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Stihl FC 90 User manual

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{
STIHL FC 90
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 - 38
Manual de instrucciones
39 - 81
Original Instruction ManualPrinted on chlorine-free paper
Printing inks contain vegetable oils, paper can be recycled.
© ANDREAS STIHL AG & Co. KG, 2015
0458-237-8621-F. VA1.A15.
0000006738_002_GB
FC 90
English
1
{This instruction manual is protected by copyright. All rights reserved, especially the rights to reproduce, translate and process
with electronic systems.
Contents
Allow only persons who fully understand
this manual to operate your edger.
To receive maximum performance and
satisfaction from your STIHL edger, 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
edger. 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 an edger 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.
Make sure your unit is equipped with the
proper deflector and handle for the type
of cutting attachment being used.
Always wear proper eye protection.
Guide to Using this Manual 2
Safety Precautions and Working
Techniques 3
Using the Unit 12
Mounting the Loop Handle 14
Adjusting the Throttle Cable 16
Mounting the Cutting Blade 16
4-MIX Engine 17
Fuel 17
Fueling 18
Starting / Stopping the Engine 20
Operating Instructions 22
Cleaning the Air Filter 22
Engine Management 22
Adjusting the Carburetor 23
Spark Arresting Screen in Muffler 23
Spark Plug 24
Rewind Starter 25
Storing the Machine 25
Replacing the Depth Wheel 26
Replacing the Skirt 26
Replacing the Cutting Blade 27
Checking and Replacing the Wear
Guard 27
Maintenance and Care 28
Main Parts 30
Specifications 32
Maintenance and Repairs 32
Disposal 33
STIHL Incorporated Federal
Emission Control Warranty
Statement 33
STIHL Incorporated California
Exhaust and Evaporative
Emissions Control Warranty
Statement 35
Trademarks 37
FC 90
English
2
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.
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:
NA 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:
NLoosen the screw (1).
NLever (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 an imminent risk of severe or
fatal injury.
WARNING
Indicates a hazardous situation which, if
not avoided, could result in severe or
fatal injury.
NOTICE
Indicates a risk of property damage,
including damage to the machine or its
individual components.
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.
Guide to Using this Manual
Fuel tank for gasoline
and engine oil mixture
Press to operate decom-
pression valve
Manual fuel pump
Press to operate manual
fuel pump
Filler hole for gear
lubricant
Air intake summer mode
Air intake winter mode
Handle heating
FC 90
English
3
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 handle,
harness and deflector. Use only cutting
attachments that are specifically
authorized by STIHL for use on your FC
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.
Use your edger only for edging in grass,
weeds and soft green plants.
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
edgers. Different models may have
different parts and controls. See the
appropriate section of your instruction
manual for a description of the controls
and function of the parts of your model.
Safe use of an edger 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.
Safety Precautions and
Working Techniques
Because an edger 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.
FC 90
English
4
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
Be particularly alert and cautious when
wearing hearing protection because
your ability to hear warnings (shouts,
alarms, etc.) is restricted.
To reduce the risk of
injury to your eyes never
operate your power tool
unless wearing goggles
or properly fitted protec-
tive glasses with
adequate top and side
protection complying with
ANSI Z87 "+" (or your
applicable national stand-
ard). If there is a risk of
injury to the operator´s
face, STIHL also recom-
mends that you also wear
a face shield or face
screen over your gog-
gles or protective
glasses.
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.
Wear an approved safety
hard hat to reduce the
risk of injury to your head
when there is a danger of
head injuries.
FC 90
English
5
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.
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.
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 attachment has
stopped before putting an edger 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" of your instruction
manual.)
WARNING
Fueling Instructions
WARNING
To reduce the risk of serious injury from
burns, never attempt to refuel the unit
until it has been completely removed
from the operator.
Always wear heavy duty
work gloves (e.g. made of
leather or other wear
resistant material) when
handling the machine
and metal blades. Heavy-
duty, 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.
Good footing is very
important. Wear sturdy
boots with nonslip soles.
Steel-toed safety boots
are recommended.
Gasoline is an extremely
flammable fuel. If spilled
and ignited by a spark or
other ignition source, it
can cause fire and seri-
ous 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 combusti-
ble fuel vapor may
escape from the fuel
system.
FC 90
English
6
WARNING
Fuel your power tool 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 conditions
and the tank venting system.
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
WARNING
In order to reduce the risk of fuel spillage
and fire from an improperly tightened
fuel cap, correctly position and tighten
the fuel cap in the fuel tank opening.
Different models may be equipped with
different fuel caps.
Toolless cap with grip
To do this with this STIHL cap, raise the
grip on the top of the cap until it is upright
at a 90° angle. Insert the cap in the fuel
tank opening with the raised positioning
marks on the grip of the cap and on the
fuel tank opening lining up. Using the
grip, press the cap down firmly while
turning it clockwise as far as it will go
(approx. 1/4 turn).
Misaligned, damaged or broken cap
NIf the cap does not drop fully into the
opening when the positioning marks
line up and/or if the cap does not
tighten properly when twisted, the
base of the cap may be prematurely
rotated (in relation to the top) to the
closed position. Such misalignment
can result from handling, cleaning
or an improper attempt at
tightening.
NTo return the cap to the open
position for installation, turn the cap
(with the grip up) until it drops fully
into the tank opening. Next, twist the
cap counterclockwise as far as it will
go (approx. 1/4 turn) – this will twist
Check for fuel leakage
while refueling and during
operation. If fuel leakage
is found, do not start or
run the engine until the
leak is fixed and any
spilled fuel has been
wiped away. Take care
not to get fuel on your
clothing. If this happens,
change your clothing
immediately.
Fold the grip flush with
the top of the cap. Grip
the cap and check for
tightness. If the grip does
not lie completely flush
with the cap and the
detent on the grip does
not fit in the correspond-
ing recess in the filler
opening, or if the cap is
loose in the filler opening,
the cap is not properly
seated and tightened and
you must repeat the
above steps.
001BA220 KN
Left: Base of cap in closed posi-
tion (with open space)
Right: Base of cap correctly posi-
tioned for installation
001BA227 KN
001BA226 KN
FC 90
English
7
the base of the cap into the correct
position. Then, twist the cap
clockwise, closing it normally.
NIf your cap still does not tighten
properly, it may be damaged or
broken; immediately stop use of the
unit and take it to your authorized
STIHL dealer for repair.
Screw Cap
WARNING
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). Do not start the engine if there
are leaks or damage – risk of fire! 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.
WARNING
The cutting attachment 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
damaged blades 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
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".)
Adjust carrying harness and hand grip to
suit your size before starting work. The
machine should be properly balanced as
specified in your instruction manual for
proper control and less fatigue in
operation. To be better prepared in case
of an emergency, practise releasing the
unit from the harness as quickly as
possible.
Unit vibrations can cause
an improperly tightened
fuel filler cap to loosen or
come off and spill quanti-
ties of fuel. In order to
reduce the risk of fuel
spillage and fire, tighten
the fuel filler cap by hand
as securely as possible.
To reduce the risk
of personal injury
to the operator
from blade con-
tact and thrown
objects, make sure
your unit is
equipped with the
proper deflector,
handle and
harness.
239BA011 KN
FC 90
English
8
Starting
WARNING
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.
With the engine running only at idle,
attach the power tool to the spring hook
of your harness (see appropriate
chapter of this manual.)
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.
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 rewind it properly.
Failure to follow this procedure may
result in injury to your hand or fingers
and may damage the starter
mechanism.
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 your
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.
Your right hand should grip the rear
handle. This also applies to left-handers.
WARNING
To reduce the risk of injury from loss of
control, never work on a ladder or on any
other insecure support. Never hold the
cutting attachment above waist height.
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 attach-
ment. Never touch a
moving cutting attach-
ment with your hand or
any other part of your
body.
002BA054 KN