STIHL BT 120 Owner's Manual

STIHL BT 120 C

STIH)

Instruction Manual
Manual de instrucciones

Warning!

For safe operation follow all safety
precautions in Instruction Manual - improper
use can cause serious injury.

Advertencia!

Para su seguridad durante el manejo de este
producto, siga siempre las precauciones de
seguridad dadas en el manual de
instrucciones - el uso indebido puede causar
lesiones graves.

Contents

English / USA

Guide to Using this Manual .............. 2
Safety Precautions and

Working Techniques ......................... 3

Assembling the Machine ................ 10

Adjusting the Throttle Cable* .......... 11

Fuel ................................................ 11

Fueling ............................................ 12

Auger Brake ................................... 13

Fitting the Auger ............................. 14

Printing inks contain vegetable oils;

paper can be recycled.

Starting / Stopping the Engine ........ 14

Operating Instructions .................... 17

Releasing a Trapped Auger ............ 18

Cleaning the Air Filter ..................... 18

Motor Management ........................ 19

Adjusting the Carburetor ................ 19

Checking the Spark Plug ................ 21

Engine Running Behavior ............... 22

Lubricating the Gearbox ................. 23
Replacing Starter Rope

and Rewind Spring ......................... 23

Storing the Machine ........................ 25

Maintenance Chart ......................... 26

Parts and Controls .......................... 27

Specifications ................................. 28

Printed on chlorine-free paper.© ANDREAS STIHL AG & Co. KG, 2003

Maintenance and Repairs ............... 30
STIHL Incorporated Federal and
California Emission Control

Warranty Statement ........................ 31

Allow only persons who understand this
manual to operate your earth auger.

To receive maximum performance and
satisfaction from your STIHL earth
auger, it is important that you read and
understand
precautions
using your earth auger.

Contact your STIHL dealer or the STIHL
distributor for your area if you do not
understand any of the instructions in this
manual.

the maintenance and safety

, starting on page 3, before

!Warning!

Because an earth auger is a high­torque, gasoline-powered 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.

* see "Guide to Using this Manual"

STIHl

0458 427 3021. M1. L3. T. Printed in Germany

1BT 120 C

English / USA

Guide to Using this Manual

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:

: Step or procedure without direct

reference to an illustration.

Description of step or procedure that
refers directly to the illustration and
contains 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.

Warning where there is a risk of
damaging the machine or individual
components.

Note or hint which is not essential
for using the machine, but may
improve the operator’s under­standing 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 refers to
several models with different
features. Components that are not
installed in all models and related
applications are marked thus
Such components are 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, we cannot be responsible for
changes, modifications or
improvements not covered in this
manual.

2

BT 120 C

Safety Precautions and Working Techniques

English / USA

Warning!

Because an earth auger is
a high-torque, gasoline­powered tool, some
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 and

understand the owner's
manual and the safety instructions.
Careless or improper use of any earth
auger may cause serious or fatal injury.

!Warning!

Do not lend or rent your earth auger
without the owner's manual. Be sure that
anyone using your earth auger
understands the information contained
in this manual.

Have your STIHL dealer show you how
to operate your earth auger. Observe all
applicable local safety regulations,
standards and ordinances.

Danger!

Drilling into or contact with
electrical wires may
cause severe shock,
burns or death. See
"Working Conditions"
below.

!Warning!

Striking a hard object in the earth with
the turning auger and the resulting
slowing or stopping of the auger creates
reactive forces. The transfer of rotational
(reactive) forces can cause the auger
powerhead and handles to rotate
suddenly in a counterclockwise direction
and can result in loss of control or cause
the handle frame to hit the operator or
throw him to the ground, resulting in
serious injury.

!Warning!

Minors should never be allowed to use
an earth auger. Bystanders, especially
children, and animals should not be
allowed in the area where an earth
auger is in use. Never let the earth auger
run unattended.

See the appropriate section of your
owner's manual for a description of the
controls and function of the parts of your
earth auger.

Most of these safety precautions and
warnings apply to the use of all STIHL
earth augers. Different models may
have different parts and controls. See
the appropriate section of your owner's
manual for a description of the controls
and function of the parts of your model
earth auger.

Safe use of an earth auger involves

1. the operator

2. the earth auger

3. the use of the earth auger.

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 an
earth auger when you are fatigued. Be
alert - if you get tired while operating
your earth auger, take a break.
Tiredness may result in loss of control.

3BT 120 C

English / USA

Working with any earth auger can be
strenuous. If you have any condition that
might be aggravated by strenuous work,
check with your doctor before operating
an earth auger.

!Warning!

Prolonged use of earth augers (or other
machines) exposing the operator to
vibrations may produce whitefinger
disease (Raynaud 's phenomenon) or
carpal tunnel syndrome. 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 the 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:

– Wear gloves and keep your hands

warm.

– 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 monitor closely the
condition of their hands and fingers. If
any of the above symptoms appear,
seek medical advice immediately.

!Warning!

The ignition system of your 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.

Clothing must be sturdy
and snug-fitting, but allow
complete freedom of
movement. Avoid loose­fitting jackets, flared or

cuffed pants or anything
that could be drawn into the boring tool.
Wear overalls or long pants to protect
your legs. Secure hair so it is above
shoulder level. Do not wear shorts. Use
gloves when handling the earth auger.

To reduce the risk of

falling as a result of the

forces created by the

earth auger, good footing

is most important. Wear

sturdy footwear with
nonslip soles. Steel-toed safety boots
are recommended.

4

BT 120 C

English / USA

!Warning!

Thrown objects may ricochet and strike
the operator.

Therefore, to reduce the
risk of injury to your eyes
never operate an earth
auger 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).

!Warning!

Wear an approved safety

hard hat to protect your

head when there is a

danger of head injuries.

!Warning!

Earth auger 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.

THE EARTH AUGER

For illustrations and definitions of the
earth auger parts see the chapters on
"Parts and Controls" and "Definitions".

Never modify an earth auger in any way.
Only drilling tools supplied by STIHL or
expressly approved by STIHL for use
with the specific STIHL earth auger
models are authorized. Use of other
drilling tools may increase the risk of
injury.

Other tools, adaptors or fittings may
mount to the auger, but may increase
the risk of injury or death.

THE USE OF THE EARTH AUGER

Transporting the earth auger

!Warning!

Always stop the engine before putting
the earth auger down or carrying it.
Carrying an earth auger with the engine
running is dangerous.

Accidental acceleration of the engine
can cause the drilling tool to rotate.
During operation, the powerhead muffler
and the material around it reach
extremely high temperatures. Avoid
setting down a hot unit onto dry,
flammable material, or touching the hot
muffler, you could receive serious burns.

By hand: Carry the earth auger with the
drilling tool pointing to the rear – with the
hot muffler away from your body.

Transporting by vehicle: When
transporting in a vehicle, properly secure
your power tool to prevent turnover, fuel
spillage and damage.

When the power tool is not in use, shut it
off and put it down so it cannot endanger
others.

!Warning!

Your earth auger
produces toxic exhaust
fumes as soon as the
combustion engine is
running. These gases

(e.g. carbon monoxide)
may be colorless and odorless. To
reduce the risk of serious or fatal injury
from breathing toxic fumes, never run
the earth auger indoors or in poorly
ventilated locations. Ensure proper
ventilation when working in trenches or
other confined areas.

5BT 120 C

English / USA

Fuel Mix

Your STIHL earth auger uses an oil­gasoline mixture for fuel (see the
chapter on "Fuel" in your owner's
manual).

!Warning!

Gasoline is an extremely
flammable fuel. Use
extreme caution when
handling gasoline or fuel
mix. Do not smoke or
bring any fire or flame

near the fuel.

Fueling Instructions

!Warning!

Fuel your earth auger 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 gas tank of a two
cycle engine depending on the fuel
used, the weather conditions, and the
venting system of the tank.

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 earth auger carefully so as
to allow any pressure build-up in the
tank to release slowly. Never remove
fuel filler cap while 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 earth
auger and check for leakage.

!Warning!

Check for fuel leakage while refueling
and during operation. If fuel or oil
leakage is found, do not start or run the
engine until leak is fixed and spilled fuel
has been wiped away. Take care not to
get fuel on your clothing. If this happens,
change your clothing immediately.

!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 with as much force as possible.

Operating the earth auger

The earth auger should be operated by
one person.

To reduce the risk of injury from reactive
forces, the operator must have a firm
grip on the machine and a good foothold
before the throttle is opened to start the
earth auger.

Preparation for the use of the earth
auger

You should always inspect your earth
auger for proper condition and operation
before starting it. Pay special attention to
the throttle trigger, throttle trigger
interlock, stop switch, drilling tool and
auger brake.

6

BT 120 C

English / USA

!Warning!

To reduce the risk of injury from a turning
drilling tool or from reactive forces, the
throttle trigger must move freely and
return immediately to the idle position
when it is released. Regular
maintenance is important in this respect.
Check the condition and the tightness of
the drilling tool.

Auger Brake

Your model earth auger is equipped with
an auger brake, which is designed to
reduce the risk of injury from reactive
forces by stopping the rotation of the
auger / powerhead when the brake
activating lever is engaged. It should
also be used during starting and when
unwinding a trapped auger. See the
chapter on "Auger brake" for information
on engagement of the brake.

!Warning!

Never operate your earth auger if it is
damaged, improperly adjusted or not
completely and securely assembled.
Injury could result.

Starting

For specific starting instructions, see the
appropriate section of your manual.

!Warning!

Your earth auger should be started only
when it is held steady by the operator.

When starting your earth auger, place it
on firm clean ground or other solid
surface in an open area. Maintain good
balance and secure footing.

!Warning!

To reduce the risk of loss of control, be
sure that the earth auger brake is
engaged before starting. Because the
engine speed at starting throttle is fast
enough for the clutch to drive the drilling
tool, the tool will turn unless the auger
brake is engaged.

427BA001 KN

!Warning!

When you pull the starter grip, don't
wrap the starter rope around your
hands. Do not allow the grip to snap
back, but guide the starter rope slowly to
permit the rope to rewind properly.
Failure to follow this procedure may
result in injury to hand or fingers and
may damage the starter mechanism.

Important Adjustments

!Warning!

At correct idle speed, the drilling tool
should not rotate. For directions to
adjust idle speed, see the appropriate
section of your owner's manual. To
reduce the risk of injury from a turning
drilling tool do not use an earth auger
with incorrect idle speed adjustment.

7BT 120 C

English / USA

If you cannot set the correct idle speed,
have your STIHL dealer check your
earth auger and make proper
adjustments or repairs.

Working Conditions

Striking something hard in
the earth, such as a rock
or gravel, may cause the
drilling tool to slow down
suddenly or stop. In such

a situation, some or all of
the rotational force (reactive force) is
transferred to the powerhead and
handle frame of the earth auger which
can cause the auger powerhead and
handles to rotate suddenly in a
counterclockwise direction.

!Warning!

Work carefully in rocky ground or where
other solid objects may be present.
Keep throttle feed pressure to a

427BA002 KN

minimum. If you feel or hear the drilling
tool strike a solid object, release the
throttle trigger immediately and remove
the object before drilling is continued.
When drilling in heavy clay soil, bore
about 1/3 way and remove the auger
from the hole. Clean off auger then
continue in slow steps frequently
clearing drill.

!Warning!

You should hold your earth auger firmly
to control sudden jolts and reactive
forces. Be prepared to release the
throttle completely if the forces become
too great. If reactive forces are not
controlled, rotation of the handles may
result in severe jerking and loss of
control and may cause the handle frame
to strike you or throw you to the ground.
Your model earth auger is equipped with
an auger brake. If the auger hits
something it cannot drill through and the
powerhead begins to rotate so that the
auger brake activating lever strikes the
operator´s thigh and engages, the brake
is designed to stop the rotation of the
powerhead.

!Warning!

In order to reduce the risk of serious or
fatal injury from reactive forces, never
operate your earth auger without a
properly functioning auger brake.

If the auger becomes trapped in the
drillhole, turn off the engine immediately
and remove as descripted in the chapter
entitled "Removing a Trapped Auger".

8

BT 120 C

English / USA

!Warning!

Operate and start your earth auger only
outdoors in a well ventilated area.
Operate the earth auger under good
visibility and daylight conditions only.
Work carefully. Always hold the earth
auger firmly with both hands. Wrap your
fingers tightly around the handles,
keeping the handles cradled between
your thumb and fingers. Keep your
hands in this position to have your earth
auger under control at all times. Make
sure your earth auger handles and grip
are in good condition and free of
moisture, pitch, oil or grease.

DANGER!

Contact with electrical
cables or wires can cause
serious injury or death as
a result of electrical
shock. This unit is not
insulated.

!Warning!

To reduce the risk of electrocution and
damage to property, always be alert for
underground pipes and cables and for
overhead wires. Before drilling, obtain
the necessary plans and permits.
Contact your local utility company or
your locator service, such as "Miss
Utility" or "One Call", for information as
to cable and pipe locations. Where
necessary, confirm actual location by
use of devices such as cable detectors
and/or by carefully dug trenches. Stay
clear of overhead electrical wires when
backing the drilling tool out of the hole. If
any portion of the machine strikes a
wire, it will cause electrical shock or
death.

!Warning!

To reduce the risk of falling, be careful
when carrying or operating the machine
in slippery conditions when the ground is
wet, icy or snow covered. Special care
must also be taken on embankments
and slopes.

Operating Instructions

!Warning!

To reduce the risk of injury, never touch
a rotating drilling tool or drilling spindle
with your hand or any part of your body.
It continues to rotate for a short period
after the throttle lever is released.
Always shut off the engine before putting
the machine down or transporting it over
a long distance.

When taking the drilling tool out of the
hole, lift the machine vertically so that
the tool comes out straight without
canting. Cover and clearly mark
boreholes, to prevent anyone from
stepping in a hole.

9BT 120 C

English / USA

Assembling the Machine

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 claim
warranty for a component which has
not been serviced or maintained
properly or if nonapproved
replacement parts were used, STIHL
may deny warranty.

Use only STIHL replacement parts for
maintenance and repair. Use of parts
manufactured by others may damage
your earth auger or cause serious injury.
Follow the maintenance and repair
instructions in the appropriate section of
your owner's manual.

!Warning!

Always stop the engine before doing any
maintenance or repair work.
Do not attempt any maintenance or
repair work not described in your
owner's manual. Have such work
performed at your STIHL servicing
dealer only.

!Warning!

Check condition of drilling tool at regular
short intervals. If behavior of tool
changes, check immediately for
tightness or any signs of cracks in
particular.

!Warning!

Replace damaged drilling tools
immediately, even if they have only
superficial cracks. Never attempt to
repair damaged drilling tools.

Check fuel filler cap for leaks at regular
intervals. Use the specified spark plug
and make sure it and the ignition lead
are always in good condition. Keep
spark plug and wire connections tight
and clean.

!Warning!

A worn or damaged muffler is a fire
hazard and may cause hearing loss.
Check to see that the muffler is in good
condition. The earth auger must not be
operated if the muffler is not functioning
properly or has been removed. Never
touch a hot muffler or burn will result. In
order to reduce the risk of fire, do not
modify or remove any part of the muffler.
Tighten all nuts, bolts and screws except
the carburetor adjustment screws after
each use.

For any maintenance please refer to the
maintenance chart and to the warranty
statement near the end of this manual.

Store earth auger in a high or locked
place, away from children, and empty
the fuel tank before storing for longer
than a few days.

3

2

1

3

Mounting activating lever for
auger brake

: Place the activating lever (1) in the

clamp.

: Position the clamp (2) on the

activating lever.

: Insert mounting screws (3) and

tighten them down firmly.

Throttle cable adjustment*

On control handles with slide*:

: Go to chapter on "Adjusting the

Throttle Cable".

424BA005

10

* see "Guide to Using this Manual"

BT 120 C

English / USA

Adjusting the Throttle Cable*

A properly adjusted throttle cable is
the precondition for correct
operation in the full throttle, starting
throttle and idle positions.

Adjust the throttle cable only after
the unit is fully assembled.

: Use a suitable tool to push the slide

to the bottom of the slot (see
illustration).

1

2

: Press down the trigger interlock (1)

and squeeze the throttle trigger (2)
(full throttle) – this sets the throttle
cable correctly.

002BA163 KN

Fuel

This engine is certified to operate on
unleaded gasoline and the STIHL two­stroke engine oil at a mix ratio of 50:1.

Your two-stroke engine requires a
mixture of high-quality gasoline and
quality two-stroke air cooled engine oil.

Use mid-grade unleaded gasoline with a

002BA161 KN

minimum octane rating of 89 (R+M/2). If
the octane rating of the mid-grade
gasoline in your area is lower, use
premium unleaded fuel.

Fuel with a lower octane rating 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 even
damage the engine. For this reason
STIHL recommends that you use only
nationally recognized high-quality
unleaded gasoline!

* see "Guide to Using this Manual"

11BT 120 C

English / USA

Fueling

Use only STIHL two-stroke engine oil or
equivalent high-quality two-stroke
engine oils that are designed for use
only in air cooled two-cycle engines.

We recommend STIHL 50:1 two-stroke
engine oil since it is specially formulated
for use in STlHL engines.

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,
chainsaws, mopeds, etc.).

Take care when handling gasoline.
Avoid direct contact with the skin and
avoid inhaling fuel vapor. When filling at
the pump, first remove the canister from
your vehicle and place the canister on
the ground before filling. Do not fill fuel
canisters that are sitting in or on a
vehicle.

The canister should be kept tightly
closed in order to avoid any moisture
getting into the mixture.

The machine‘s fuel tank and the canister
in which fuel mix is stored should be
cleaned as necessary.

Fuel mix ages

Only mix sufficient fuel for a few days
work, not to exceed 3 months of storage.
Store in approved fuel-canisters only.
When mixing, pour oil into the canister
first, and then add gasoline. Close the
canister and shake it vigorously by hand
to ensure proper mixing of the oil with
the fuel.

Gaso­line

Oil (STIHL 50:1 or
equivalent high-quality oils)

US gal. US fl.oz

12.6
2 1/2 6.4
5 12.8

Dispose of empty mixing-oil canisters
only at authorized disposal locations.

427BA003 KN

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 can before fueling your machine.

In order to reduce the risk of burns
or other personal injury from
escaping gas vapor and fumes,
remove the fuel filler cap carefully
so as to allow any pressure build-up
in the tank to release slowly..

After fueling, tighten down the filler
cap by hand as securely as

possible.

12

BT 120 C

Auger Brake

427BA004 KN

A

427BA005 KN

English / USA

B

427BA006 KN

Change the fuel pickup body every
year.

Before storing your machine for a long
period, drain and clean the fuel tank.
Run the engine until the carburetor is
dry.

Engaging the auger brake

: Move the activating lever to

position A engage the brake

– when starting the engine

– at idle speed

– to unwind a trapped auger

If the auger snags on an obstacle in the
hole (e.g. roots or stones) the earth
auger will rotate counterclockwise - the
activating lever is pressed against the
operator's thigh and thus engages the
auger brake.

Disengaging the auger brake

: Move the activating lever to

position B.

13BT 120 C

English / USA

4

Check operation of auger brake

Before you start work:
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.

The auger brake is subject to normal
wear and tear.
Check that it is operating properly before
you start work. If the auger brake fails,
have it repaired immediately by your
STIHL dealer.

Fitting the Auger

: Shut off the engine. Put the earth

auger on the ground so that the
drilling spindle faces up.

: Engage the auger brake.

: Pull retaining pin (1) out of the

auger's shank.

: Push the auger (2) onto the drilling

spindle so that the holes (3) line up.

: Push retaining pin into the hole.

: Spring clip on retaining pin must fit

snugly around auger's shank.

Starting / Stopping the Engine

A

24BA006

: Observe safety precautions – see

chapter on "Safety Precautions".

Engage auger brake

: Move the activating lever to

position A.

427BA005 KN

14

BT 120 C

English / USA

3

START

2

1

Starting

: Press down the throttle trigger

interlock (1), squeeze the throttle
trigger (2) and hold them in that
position.

: Move the slide control (3) to START

and hold it there.

: Now release the throttle trigger,

slide control and throttle trigger
interlock in that order. This is the

starting throttle position.

5

4

392BA027 KN

: Set the choke knob (4):

To g if engine is cold.
To e if engine is warm.
(also use this setting if the engine
has been running but is still cold)

: Press the fuel pump bulb (5) at least

five times.

427BA007 KN

: Place the machine on the ground so

that it is secure.

: Put your right foot in the handle

frame and press down, left hand on
the handle frame.

: Pull the starter grip slowly with your

right hand until you feel it engage –
and then give it a brisk strong pull.
Do not pull out starter rope to full
length – it might break.

: Do not let the starter grip snap back

– guide it back into the housing so
that the starter rope can rewind
properly.

: Continue cranking until the engine

runs.

427BA008 KN

15BT 120 C

English / USA

3

2

When the engine begins to fire:

: Turn the choke knob to e and

continue cranking.

As soon as the engine runs:

: Blip the throttle trigger (2) –

the slide control (3) moves to the run
position # and the engine settles
down to idle speed.

.

Since the auger brake is still
engaged, the engine must be
returned to idle speed immediately
– or the clutch might otherwise be
damaged.

START

392BA028 KN

B

: Stand the unit on the tip of the

auger.

: Disengage the auger brake by

moving the activating lever to
position B. Your earth auger is now
ready for operation.

Make sure the carburetor is
correctly adjusted – the auger must
not rotate when the engine is idling.

To shut down the engine:

: Push the slide control in direction of

c to $

At very low outside temperatures:
Allow engine to warm up

As soon as the engine runs:

: Blip the throttle trigger to disengage

the starting throttle position – the
slide control moves to the normal
run position # and the engine
returns to idle speed.

: Open throttle slightly – warm up the

engine for a short period.

If the engine does not start:

If you did not turn the choke knob to e
quickly enough after the engine began to

427BA006 KN

fire, the combustion chamber has
flooded.

: Turn the choke knob to e

: Set the slide control, trigger

interlock and throttle trigger to the
starting throttle position.

: Start the engine – pull the starter

rope briskly – 10 to 20 pulls may be
necessary.

If the engine still does not start:

: Push the slide control in direction of

c to $

16

BT 120 C

English / USA

Operating Instructions

1

: Pull off the spark plug boot (1).

: Unscrew and dry off the spark plug.

: Open the throttle wide.

: Pull the starter rope several times

to clear the combustion chamber.

: Fit the spark plug and connect the

spark plug boot – press it down
firmly.

: Move the slide control to START.
: Move the choke knob to e even if

the engine is cold.

: Now start the engine.

Throttle cable adjustment

: Check adjustment of throttle cable –

see chapter on "Adjusting the
Throttle Cable".

If tank has been run completely dry
and then refilled:

: Press the fuel pump bulb at least

427BA009 KN

fives times.

: Now start the engine.

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 engine to run for a while
at idle speed so that the heat in the
engine can be dissipated by the flow of
cooling air. This protects engine­mounted components (ignition,
carburetor) from thermal overload.

After Finishing Work

Wait for the engine to cool down. Drain
the fuel Kraftstofftank and store the
machine in a dry place. Check the
tightness of all accessible screws and
nuts (not adjusting screws) at regular
regulars and retighten as necessary.

17BT 120 C

English / USA

Working with Shaft Extension
(special accessory)

Do not fit the shaft extension until the full
length of the auger is in the hole.

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
kept properly under control.

For the same reason the shaft
extension must be removed before
the auger is pulled out of the hole.

Releasing a Trapped Auger

A

If the auger jams in the drill hole - shut off
the engine immediately.

: Move the slide control in direction of

c to $

: Engage the auger brake by moving

the activating lever to position A.

: Now rotate the whole machine to

the left – counterclockwise – to
unwind the auger from the ground.

Cleaning the Air Filter

1

3

2

427BA005 KN

If there is a noticeable loss of
engine power

: Turn choke knob to g

: Press in the tab (1).

: Remove the filter cover (2).

: Clean away loose dirt from inside of

filter cover and around the filter.

: Remove the filter element (3) and

check it – if it is dirty or damaged, fit
a new element.

: Fit the flter element in the filter

cover.

: Push the filter cover into position.

250BA022 KN

18

BT 120 C

Motor Management Adjusting the Carburetor

Carburetor with LD Screw

English / USA

Exhaust emissions are controlled by the
design of the fundamental engine
parameters and components (e.g.
carburation, ignition, timing and valve or
port timing) without the addition of any
major hardware.

General Information

Your carburetor comes from the factory
with a standard setting.

This setting provides an optimum fuel-air
mixture under most operating
conditions.

Standard Setting

: Shut down the engine.

: Remove the auger from the

machine.

: Check air filter and clean or replace

as necessary.

: Check that the throttle cable is

properly adjusted and readjust if
necessary – see chapter on
"Adjusting the Throttle Cable".

+

LD

-

: Carefully screw the idle speed

screw (LD) down onto its seat
counterclockwise (left-hand thread).
Then open it two turns clockwise.

Adjusting Idle Speed

: Carry out standard setting.

: Start and warm up the engine.

250BA021 KN

19BT 120 C