STIHL BT 131
Instruction Manual
Notice d’emploi
G Instruction Manual
1 - 26
F Notice d’emploi
27 - 55
Contents
English
Guide to Using this Manual 2
Safety Precautions and Working
Techniques 2
Assembling the Unit 7
Adjusting the Throttle Cable 8
Fuel 8
Fueling 10
Auger Brake 10
Original Instruction ManualPrinted on chlorine-free paper
Fitting the Auger 11
Starting / Stopping the Engine 12
Operating Instructions 14
Releasing a Trapped Auger 14
Replacing the Air Filter 15
Engine Management 15
Adjusting the Carburetor 16
Spark Arresting Screen in Muffler 16
Spark Plug 16
Engine Running Behavior 17
Lubricating the Gearbox 18
Storing the Machine 18
Maintenance and Care 19
Main Parts 21
Printing inks contain vegetable oils, paper can be recycled.
Specifications 22
Maintenance and Repairs 23
Disposal 24
STIHL Limited Emission Control
Warranty Statement 24
Dear Customer,
Thank you for choosing a quality
engineered STIHL product.
It has been built using modern
production techniques and
comprehensive quality assurance.
Every effort has been made to ensure
your satisfaction and trouble-free use of
the product.
Please contact your dealer or our sales
company if you have any queries
concerning this product.
Your
Dr. Nikolas Stihl
© ANDREAS STIHL AG & Co. KG, 2020
0458-529-8221-A. VA3.E20.
0000007599_004_GB
BT 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 the machine are explained in
this manual.
Depending on the model concerned, the
following pictograms may be attached to
your machine.
Fuel tank; fuel mixture of
gasoline and engine oil
Operate manual fuel
pump
Auger brake
Symbols in text
WARNING
Warning where there is a risk of an
accident or personal injury or serious
damage to property.
NOTICE
Caution where there is a risk of
damaging the machine or its individual
components.
Engineering improvements
STIHL's philosophy is to continually
improve all of its products. For this
reason we may modify the design,
engineering and appearance of our
products periodically.
Therefore, some changes, modifications
and improvements may not be covered
in this manual.
Safety Precautions and
Working Techniques
Special safety precau
tions must be observed
when working with this
power tool because of its
high torque and the high
speed of the auger bit in
certain applications, and
because the auger bits
have sharp edges.
It is important you read
and understand the
instructions for use
before first use and keep
it in a safe place for future
reference. Non-compli
ance with the User
Manual may cause seri
ous or even fatal injury.
Observe all applicable local safety
regulations, e.g. by trade organizations,
social insurance institutions, labor safety
authorities etc.
If you have never used a power tool
before: Have your dealer or other
experienced user show you how to
operate your machine – or attend a
special course to learn how to operate it.
Minors are not allowed to work with the
power tool – except adolescents above
16 years of age who are instructed
under supervision.
Children, animals and bystanders must
not be allowed near the machine.
When not using the machine, it must be
laid down in such a way that it does not
endanger anyone. Ensure that the
machine cannot be used without
authorization.
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BT 131
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The user is responsible for accidents or
risks involving third parties or their
property.
Do not lend or rent your power tool
without the User Manual. Be sure that
anyone using it understands the
information contained in this manual.
The use of machines that emit noise
may be limited to certain hours of the
day as specified by national and/or
regional or local regulations.
Anyone operating the machine must be
well rested, in good physical health and
in good mental condition.
If you have any condition that might be
aggravated by strenuous work, check
with your doctor before operating a
machine.
If you have a pacemaker: The ignition
system of your machine produces an
electromagnetic field of very low
intensity. This field may interfere with
some pacemakers. STIHL recommends
that persons with pacemakers consult
their physician and the pacemaker
manufacturer to reduce any health risk.
Anyone who has consumed alcohol or
drugs or medicines affecting their ability
to react must not operate a power tool.
Use your power tool only for drilling
holes in soil, ice and wood – depending
on the drilling tool mounted. Select the
drill axis so that the lever of the drill
brake can be supported on the thigh of
the operator at any time during drilling.
It must not be used for any other
purposes.
Before drilling, make sure that there are
no lines (e. g. for gas, water, electricity)
at the drilling sites:
– Obtain information from the local
utility companies
– If in doubt, check the existence of
lines with detectors or test
excavations
Only use augers or accessories which
have been approved by STIHL for this
machine or which are technically
equivalent. If you have any questions in
this respect, consult your dealer. Use
only high quality parts and accessories.
in order to avoid the risk of accidents
and damage to the machine.
STIHL recommends the use of original
STIHL tools and accessories. They are
specifically designed to match the
product and meet your performance
requirements.
Never attempt to modify your power tool
in any way since this may increase the
risk of personal injury. STIHL excludes
all liability for personal injury and
damage to property caused while using
unauthorized attachments.
Do not use a high-pressure washer to
clean the power tool. The solid jet of
water may damage parts of the unit.
Clothing and equipment
Wear proper protective clothing and
equipment.
Clothing must be sturdy
but allow complete free
dom of movement. Wear
close-fitting clothes such
as a boiler suit, not a
loose jacket.
Do not wear clothing which could
become trapped in wood, brush or
moving parts of the machine. Do not
wear a scarf, necktie or jewelry.
Tie up and confine long
hair above your
shoulders.
Wear sturdy shoes with
non-slip soles.
WARNING
To reduce the risk of eye
injuries, wear close-fit
ting safety glasses in
accordance with Euro
pean Standard EN 166.
Make sure the safety
glasses are a snug fit.
Wear hearing protection, e.g. ear
defenders.
Wear a safety hard hat where there is a
danger of head injuries from falling
objects.
Wear sturdy protective
gloves made of a resist
ant material (e. g.
leather).
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English
STIHL can supply a comprehensive
range of personal protective equipment.
Transporting the machine
Always stop the engine.
Remove the auger before transporting
the power tool long distances. To reduce
the risk of burn injury, carry the unit by
the handle frame with hot parts of the
machine (e.g. gearbox) away from your
body.
By vehicle: When transporting in a
vehicle, properly secure your machine to
prevent turnover, damage and fuel
spillage.
Refueling
Gasoline is highly flam
mable – keep away from
fire or flame – do not spill
any fuel – no smoking.
Always shut off the engine before
refueling.
Do not fuel a hot engine – fuel may spill
and cause a fire!
Open the fuel cap carefully to allow any
pressure build-up in the tank to release
slowly and avoid fuel spillage.
Only refuel the machine in a well
ventilated place. If fuel has been spilled,
immediately clean the machine – do not
allow your clothes to be splashed with
fuel. If that happens, change your
clothes at once.
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After fueling, tighten
down the screw-type fuel
cap as securely as
possible.
This helps reduce the risk of unit
vibrations causing an incorrectly
tightened fuel cap to loosen or come off
and spill quantities of fuel.
Check for fuel leakage!
Never start the engine if
fuel has been spilled or is
leaking – Fatal burns may
result!
Before starting
Check that your power tool is properly
assembled and in good condition – refer
to appropriate chapters in the
instructions for use.
– Check the fuel system for leaks,
especially the visible parts, e. g.,
fuel cap, hose connections, manual
fuel pump (only in machines with a
manual fuel pump). In case of
leakage and damage, do not start
the engine – risk of fire! Have the
machine serviced by a dealer
before using it
– The stop switch must be easy to
push
– Functional drill brake
– 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 position F when
the throttle trigger lockout and
throttle trigger are squeezed
– Check that the spark plug boot is
secure – a loose boot may cause
arcing that could ignite combustible
fumes and cause a fire!
– 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
To reduce the risk of personal injury, do
not operate your power tool if it is
damaged or not properly assembled!
Starting the engine
Start the engine at least 3 meters from
the fueling spot, outdoors only.
Place the power tool on level ground,
make sure you have secure footing.
Engage the drill brake before starting.
Otherwise, the drilling tool may begin to
run, causing the user to lose control of
the earth auger.
The machine is operated by a single
person only – do not allow any person to
stay within the working area – nor with
starting.
To reduce the risk of injury, avoid
contact with the drilling tool.
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9912BA000 KN
Do not drop-start the engine – start it as
described in the instructions for use.
Check idle speed setting: The drilling
tool must not rotate when the engine is
idling with the throttle trigger released.
Keep easily combustible materials (e.g.,
wood chips, bark, dry grass, fuel) away
from hot exhaust gases and the hot
muffler surface – risk of fire!
Holding and guiding the machine
Always hold the unit firmly with both
hands on the handles.
Ensure you always have a firm and safe
footing – drill brake on left thigh.
Firmly grasp the handles with the
thumbs, left hand on control handle.
While working
Make sure you always have good
balance and secure footing.
In the event of impending danger or in
an emergency, switch off the engine
immediately by pressing the stop switch.
Do not allow any other persons in the
work area. Keep well away from other
people – risk of accidents!
Check for correct idling, so that the
auger stops turning when the throttle
trigger is released.
Check and correct the idle speed setting
at regular intervals. If the drilling tool
continues to rotate when the engine is
idling, have the machine checked by
your servicing dealer. STIHL
recommends STIHL dealers.
Take special care in slippery conditions
– dampness, snow, ice, on slopes or
uneven ground.
Watch out for obstacles: tree stumps,
roots – risk of tripping or stumbling!
Be particularly alert and cautious when
wearing hearing protection because
your ability to hear warnings (shouts,
alarms, etc.) is restricted.
Take breaks when you start getting tired
or feeling fatigue – risk of accidents!
Work calmly and carefully – in daylight
conditions and only when visibility is
good. Proceed with caution, do not put
others in danger.
As soon as the engine is
running, the power
machine generates toxic
exhaust gas. These
gases may be odorless
and invisible and may
contain unburned hydro
carbons and benzene.
Never run the engine
indoors or in poorly venti
lated locations, even if
your model is equipped
with a catalytic converter.
To reduce the risk of serious or fatal
injury from breathing toxic fumes,
ensure proper ventilation when working
in trenches, hollows or other confined
locations. This reduces the risk of
serious or fatal injury from breathing
toxic fumes.
Stop work immediately if you start
suffering from nausea, headaches,
impaired vision (e.g. your field of vision
gets smaller), impaired hearing,
dizziness, or impaired concentration –
these symptoms may possibly be the
result of too-high exhaust gas
concentration – Risk of accidents!
Operate your power tool so that it
produces a minimum of noise and
emissions – do not run the engine
unnecessarily, accelerate the engine
only when working.
To reduce the risk of fire, do not smoke
while operating or standing near your
power tool. Combustible fuel vapor may
escape from the fuel system.
Dust, fumes and smoke produced while
working may be hazardous to your
health. Wear respiratory protection in
case of heavy dust or smoke emission.
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If your power 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 – see also
"Before Starting".
Check in particular that the fuel system
has no leaks and the safety equipment is
fully operative. Never use a power tool
that is no longer safe to operate. In case
of doubt, contact a dealer.
Do not operate your power tool in the
starting throttle position – engine speed
cannot be controlled in this position.
To reduce the risk of injury, do not touch
the drilling tool and drilling spindle
unless the engine is stopped and the
drilling tool is at a standstill.
Avoid contact with lines
carrying electrical cur
rent – Risk of electrical
shock!
Hold the machine firmly so that sudden
jolts can be absorbed – only apply a
small amount of pressure when drilling.
Take particular care
when working in stony
areas or ground with
roots.
Cover drilled holes and secure them.
To reduce the risk of injury, shut off the
engine and engage the drill brake before
changing the drill.
Do not touch machine parts, particularly
the muffler – Risk of burn injuries.
Always shut off the engine before
leaving the unit unattended.
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Check drilling tools at regular short
intervals during operation or
immediately if there is a noticeable
change in operating behavior. Replace
damaged or dull drilling tools and blades
immediately.
Vibrations
Prolonged use of the power tool may
result in vibration-induced circulation
problems in the hands (whitefinger
disease).
No general recommendation can be
given for the length of usage because it
depends on several factors.
The period of usage is prolonged by:
– Hand protection (wearing warm
gloves)
– Work breaks
The period of usage is shortened by:
– Any personal tendency to suffer
from poor circulation (symptoms:
frequently cold fingers, tingling
sensations).
– Low outside temperatures.
– The force with which the handles
are held (a tight grip restricts
circulation).
Continual and regular users should
monitor closely the condition of their
hands and fingers. If any of the above
symptoms appear (e.g. tingling
sensation in fingers), seek medical
advice.
Maintenance and Repairs
Service the machine regularly. Do not
attempt any maintenance or repair work
not described in the instruction manual.
Have all other work performed by a
servicing dealer.
STIHL recommends that you have
servicing and repair work carried out
exclusively by an authorized STIHL
servicing dealer. STIHL dealers are
regularly given the opportunity to attend
training courses and are supplied with
the necessary technical information.
Only use high-quality replacement parts
in order to avoid the risk of accidents
and damage to the machine. If you have
any questions in this respect, consult a
servicing dealer.
STIHL recommends the use of original
STIHL replacement parts. They are
specifically designed to match your
model and meet your performance
requirements.
To reduce the risk of injury from
unintentional engine startup, always
shut off the engine and disconnect the
spark plug boot before performing any
repairs, maintenance or cleaning work. –
Exception: Carburetor and idle speed
adjustments.
Do not turn the engine over on the
starter with the spark plug boot or spark
plug removed since there is otherwise a
risk of fire from uncontained sparking.
To reduce the risk of fire, do not service
or store your machine near open flames.
Check the fuel filler cap for leaks at
regular intervals.
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3
2
3
1
9912BA001 KN
9912BA002 KN
3
3
9912BA003 KN
Use only a spark plug of the type
approved by STIHL and make sure it is
in good condition – see "Specifications".
Inspect the ignition lead (insulation in
good condition, secure connection).
Check the condition of the muffler.
To reduce the risk of fire and damage to
hearing, do not operate your machine if
the muffler is damaged or missing. –
Do not touch a hot muffler since burn
injury will result.
Vibration behavior is influenced by the
condition of the AV elements – check the
AV elements at regular intervals.
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.
For any maintenance please refer to the
maintenance chart and to the warranty
statement near the end of the instruction
manual.
Assembling the Unit
Fitting activating lever for auger brake
N Insert the activating lever (1) into
the clamp
N Place the holder (2) onto the
activating lever
N Screw in the fastening screws (3)
and tighten
Fit the padding
N Hook the padding (1) with the
tabs (2) into the oblong holes in the
handle frame
N Fold up the padding
N Secure the padding to the
handlebar with the cling strips (3) –
do not jam the throttle cable
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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
machine is completely and properly
assembled.
N Set the throttle trigger to the full
throttle position.
N Rotate the screw in the throttle
trigger clockwise 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.
NOTICE
Fuel with an octane rating below 89 may
increase engine temperatures. This, in
turn, increases the risk of piston seizure
0000-GXX-2145-A0
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!
NOTICE
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 an incorrect idle adjustment. At
correct idle speed, the cutting tool
should not move.
If your machine’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 a
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. To help your engine run
cleaner and reduce harmful carbon
deposits, STIHL recommends using
STIHL HP Ultra 2-cycle engine oil or ask
your dealer for an equivalent fully
synthetic 2-cycle engine oil.
To meet the requirements of EPA and
CARB we recommend to use STIHL HP
Ultra oil.
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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
If not using MotoMix, use only STIHL
two-stroke engine oil or equivalent highquality two-stroke engine oils that are
designed for use in air cooled two-cycle
engines.
The use of non-seasonal gasoline
blends may increase the potential for
pressure to build in the fuel tank during
operation. For example, using a winter
blend during the summer will increase
pressure in the fuel tank. Always use
gasoline blends appropriate to the
season, altitude and other
environmental factors.
Do not use NMMA 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.).
WARNING
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.
Fuel mix ages
If not using 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 by hand to ensure proper mix of oil and
gasoline.
WARNING
Shaking fuel can cause pressure to build
in the fuel container. To reduce the risk
of fire and severe personal injury or
property damage from fuel spraying,
allow the fuel container to sit for several
minutes before opening. Open the
container slowly to release any residual
pressures. Never open the fuel
container in the vicinity of any ignition
source. Read and follow all warnings
and instructions that accompany your
fuel container.
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Gaso
line
US gal. US fl.oz.
12.6
2 1/2 6.4
5 12.8
Oil (STIHL 50:1 or equiva
lent high-quality oils)
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Dispose of empty mixing-oil containers
only at authorized disposal locations.
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0000-GXX-0476-A0
002BA447 KN
002BA448 KN
0000-GXX-1860-A0
A
Fueling
Preparations
N Before fueling, clean the filler cap
and the area around it to ensure that
no dirt falls into the tank.
N Position the machine so that the
tank cap faces up.
Opening the Tank Cap
N Turn the cap counterclockwise until
it can be removed from the tank
opening.
N Remove the tank cap.
Filling Up with Fuel
Take care not to spill fuel while fueling
and do not overfill the tank.
STIHL recommends you use the STIHL
filler nozzle for fuel (special accessory).
N Fill up with fuel.
Closing the Tank Cap
N Place the cap in the opening.
N Turn the cap clockwise as far as
stop and tighten it down as firmly as
possible by hand.
Auger Brake
Engaging the Auger Brake
N Move the activating lever to
position A .
– when starting
– at idling speed
– to unwind a trapped auger
If the auger snags on an obstacle in the
hole (e.g. roots or stones) the machine
will begin to turn counterclockwise – the
activating lever is pressed against the
operator's thigh and thus engages the
auger brake.
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0000-GXX-1861-A0
B
9912BA010 KN
1
2
3
3
Disengaging the Auger Brake
N Move the activating lever to
position B
Checking Operation of Auger Brake
The auger brake is subject to normal
wear and tear. Regularly check that it is
operating properly before you start work
and after releasing a trapped auger.
Before starting work and after releasing
a trapped auger
N With the engine running at idle
speed, engage the auger brake and
then open the throttle wide for no
more than 3 seconds – the auger
must not rotate.
If the auger brake fails, have it repaired
immediately by your dealer – STIHL
recommends that this work be
performed by a STIHL servicing dealer.
Fitting the Auger
N Shut off the engine and engage the
auger brake – see "Auger Brake".
N Put the machine down.
N Pull the retaining pin (1) out of the
auger's shank.
N Push the auger (2) onto the drilling
spindle so that the holes (3) line up.
N Push the retaining pin into the hole.
N Spring clip on the retaining pin must
fit snugly around the auger's shank.
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0000-GXX-1860-A0
A
2
1
3
0000-GXX-0477-A0
0000-GXX-0478-A0
Starting / Stopping the
Engine
Engaging the Auger Brake
N Move the activating lever to
position A . Auger brake is engaged
and auger is blocked.
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 stop switch is normally in the Run
position, i.e. when it is not depressed:
The ignition is switched on – the engine
is ready to start. Operate the stop switch
to switch off the ignition. The ignition is
switched on again automatically after
the engine stops.
Starting the Engine
N Press the manual fuel pump
bulb (9) at least five times – even if
the bulb is already filled with fuel.
N Press home the choke knob (8) and
turn it to the required position – it
must engage
g if the engine is cold
< for warm start – also use this posi
tion if the engine has been running
but is still cold.
Cranking
N Place the unit on the ground:
N Check that the auger brake is
engaged.
N Make sure you have a safe and
secure footing.
N Put your left foot on the handle
frame.
N Left hand on the handle frame – do
not touch the throttle trigger or
lockout lever – your thumb should
be under the fan housing.
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0000-GXX-1862-A0
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0000-GXX-1558-A0
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 Depress throttle trigger lockout and
immediately blip the throttle trigger –
the choke knob moves to the run F
position.
NOTICE
Since the auger brake is still engaged,
the engine must be returned to idling
speed immediately – or the clutch might
otherwise be damaged.
B
N Stand the machine on the tip of the
auger.
N Disengage the auger brake by
moving the activating lever to
position B. Your earth auger is now
ready for operation.
WARNING
Make sure the carburetor is correctly
adjusted. The auger must not rotate
when the engine is idling.
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
0000-GXX-1861-A0
and refuel if necessary.
N Check that the spark plug boot is
properly connected.
N Repeat the starting procedure.
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, depress the manual
fuel pump bulb at least 5 times –
even if the bulb is already filled with
fuel.
N Set the choke knob to suit the
engine temperature.
N Now start the engine.
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Operating Instructions Releasing a Trapped Auger
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.
Working with shaft extension (special
accessory)
Do not fit the shaft extension until the full
length of the auger is in the hole.
WARNING
Starting a hole with the shaft extension
fitted increases the risk of personal
injury because the unit is then at chest
height and cannot be controlled
properly. For the same reason the shaft
extension must be removed before the
full length of the auger is pulled out of
the hole.
If the auger jams in the drill hole
N Shut off the engine immediately.
N Depress the momentary contact
stop switch – the engine stops –
release the stop switch – it springs
back to the run position.
A
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 helps protect enginemounted components (ignition,
carburetor) from thermal overload.
After Finishing Work
Storing for a short period: Wait for the
engine to cool down. To avoid
condensation, fill 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-of-service periods
– see "Storing the Machine".
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0000-GXX-1860-A0
N Engage the auger brake by moving
the activating lever to position A.
N Rotate the whole machine
counterclockwise to unwind the
auger from the ground.
N After releasing the trapped auger,
check operation of the auger brake
– see “Auger Brake”.
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0000-GXX-0482-A0
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3
4
Replacing the Air Filter
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 Remove padding from the handle
frame.
N Turn the choke knob to g.
N Take out 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.
N Replace any damaged parts.
Installing the Filter Element
N Install the filter element in the filter
housing and fit the cover.
N Fit the screws and tighten them
down firmly.
N Fit the padding – see "Assembling
the Unit".
Engine Management
Exhaust emissions are controlled by the
design of the engine and components
(e.g. carburation, ignition, timing and
valve or port timing).
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0000-GXX-0486-A0
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5
Adjusting the Carburetor
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 auger must not
rotate.
Auger rotates when engine is idling
N Turn the idle speed screw (LA)
slowly counterclockwise until the
auger stops rotating 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.
Spark Plug
N If the engine is down on power,
difficult to start or runs poorly at idle
speed, first check the spark plug.
N Fit a new spark plug after about 100
operating hours – or sooner if the
electrodes are badly eroded. Install
only suppressed spark plugs of the
type approved by STIHL – see
"Specifications".
Removing the Spark Plug
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0000-GXX 0537-A0
N Remove the cover (1).
N Pull off the spark plug boot (2).
N Unscrew the spark plug (3).
WARNING
If the auger continues to rotate when the
engine is idling, have your machine
checked and repaired by your servicing
dealer.
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