Instruction Manual
Table Of Contents
- STIHL FS 91, 91 R
- 1 Guide to Using this Manual
- 2 Safety Precautions and Working Techniques
- 2.1 Clothing and equipment
- 2.2 Transporting the machine
- 2.3 Refueling
- 2.4 Before starting
- 2.5 Starting the engine
- 2.6 Holding and guiding the machine
- 2.7 While working
- 2.8 Using mowing heads
- 2.9 When using metal cutting attachments
- 2.10 Vibrations
- 2.11 Maintenance and Repairs
- 2.12 Symbols on Deflectors
- 2.13 Shoulder Strap/Harness
- 2.14 Mowing Head with Nylon Line
- 2.15 STIHL Polycut Mowing Head with Polymer Blades
- 2.16 Risk of Kickout (Blade Thrust) with Metal Cutting Attachments
- 2.17 Grass Cutting Blade
- 2.18 Brush Knife
- 2.19 Circular Saw Blade
- 3 Approved Combinations of Cutting Attachment, Deflector, Handle and Harness
- 4 Approved Power Tool Attachments
- 5 Mounting the Bike Handle
- 6 Mounting the Loop Handle
- 7 Adjusting the Throttle Cable
- 8 Fitting the Carrying Ring
- 9 Mounting the deflector
- 10 Mounting the Cutting Attachment
- 10.1 Placing power tool on the ground
- 10.2 Mounting Hardware for Cutting Attachments
- 10.3 Blocking the Shaft
- 10.4 Removing the Mounting Hardware
- 10.5 Mounting the Cutting Attachment
- 10.6 Fitting Mowing Head with Screw Mounting
- 10.7 Remove the mowing head.
- 10.8 Mounting Metal Cutting Attachments
- 10.9 Removing the Metal Cutting Attachment
- 11 Fuel
- 12 Fueling
- 13 Fitting the Harness
- 14 Balancing the Machine
- 15 Starting / Stopping the Engine
- 16 Transporting the Unit
- 17 Operating Instructions
- 18 Replacing the Air Filter
- 19 Adjusting the Carburetor
- 20 Spark Arresting Screen in Muffler
- 21 Spark Plug
- 22 Engine Running Behavior
- 23 Lubricating the Gearbox
- 24 Storing the Machine
- 25 Sharpening Metal Cutting Blades
- 26 Maintaining the Mowing Head
- 27 Maintenance and Care
- 28 Minimize Wear and Avoid Damage
- 29 Main Parts
- 30 Specifications
- 31 Maintenance and Repairs
- 32 Disposal
- 33 EC Declaration of Conformity
–
Use only an approved combination of cutting
attachment, deflector, handle and harness. All
parts must be assembled properly and
securely
–
The stop switch must be easy to push
–
Check the choke lever, throttle trigger and
throttle trigger lockout for smooth action -
throttle trigger must return automatically to idle
position. The choke lever must spring back
from the g and < positions to the run posi‐
tion F when the throttle trigger lockout and
throttle trigger are squeezed
–
Check that the spark plug boot is secure – a
loose boot may cause sparking that could
ignite combustible fumes and cause a fire!
–
Cutting attachment or interchangeable attach‐
ment: correctly fitted, secure and in perfect
condition
–
Safety devices (e. g., deflector for cutting
attachments, rider plate) for damage and/or
wear. Always replace damaged parts. Do not
use the machine with a damaged deflector or
worn rider plate (if the writing and arrows are
no longer discernible)
–
Never attempt to modify the controls or safety
devices
–
Keep the handles dry and clean – free from oil
and dirt – this is important for safe control of
the machine
–
Adjust the harness and handle(s) to suit your
height and reach. Observe the chapter "Fitting
the Harness" – "Balancing the machine"
To reduce the risk of personal injury, do not
operate your power tool if it is damaged or not
properly assembled!
To prepare for emergencies when using a har‐
ness: Practice setting down the machine quickly.
To avoid damage, do not throw the unit to the
ground when practicing.
2.5 Starting the engine
Start the engine at least 3 meters from the fuel‐
ing spot, outdoors only.
Place the unit on firm ground in an open area.
Make sure you have good balance and secure
footing. Hold the unit securely. The cutting
attachment must be clear of the ground and all
other obstructions because it may begin to run
when the engine starts.
This is a one-person machine – ensure that there
is no-one within 15 meters of the machine, not
even when starting the power tool! Risk of injury
due to ejected objects!
Avoid contact with the cutting attach‐
ment – risk of injury!
Do not drop-start the power tool –
start the engine as described in the
User Manual. The cutting attachment
runs on for a short while after releas‐
ing the throttle trigger – coasting
effect!
Check engine idling: The cutting attachment
must remain at a standstill when the engine idles
– throttle trigger released.
Keep easily combustible materials (e. g., wood
chips, bark, dry grass, fuel) away from hot
exhaust gases and hot muffler surfaces – risk of
fire!
2.6 Holding and guiding the
machine
Always hold the unit firmly with both hands on
the handles.
Make sure you always have good balance and
secure footing.
2.6.1 For versions with bike handle
002BA055 KN
Right hand on control handle, left hand on grip
on handlebar.
2.6.2 For versions with loop handle
002BA080 KN
For versions with loop handle and loop handle
with barrier bar, left hand on the loop handle,
2 Safety Precautions and Working Techniques
English
0458-426-8321-B 5