to
loosen the screw (1).
The loop handle can be adjusted to suit
the height and reach of the operator and
the application by changing
distance (A).
Recommendation: distance (A):
about 6 in (15 cm)
N Slide the handle to the required
position.
N Tighten down the screw with the
combination wrench so that the
handle cannot be rotated on the
drive tube.
14
N Turn the handle to the vertical
position.
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002BA655 KN
Adjusting the Throttle Cable
It may be necessary to correct the
adjustment of the throttle cable after
assembling the machine or after a
prolonged period of operation.
Adjust the throttle cable only when the
unit is completely and properly
assembled.
N Set the throttle trigger to the full
throttle position.
N Carefully rotate the screw in the
throttle trigger in the direction of the
arrow until you feel initial resistance.
Then rotate it another half turn in the
same direction.
Fuel
This engine is certified to operate on
unleaded gasoline and the STIHL twostroke engine oil at a mix ratio of 50:1.
Your engine requires a mixture of highquality gasoline and two-stroke air
cooled engine oil.
Use mid-grade unleaded gasoline with a
minimum octane rating of 89 ((R+M)/2)
and no more than 10% ethanol content.
Fuel with an octane rating below 89 may
increase engine temperatures. This, in
turn, increases the risk of piston seizure
and damage to the engine.
The chemical composition of the fuel is
also important. Some fuel additives not
only detrimentally affect elastomers
(carburetor diaphragms, oil seals, fuel
lines, etc.), but magnesium castings and
catalytic converters as well. This could
cause running problems or damage the
engine. For this reason STIHL
recommends that you use only quality
unleaded gasoline!
Gasoline with an ethanol content of
more than 10% can cause running
problems and major damage in engines
and should not be used.
For further details, see
www.STIHLusa.com/ethanol
The ethanol content in gasoline affects
engine speed – it may be necessary to
readjust the carburetor if you use fuels
with various ethanol contents.
WARNING
To reduce the risk of personal injury
from loss of control and / or contact with
the running cutting tool, do not use your
unit with incorrect idle adjustment. At
correct idle speed, the cutting tool
should not move.
If your power tool´s idle speed is
incorrectly adjusted, have your
authorized STIHL servicing dealer
check your machine and make the
proper adjustments and repairs.
The idle speed and maximum speed of
the engine change if you switch from a
fuel with a certain ethanol content to
another fuel with a much higher or lower
ethanol content.
This problem can be avoided by always
using fuel with the same ethanol
content.
To ensure the maximum performance of
your STIHL engine, use a high quality 2cycle engine oil, such as STIHL 2-cycle
engine oils. STIHL 2-cycle engine oils
are specially designed for STIHL
engines. To help your engine run
cleaner and reduce harmful carbon
deposits, STIHL recommends using
STIHL HP Ultra 2-cycle engine oil, or
use an equivalent high quality 2-cycle
engine oil.
To meet the requirements of EPA and
CARB we recommend to use STIHL HP
Ultra oil or equivalent.
Do not use BIA or TCW rated (twostroke water cooled) mix oils or other
mix oils that state they are for use in both
water cooled and air cooled engines
(e.g., outboard motors, snowmobiles,
chain saws, mopeds, etc.).
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0000-GXX-0476-A0
Take care when handling gasoline.
Avoid direct contact with the skin and
avoid inhaling fuel vapor. When filling at
the pump, first remove the container
from your vehicle and place the
container on the ground before filling. To
reduce the risk of sparks from static
discharge and resulting fire and/or
explosion, do not fill fuel containers that
are sitting in or on a vehicle or trailer.
The container should be kept tightly
closed in order to limit the amount of
moisture that gets into the mixture.
The machine’s fuel tank should be
cleaned as necessary.
STIHL MotoMix
STIHL recommends the use of STIHL
MotoMix. STIHL MotoMix has a high
octane rating and ensures that you
always use the right gasoline/oil mix
ratio.
STIHL MotoMix uses STIHL HP Ultra
two-stroke engine oil suited for high
performance engines.
For further details, see
www.STIHLusa.com/ethanol
Fuel mix ages
If not using STIHL MotoMix, only mix
sufficient fuel for a few days of work, not
to exceed 30 days of storage. Store in
approved fuel-containers only. When
mixing, pour oil into the container first,
and then add gasoline. Close the
container and shake it vigorously by
hand to ensure proper mix of oil and
gasoline.
Gasoline Oil (STIHL 50:1 or equiva-
lent high-quality oils)
Liters Liters (ml)
10.02(20)
5 0.10 (100)
10 0.20 (200)
20 0.40 (400)
US gal. US fl.oz.
12.6
2 1/2 6.4
512.8
Dispose of empty mixing-oil containers
only at authorized disposal locations.
Fueling
Preparations
N Before fueling, clean the filler cap
and the area around it to ensure that
no dirt falls into the tank.
Always thoroughly shake the mixture in
the canister before fueling your
machine.
N Position the machine so that the
filler cap is facing up.
WARNING
To reduce the risk of fire and personal
injuries due to escaping fuel and vapor,
remove the fuel filler cap carefully so
that any excess pressure in the tank can
escape slowly.
Use the proper seasonal gasoline blend,
i.e., winter blend in winter, summer
blend in summer.
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002BA447 KN
002BA448 KN
2
1
3
0000-GXX-0477-A0
Opening the threaded filler cap
N Turn the cap counterclockwise until
it can be removed from the tank
opening.
N Remove the filler cap.
Refueling
Take care not to spill fuel while fueling
and do not overfill the tank.
Closing the threaded filler cap
N Position cap.
N Turn the cap clockwise as far as it
will go and tighten it as securely as
possible by hand.
Starting / Stopping the
Engine
Controls
1 Throttle trigger lockout
2 Throttle trigger
3 Stop switch with Run and Stop
positions. Depress the stop switch
(…) to switch off the ignition – see
"Function of stop switch and ignition
system".
Function of stop switch and ignition
system
The ignition is switched off and the
engine stopped when the stop switch is
pressed. The stop switch returns
automatically to the Run position when it
is released: The ignition is switched on
again after the engine stops – the engine
is then ready to start.
Starting the Engine
0000-GXX-0478-A0
N Press the manual fuel pump
bulb (9) at least five times – even if
the bulb is already filled with fuel.
N Press in the choke knob (8) and turn
it to the position that suits the engine
temperature:
g if the engine is cold
< for warm start – also use this posi-
tion if the engine has been running
but is still cold.
The choke knob must engage in
position.
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0000-GXX-1674-A0
0000-GXX-1319-A0
0000-GXX-1320-A0
0000-GXX-1558-A0
Cranking
N Place the unit on the ground: It must
rest securely on the engine support
and the deflector.
To reduce the risk of accidents, check
that the cutting attachment is not
touching the ground or any other
obstacles.
N Make sure you have a firm footing,
either standing, stooping or
kneeling.
N Hold the unit firmly on the ground
with your left hand and press down
– do not touch the throttle trigger or
lockout lever – your thumb should
be under the fan housing.
NOTICE
Do not stand or kneel on the drive tube.
N Hold the starter grip with your right
hand.
N 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.
N Do not let the starter grip snap back.
Guide it slowly back into the housing
so that the starter rope can rewind
properly.
N Continue cranking until the engine
runs.
As soon as the engine runs
N Press down the throttle trigger
lockout and open the throttle – the
choke knob moves to the run
position F. After a cold start, warm
up the engine by opening the
throttle several times.
WARNING
There is a risk of injury if the cutting
attachment runs when the engine is
idling. Adjust the carburetor so that the
cutting attachment does not run when
the engine is idling – see “Adjusting the
Carburetor”.
Your machine is now ready for
operation.
Stopping the Engine
N Depress the momentary contact
stop switch – the engine stops –
release the stop switch – it springs
back to the run position.
Other Hints on Starting
Engine stalls in cold start position g or
under acceleration.
N Move the choke knob to < and
continue cranking until the engine
runs.
Engine does not start in warm start
position <
N Move the choke knob to g and
continue cranking until the engine
runs.
If the engine does not start
N Check that all settings are correct.
N Check that there is fuel in the tank
and refuel if necessary.
N Check that the spark plug boot is
properly connected.
N Repeat the starting procedure.
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1
1
0000-GXX-0482-A0
2
3
4
Engine is flooded
N Move the choke knob to F and
continue cranking until the engine
runs.
Fuel tank run until completely dry
N After refueling, press the manual
fuel pump bulb at least five times –
even if the bulb is already filled with
fuel.
N Set the choke lever to suit the
engine temperature.
N Now start the engine.
Operating Instructions Replacing the Air Filter
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 during 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.
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 enginemounted components (ignition,
carburetor) from thermal overload.
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 out-ofservice periods – see "Storing the
Machine".
Filters have an average life of more than
a year. Do not remove the filter cover or
replace the air filter as long as there is no
noticeable loss of power.
If there is a noticeable loss of engine
power
N Turn the choke knob to g.
N Loosen the screws (1).
N Remove the filter cover (2).
N Clean away loose dirt from around
the filter.
N Remove the filter element (3).
N Replace dirty or damaged filter
element (3).
N Replace any damaged parts.
Installing the Filter Element
N Install the filter element (3) in the
filter housing and fit the cover.
N Insert the screws (1) and tighten
them down firmly.
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0000-GXX-0495-A0
0000-GXX-0486-A0
4
5
Engine Management Adjusting the Carburetor
Exhaust emissions are controlled by the
design of the engine and components
(e.g. carburation, ignition, timing and
valve or port timing).
The carburetor has been set at the
factory to provide an optimum fuel-air
mixture under most operating
conditions.
Adjusting Idle Speed
Engine stops while idling
N Warm up the engine for about
3 minutes.
N Turn the idle speed screw (LA)
slowly clockwise until the engine
runs smoothly – the cutting
attachment must not run.
Cutting attachment runs when engine is
idling
N Turn the idle speed screw (LA)
slowly counterclockwise until the
cutting attachment stops running
and then turn the screw about
another 1/2 to 3/4 turn in the same
direction.
Spark Arresting Screen in
Muffler
N If the engine is down on power,
check the spark arresting screen in
the muffler.
N Wait for the muffler to cool down.
N Take out the screw (4).
N Lift the spark arresting screen (5)
and pull it out.
N Clean the spark arresting
screen (5). If the screen is damaged
or heavily carbonized, install a new
one.
N Refit the spark arresting screen (5).
N Insert the screw (4) and tighten it
down firmly.
20
WARNING
If the cutting attachment continues to run
when the engine is idling, have your
machine checked and repaired by your
servicing dealer.
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000BA039 KN
A
2
1
0000-GXX-1831-A0
3
Spark Plug
If the engine is down on power, difficult
to start or runs poorly at idling speed,
first check the spark plug.
Install a new spark plug after approx.
100 operating hours or earlier if the
electrodes are badly eroded/corroded.
The wrong fuel mix (too much engine oil
in the gasoline), a dirty air filter and
unfavorable running conditions (mostly
at part throttle etc.) affect the condition
of the spark plug. These factors cause
deposits to form on the insulator nose
which may degrade performance.
Removing the Spark Plug
1
2
3
N Remove the cover (1).
N Pull off the spark plug boot (2).
N Unscrew the spark plug (3).
Checking the Spark Plug
N Clean dirty spark plug.
N Check electrode gap (A) and
readjust if necessary – see chapter
"Specifications."
N Use only resistor type spark plugs of
the approved range.
Rectify problems which have caused
fouling of spark plug:
– too much oil in fuel mix,
– dirty air filter,
– unfavorable running conditions, e.g.
operating at part load.
0000-GXX 0537-A0
WARNING
To redu ce the risk of fire and burn injury,
use only spark plugs authorized by
STIHL. Always press the spark plug
boot (1) snugly onto the spark plug
terminal (2).
Do not use a spark plug with a
detachable SAE adapter terminal (3).
Arcing may occur that could ignite
combustible fumes and cause a fire.
This can result in serious injuries or
damage to property.
N Only use resistor type spark plugs
with solid, non-threaded terminals
Installing the Spark Plug
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N Screw the spark plug (3) into the
cylinder.
N Tighten down the spark plug (3) with
the combination wrench.
21
English
1
9924BA015 KN
2
N Press the boot (2) firmly onto the
spark plug.
N Fit the cover (1) and screw it down
firmly.
Storing the Machine Replacing the Depth Wheel
For periods of 3 months or longer
N Drain and clean the fuel tank in a
well ventilated area.
N Dispose of fuel properly in
accordance with local
environmental requirements.
N Run the engine until the carburetor
is dry – this helps prevent the
carburetor diaphragms sticking
together.
N Thoroughly clean the machine – pay
special attention to the cylinder fins
and air filter.
N Remove, clean and inspect the
cutting blade.
N Store the machine in a dry, high or
locked location, out of the reach of
children and other unauthorized
persons.
Have a worn depth wheel replaced by a
servicing dealer. STIHL recommends
that you have servicing and repair work
carried out exclusively by an authorized
STIHL servicing dealer.
N The end of the thread on the
screw (1) is peened over to ensure
that the wingnut (2) does not work
loose and be lost.
A very high torque has to be applied to
remove the wingnut from the screw. If
the parts are then reassembled, the
captive function is no longer
guaranteed. In such a case have the
screw and wingnut replaced by a
servicing dealer.
22
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