Stihl Fs 80 R Owners Manual

							
Instruction Manual    
Manual de instrucciones
STIH)
STIHL FS 80, 85
BA_FS80_30_U_K4.book  Seite 0  Freitag, 8. Oktober 2004  10:59 10
Warning!
Read and follow all safety precautions in 
Instruction Manual – improper use can cause 
serious or fatal injury.
Advertencia!
Lea y siga todas las precauciones de 
seguridad dadas en el manual de 
instrucciones – el uso incorrecto puede 
causar lesiones graves o mortales. 
						

							
1
FS 80, FS 80 R, FS 85, FS 85 R English / USA
BA_SE_039_010_01_19.fm
Printed on chlorine-free paper.
Printing inks contain vegetabl e oils; paper can be recycled.
© ANDREAS STIHL AG & Co. KG, 2008
 
0458 393 8621. M10. D8 . CP. Printed in USA 
STIHl
Contents
Guide to Using this Manual  ..............  2
Safety Precautions and 
Working Techniques  .........................  3
Approved Combinations of 
Cutting Tool, Deflector, 
Handle and Harness  .......................  20
Approved Power 
Tool Attachments  ............................  22
Mounting the Bike Handle  ..............  22
Adjusting the Throttle Cable  ...........  24
Mounting the Loop Handle  .............  24
Fitting the Carrying Eye  ..................  26
Mounting the Deflector  ...................  26
Mounting the Cutting Tools  .............  27
Fuel ................................................  31
Fueling ............................................  32
Fitting the Harness  .........................  33
Balancing the Brushcutter  ..............  33
Starting / Stopping 
the Engine  ......................................  35
Operating Instructions  ....................  38
Cleaning the Air Filter  .....................  38
Motor Management  ........................  39 Adjusting the Carburetor  ................  39
Spark Arresting Screen 
in Muffler  ........................................  41
Checking the Spark Plug  ................  41
Lubricating the Gearbox  .................  42
Replacing the Starter Rope 
and Rewind Spring  .........................  42
Storing the Machine  .......................  45
Sharpening 
Metal Cutting Tools .........................  45
Maintenance Chart  .........................  47
Parts and Controls  .........................  49
Specifications .................................  51
Special Accessories  .......................  52
Maintenance and Repairs  ..............  53
STIHL Incorporated 
Federal Emission Control 
Warranty Statement ........................  54
STIHL Incorporated 
California Exhaust and
Evaporative Emissions Control 
Warranty Statement ........................  56
Trademarks ....................................  58Allow only persons who understand this 
manual to operate your trimmer/
brushcutter. 
To receive maximum performance and 
satisfaction from your STIHL trimmer/
brushcutter, it is important that you read 
and understand the maintenance and 
safety precautions, starting on page 3, 
before using your trimmer/brushcutter. 
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 trimmer/brushcutter 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, handle and harness for the 
type of cutting attachment being used. 
Always wear proper eye protection.
STIHLs philosophy is to continually 
improve all of its products. As a result, 
engineering changes and improve-
ments are made from time to time. If  the 
operating characteristics or the appear-
ance of  your trimmer/brushcutter differs 
from those described in this manual, 
please contact your STIHL dealer for 
information and assistance. 
						

							
2 English / USAFS 80, FS 80 R, FS 85, FS 85 R
Pictograms
All the pictograms attached to the 
machine are shown and explained in  
this manual.
The operating and handling instructions 
are supported by illustrations.
Symbols in text
The individual steps or procedures 
described in the manual may be marked 
in different ways:
:A bullet marks a step or procedure 
without direct reference to an 
illustration. 
A description of a step or procedure that 
refers directly to an illustration may 
contain item numbers that appear in the 
illustration.
Example:
Loosen the screw ( 1) 
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 described below:
Warning where there is a risk of an 
accident or personal injury or 
serious damage to property.
Caution where there is a risk of 
damaging the machine or its 
individual components.
Note or hint which is not essential 
for using the machine, but may 
improve the operator’s under-
standing of the situation and result 
in better use of the machine.
Note or hint on correct procedure in 
order to avoid damage to the 
environment.
Equipment and features
This instruction manual may refer to 
several models with different 
features. Components that are not 
installed on all models and related 
applications are marked with an 
asterisk (*).  Such components may 
be available as special accessories 
from your STIHL dealer.
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. If the 
operating characteristics or the 
appearance of your machine differ from 
those described in this manual, please 
contact your STIHL dealer for 
assistance.
Therefore some changes, modifications 
and improvements may not be covered 
in this manual.
Guide to Using this Manual 
						

							
3
FS 80, FS 80 R, FS 85, FS 85 R English / USA
Because a trimmer/
brushcutter is a high-
speed, fast-cutting power 
tool sometimes equipped 
with sharp cutting blades, 
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.
The terminology utilized in this manual 
when referring to the power tool reflects 
the fact that different types of cutting 
attachments may be mounted on it. The 
term trimmer is used to designate an 
FS unit that is equipped with a nylon line 
head or a head with flexible plastic 
blades (i.e., the PolyCut head). A 
brushcutter designates a unit 
equipped with a rigid metal blade. Many 
FS models may be used as either a 
trimmer or a brushcutter - therefore, the 
power tool is referred in this manual as a 
trimmer/brushcutter. Some smaller 
and/or lightweight FS models may only 
be used as a trimmer, i.e., they may not 
be used with metal blades.  The term clearing saw indicates a 
high-powered trimmer/brushcutter that 
is particularly suited for use with a 
circular saw blade to clear saplings or 
small trees. FS models with an R on 
the nameplate were originally 
configured (at the time of distribution) as 
a trimmer with a loop handle.
!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 for the type of 
cutting attachment you are using. Use 
only cutting attachments that are 
specifically authorized by STIHL for use 
on your FS 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 line or 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 
heads or blades, may result in serious or 
fatal injury to the operator or bystanders.
STIHL does not recommend the use of 
rigid blades when cutting in stony areas. 
Use your trimmer/brushcutter equipped 
with the appropriate cutting attachment 
only for cutting grass, brush, wood and 
similar material. It must not be used for 
any other purposes, since such misuse 
may result in an accident or 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.
Safety Precautions and 
Working Techniques 
						

							
4 English / USAFS 80, FS 80 R, FS 85, FS 85 R
!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 
trimmer/brushcutters. Different models 
may have different parts and controls. 
See the appropriate section of your 
instruction manual for a description of 
the controls and the function of the parts 
of your model.
Safe use of a trimmer/brushcutter 
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 (Raynauds phenomenon) or 
carpal tunnel syndrome. 
These conditions reduce the hands 
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 white-
finger 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 
operators hands. An AV system is 
recommended for those persons using 
power tools on a regular or sustained 
basis. 
						

							
5
FS 80, FS 80 R, FS 85, FS 85 R English / USA
Keep the AV system well maintained. A 
power tool with loose components or 
with damaged or worn AV buffers will 
tend to have higher vibration levels.
Maintain a firm grip at all times, but do 
not squeeze the handles with constant, 
excessive pressure. Wear gloves and 
keep your hands warm. 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 
Z 87.1 (or your applicable national 
standard). To reduce the risk of injury to 
your 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.
Always wear gloves 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.  
						

							
6 English / USAFS 80, FS 80 R, FS 85, FS 85 R
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 and Controls.”
!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. For the 
cutting attachments authorized by 
STIHL for your unit, see the chapter 
“Approved Combinations of Cutting 
Attachment, Deflector, Handle and 
Harness“ in the instruction manual or the 
STIHL “Power Tools and Accessories“ 
catalog.
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 or line 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.
389BA019 KN 
						

							
7
FS 80, FS 80 R, FS 85, FS 85 R English / USA
!Warning!
Always shut off the engine and make 
sure the cutting attachment has stopped 
before putting a trimmer/brushcutter 
down. When transporting it in a vehicle, 
properly secure it to prevent turnover, 
fuel spillage and damage to the unit. 
STIHL recommends that you keep metal 
blades covered with the transport guard 
(optional accessory).
Fuel
Your STIHL power tool uses an oil- 
gasoline mixture for fuel (see the chap-
ter on “Fuel” of your instruction manual).
!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.
Fueling Instructions 
!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, 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 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. 
Different models may be equipped with 
different fuel caps. Cap with grip
!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.
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 
triangular marks on the grip of the cap 
and on the fuel tank opening lining up. 
Using the grip, turn the cap firmly 
clockwise as far as it will go (approx. a 
quarter turn).
Fold the grip flush with the 
top of the cap. If the grip 
does not lie completely 
flush with the cap and the 
detent on the grip does 
not fit in the 
corresponding recess in the filler neck, 
the cap is not properly seated and 
tightened and you must repeat the 
above steps. 
						

							
8 English / USAFS 80, FS 80 R, FS 85, FS 85 R
Screw cap
!Warning!
Unit vibrations can cause 
an improperly tightened 
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.
Before Starting
!Warning!
Always check your power tool for proper 
condition and operation before starting, 
particularly the throttle trigger, throttle 
trigger interlock, stop switch, cutting 
attachment, 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!
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 or head 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 or 
damaged heads or cracked, bent, 
warped or damaged blades. Replace 
damaged heads or blades before using 
the power tool. Always keep blades 
sharp. 
Keep the handles clean and dry at all 
times; it is particularly important to keep 
them free of moisture, pitch, oil, 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 or line 
contact and 
thrown objects, make sure your unit is 
equipped with the proper deflector, 
handle and harness for the type of 
cutting attachment being used (see 
chart in the chapter on Approved 
Combinations of Cutting Attachment, 
Deflector, Handle and Harness).
As can be seen in that chart, some 
cutting attachments may require you to 
change your deflector, handle and/or 
harness.
Keep the deflector (and the attached 
skirt where appropriate) adjusted 
properly at all times (see chapters on 
Mounting the Deflector and Mounting 
the Cutting Attachments of your 
instruction manual). 
						

							
9
FS 80, FS 80 R, FS 85, FS 85 R English / USA
.
Arrows on the deflector 
(A) and limit stop 
(B)  (as seen from the underside)  show 
the correct direction of rotation of the 
cutting attachment. When viewed from 
above, however, the cutting attachment 
rotates  counterclockwise.
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, practice releasing the 
unit from the harness as quickly as 
possible. 
Starting
Start the engine at least 10 feet 
(3 meters) 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 or 
line 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.
A
000BA006 KN
B
000BA007 KN