Stihl BT 45 User manual

Instruction Manual
STIH)
STIHL BT 45
BA_BT45_01_U_A5.book Seite 0 Mittwoch, 22. Dezember 2004 9:38 09

1BT 45
English
BA_SE_107_002_01_07.fmPrinted on chlorine-free paper.
Printing inks contain vegetable oils; paper can be recycled.
© ANDREAS STIHL AG & Co. KG, 2009 0458 421 0121. M0,5. F9. PM. Printed in USA
STIHl
Contents
Guide to Using this Manual .............. 2
Safety Precautions and
Working Techniques ......................... 3
Mounting the Handles ...................... 9
Using the Power Drill ...................... 10
Fuel ................................................ 12
Fueling ............................................ 13
Gearbox .......................................... 14
Fitting the Drilling Tool .................... 15
Starting / Stopping the Engine ........ 16
Operating Instructions .................... 18
Releasing a Trapped Auger ............ 18
Cleaning the Air Filter ..................... 19
Adjusting the Carburetor ................ 19
Checking the Spark Plug ................ 21
Engine Running Behavior ............... 22
Replacing Starter Rope
and Rewind Spring ......................... 22
Storing the Machine ........................ 24
Maintenance Chart ......................... 25
Minimize Wear and
Avoid Damage ................................ 26
Main Parts and Controls ................. 27
Specifications ................................. 28
Special Accessories ....................... 29
Maintenance and Repairs ............... 29
Certificate of Conformity ................. 29
Quality Certification ........................ 30
Dear Customer,
Thank you for choosing a quality
engineered STIHL product.
This machine has been built using
modern production techniques and
comprehensive quality assurance.
Every effort has been made to ensure
your satisfaction and troublefree use
of the machine.
Please contact your dealer or our
sales company if you have any
queries concerning your machine.
Hans Peter Stihl

2
English
BT 45
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

3BT 45
English
Special safety
precautions must be
observed when working
with this power tool
because of its high
torque, the sharp-edged
drilling tools and the high speed of the
drilling tool in certain applications.
It is important that you
read and understand the
instruction manual before
using your power tool for
the first time. Keep the
manual in a safe place for
future reference. Non-observance of the
following safety precautions may cause
serious or even fatal injury.
Always observe local safety regulations,
standards and ordinances.
If you have never used this power tool
model before:
Have your dealer or other experienced
user show you how to operate your
power tool or attend a special course of
training in power tool operation.
Minors should never be allowed to use a
power tool. Children, bystanders and
animals should not be allowed in the
area where a power tool is in use.
When the machine is not in use (work
break), shut it off so that it does not
endanger others and secure it against
unauthorized use.
The power tool user is responsible for
avoiding injury to third parties or damage
to their property.
Do not lend or rent your machine without
the instruction manual. Be sure that
anyone using your machine is familiar
with this model and its operation and
understands the information contained
in this manual.
To operate the power tool you must be
rested, in good physical condition and
mental health.
If you have any condition that might be
aggravated by strenuous work, check
with your doctor before operating a
power tool.
Persons with pacemakers only: The
ignition system of your machine
produces an electromagnetic field of a
very low intensity. This field may
interfere with some pacemakers. To
reduce health risks, STIHL recommends
that persons with pacemaker consult
their physician and the pacemaker
manufacturer before operating this tool.
Do not operate the power tool if you are
under the influence of any substance
(drugs, alcohol) which might impair
vision, dexterity or judgment.
Depending on the drilling tool and
attachments mounted, use your power
tool only for drilling holes in wood, holes
for plants (shallow holes in loosened
soil) or holes in ice.
Do not use your power tool for any other
purpose since this may result in
accidents or damage to the machine.
Never attempt to modify your power tool
in any way since this can be extremely
dangerous and also result in accidents
or damage to the machine.
Safety Precautions and
Working Techniques

4
English
BT 45
Only mount drilling tools and
accessories that are explicitly approved
for this power tool model by STIHL or
are technically identical. If you have any
questions in this respect, consult a
servicing dealer. To reduce the risk of
accidents or damage to the machine,
use only high quality tools and
accessories.
STIHL recommends the use of STIHL
original tools and accessories. The
characteristics of these components are
specifically designed to match your
machine and meet your performance
requirements.
Clothing and Equipment
Wear proper protective clothing and
equipment.
Clothing must be sturdy
but allow complete
freedom of movement.
Wear snug-fitting clothing,
e.g. an overall and jacket
combination, do not wear
a work coat.
Avoid loose-fitting jackets, scarves,
neckties, jewellery or anything that could
get caught on wood or brush or moving
parts of the machine.
Tie up and confine long
hair (e.g. with a hair net,
cap, hard hat, etc.).
Wear sturdy boots with non-slip soles.
Wear safety glasses or
other suitable eye
protection.
Wear hearing
protection, e.g. earplugs
or ear muffs.
Wear a safety hard hat where there is a
danger of head injuries from falling
objects.
Wear heavy-duty
gloves, preferably made
of leather.
STIHL offers a comprehensive range of
protective clothing and equipment.
Transporting the Machine
Always turn off the engine.
Carry the machine with the drilling tool
pointing down – keep the hot muffler
away from your body.
It is also possible to use a shoulder strap
(special accessory).
Transporting in a vehicle: Properly
secure your machine to prevent
turnover, fuel spillage and damage.

5BT 45
English
Fueling
Gasoline is an
extremely flammable
fuel. Keep clear of naked
flames and fire. Do not
spill any fuel – do not
smoke.
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.
Fuel your power tool in a well-ventilated
area, outdoors only. If you spill fuel, wipe
the machine immediately – if fuel gets on
your clothing, change immediately.
Insert the fuel cap with
hinged grip (bayonet type
cap) correctly in the
opening, turn it clockwise
as far as stop and fold the
grip down.
To avoid risk of serious or fatal burn
injuries, check for leakage. If fuel
leakage is found, do not start or run the
engine until leak is fixed.
Before Starting
Check that your power tool is properly
assembled and in good condition – refer
to appropriate chapters in the instruction
manual:
– Slide control / stop switch must
move easily to STOP or 0
– Additional front assist handle
properly mounted to suit drilling tool
being used.
– Smooth action of throttle trigger and
throttle trigger interlock – throttle
trigger must return automatically to
idle position.
– Check that spark plug boot is secure
– a loose boot may cause arcing
that could ignite combustible fumes
and cause a fire.
– Never attempt to modify any of the
controls or safety devices.
– Handles securely mounted, dry and
clean – free from oil and dirt – for
safe control of the machine.
To reduce risk of accidents and personal
injury, do not operate your machine if it is
damaged or not properly assembled.
Starting the Engine
Start the engine at least 3 meters from
the fueling spot, outdoors only.
Gearbox in neutral – knob in N position.
Place the machine on firm ground in an
open area. Make sure you have good
balance and secure footing. Hold the
machine securely.
Your power tool is a one-person unit. Do
not allow other persons in the general
work area, even when starting.
To reduce the risk of injury, avoid contact
with the drilling tool.
Do not drop start the power tool. The
correct starting procedure is described
in your instruction manual.
Check the idle speed setting. The drilling
tool must not move when the engine is
idling with the throttle trigger released.
To reduce the risk of fire, keep hot
exhaust gases and hot muffler away
from easily combustible materials (e.g.
wood chips, bark, dry grass, fuel).

6
English
BT 45
Holding and Controlling the
Machine
Always hold the unit firmly with both
hands on the handles. Make sure you
always have good balance and secure
footing.
Wrap your fingers and thumbs around
the handles. Right hand on the control
handle, left hand on the assist handle.
Left handers should follow these
instructions too.
Drilling planting holes and ice holes
Drilling holes in wood
During Operation
In the event of imminent danger or in an
emergency, switch off the engine
immediately – move the slide control /
stop switch to 0or STOP.
Do not allow any other persons in the
work area. To reduce the risk of injury,
keep a sufficiently safe distance away
from other persons.
Make sure the idle speed setting is
correct. The drilling tool must not rotate
when the engine is idling with the throttle
trigger released.
Check and correct the idle speed setting
at regular intervals. If the drilling tool still
rotates, have your dealer check your
machine and make proper adjustments
or repairs.
Take special care in slippery conditions
– damp, snow, ice, on slopes, uneven
ground, etc.
Watch out for obstacles: Roots, tree
stumps or holes which could cause you
to trip or stumble.
Make sure you always have firm and
secure footing.
When working at a height that exceeds
the unit’s reach:
– Use a lift bucket
– Never work on a ladder
– Never work in a tree
– Never work on an insecure support
– Never work above shoulder height
– Never operate your unit with one
hand
Be particularly alert and cautious when
wearing hearing protection because
your ability to hear warnings (shouts,
alarms, etc.) is restricted.
To reduce the risk of accidents, take a
break in good time to avoid tiredness or
exhaustion.
Work calmly and carefully – in daylight
conditions and only when visibility is
good – ensure you do not endanger
others – stay alert at all times.

7BT 45
English
Your power tool produces
toxic exhaust fumes as
soon as the engine is
running. These fumes
may be colorless and
odorless. Never run the
engine indoors or in poorly ventilated
locations, even if your model is equipped
with a catalytic converter.
To reduce the risk of serious of fatal
injury from breathing toxic fumes,
ensure proper ventilation when working
in trenches, hollows or other confined
locations.
Operate your power tool so that it
produces a minimum of noise and
emissions – do not run the engine
unnecessarily, accelerate the engine
only for drilling
To reduce risk of fire, do not smoke
while operating or standing near your
power tool. Note that combustible fuel
vapor may escape from the fuel system.
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
is tight (no leaks) and the safety devices
are working properly. Do not continue
operating your power tool if it is
damaged. In case of doubt, have the
machine checked by your servicing
dealer.
Do not operate your power tool with the
starting throttle lock engaged as you do
not have control of the engine speed in
this position.
To reduce the risk of injury, never touch
the drilling tool or drilling spindle unless
the engine is stopped and the gearbox is
in neutral (knob in N position).
To avoid the risk of
electrocution, do not
touch electric power lines.
Before starting drilling work, make sure
there are no buried cables or pipes in the
work area (e.g. gas, water, electricity):
– Obtain the necessary information
from the public utilities.
– In case of doubt, check the
existence of cables and pipes with
detectors or dig inspection holes.
Hold the machine firmly to control
sudden jolts and reactive forces. Keep
feed pressure to a minimum.
Work particularly carefully in rocky
ground or ground with a heavy root
structure.
Cover and clearly mark boreholes.
To reduce the risk of injury, always shut
off the engine, disconnect the spark plug
boot and set the gearbox to neutral
(knob in Nposition) before changing the
drilling tool.
To reduce the risk of serious burn
injuries, avoid touching hot parts of the
machine, especially the surface of the
muffler.
Shut off the engine before leaving the
machine unattended.
Check the condition of the drilling tools
(augers) at regular short intervals.
Replace damaged or blunt drilling tools
immediately.

8
English
BT 45
Vibrations
Prolonged use of the unit 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)
–breaks
The period of usage is shortened by:
– Any personal tendency to suffer
from poor circulation (symptoms:
frequently cold fingers, itching).
– Low outside temperatures.
– Gripping force (a tight grip hinders
circulation).
Continual and regular users should
monitor closely the condition of their
hands and fingers. If any of the above
symptoms appear, seek medical advice.
Maintenance and repairs
The machine must be serviced regularly.
Do not attempt any maintenance or
repair work not described in your
Owner’s Manual. All other work should
be carried out by a servicing dealer.
STIHL recommends that maintenance
and repair work be carried out only by
authorized STIHL dealers. STIHL
dealers receive regular training and are
supplied with technical information.
Use only high-quality replacement parts,
in order to avoid the risk of accidents or
damage to the machine. Contact a
dealer if in doubt.
STIHL recommends the use of genuine
STIHL spare parts. Such parts have
been optimized for the machine and the
user's requirements.
Before starting any maintenance or
repair work and before cleaning the
machine, always stop the engine and
disconnect the spark plug boot to
avoid all risk of injury if the engine
starts up inadvertently. – Exception:
adjustment of carburetor and idle speed.
Do not service or store the machine near
a naked light – risk of fire due to the
fuel.
Check fuel cap regularly for tightness.
Use only the spark plugs approved by
STIHL – see Specifications.
Inspect ignition lead (insulation in good
condition, secure connection).
To reduce the risk of fire due to ignition
outside the cylinder, move the slide
control / stop switch to STOP or 0before
turning the engine over on the starter
with the spark plug boot removed or the
spark plug unscrewed.
Check that the muffler is in perfect
working condition.
Do not use the machine if the muffler is
damaged or missing – risk of fire! –
Hearing damage!
Do not touch the hot muffler – risk of
burns!
The condition of the anti-vibration
buffers influences the machine's
vibrations – they must be examined
regularly.

9BT 45
English
Assist handle for wood drill
Before mounting a new wood drill assist
handle for the first time:
:Hold the handle (1) by the clamp
and turn the grip clockwise until the
gap (2) in the clamp is completely
closed.
This breaks the small plastic retainer in
the clamp and allows the clamp to be
opened up.
Normal mounting procedure
:Hold the clamp firmly and rotate the
grip about 5 full turns counter-
clockwise.
:Open up the clamp slightly.
:Push the handle over the chuck until
it butts against the machine. The
clamp must engage the groove on
the gearbox housing.
:Screw handle into clamp clockwise.
:Move to required position and
tighten the grip firmly.
Assist handle for planting hole
auger and ice auger
:Loose the two wing screws (3) on
the flange (4).
:Make sure the polymer bushing is
correctly seated (see arrow)
Mounting the Handles
421BA003 KN
1
2
421BA036 KN
421BA005 KN
421BA037 KN
3
4
3

10
English
BT 45
:Push the flange onto the machine
as far as stop and line it up.
:Insert the handle tube (5) in the
flange.
:Move the assist handle to the
required position and tighten the
two wing screws firmly.
Your power drill can be used for a range
of applications, e.g. fence-building and
carpentry (kit for wood drill), in
landscaping and gardening (kit for
planting hole auger) and ice fishing (kit
for ice auger).
General
To change the drilling tool, always
shut off the engine and set the rotary
knob to N.
Always fit the assist handle
specified for the drilling tool you
intend to use. See "Mounting the
Handles".
During operation, always hold the
machine firmly with both hands to
control unexpected reactive forces
caused by the drilling tool jamming
in or passing through the material. Working with the ice auger
:Before stepping on the ice, check its
carrying capacity.
:Make sure you have a safe and
secure footing.
During operation, always hold the
machine firmly with both hands to
control unexpected reactive forces
caused by the drilling tool jamming
in or penetrating the ice. Release
the throttle trigger if the drilling tool
jams.
5
421BA007 KN
Using the Power Drill
421BA008 KN

11BT 45
English
Working with the planting hole
auger**
:Make sure you have a secure
footing.
During operation, always hold the
machine firmly with both hands to
control unexpected reactive forces
that may occur if the drilling tool
jams, e.g. in rocky ground. Release
the throttle trigger if the drilling tool
jams.
** see "Special Accessories"
The planting hole auger should be
operated only with the gearbox set
to position 1.
The tool speed is too high for drilling
planting holes when the gearbox is
set to poistion 2.
Working with a wood drill**
or twist drill
:Make sure you have a secure
footing.
During operation, always hold the
machine firmly with both hands to
control unexpected reactive forces
caused by the drilling tool jamming
in or passing through the wood. Be
prepared to release the throttle
trigger.
Drilling tool jammed
See "Releasing a Trapped Auger".
** see "Special Accessories"
421BA002 KN 421BA009 KN

12
English
BT 45
Your engine requires a mixture of
gasoline and engine oil.
For health reasons, avoid direct skin
contact with gasoline and avoid inhaling
gasoline vapor.
STIHL MotoMix
STIHL recommends the use of STIHL
MotoMix. This ready-to-use fuel mix
contains no benzol or lead, has a high
octane rating and ensures that you
always use the right mix ratio.
STIHL MotoMix is specially
formulated for use in STlHL engines
and guarantees a long engine life.
MotoMix is not available in all markets.
Mixing Fuel
Unsuitable fuels or lubricants or mix
ratios other than those specified
may result in serious damage to the
engine. Poor quality gasoline or
engine oil may damage the engine,
sealing rings, hoses and the fuel
tank.
Gasoline
Use only high-quality brand-name
gasoline with a minimum octane rating
of 90 – leaded or unleaded.
If your machine is equipped with a
catalytic converter, you must use
unleaded gasoline.
A few tankfuls of leaded gasoline
will greatly reduce the efficiency of
the catalytic converter.
Engine Oil
Use only quality two-stroke engine oil.
We recommend STIHL two-stroke
engine oil since it is specially
formulated for use in STlHL engines
and guarantees a long engine life.
If STIHL two-stroke engine oil is not
available, use only quality two-stroke oil
designed for use in air cooled engines.
Do not use oils designed for water
cooled engines or engines with a
separate lubricating system (e.g.
conventional four-stroke engines).
Use only STIHL 50:1 two-stroke
engine oil for the fuel mix in models with
a catalytic converter.
Mix Ratio
STIHL 50:1 two-stroke engine oil:
50 parts gasoline to 1 part oil
Other high-quality two-stroke engine
oils:
25 parts gasoline to 1 part oil
Examples
:Use a canister approved for storing
fuel. Pour oil into the canister first,
then add gasoline and mix
thoroughly.
Fuel
Gaso-
line
STIHL
engine oil
50:1
Other high-
quality two-
stroke engine
oils:
25:1
Liters Liters (cc) Liters (cc)
1 0.02 (20) 0.04 (40)
5 0.10 (100) 0.20 (200)
10 0.20 (200) 0.40 (400)
15 0.30 (300) 0.60 (600)
20 0.40 (400) 0.80 (800)
25 0.50 (500) 1.00 (1000)

13BT 45
English
Storing Fuel
Store fuel only in approved safety-type
fuel canisters in a dry, cool and safe
location protected from light and the sun.
Fuel mix ages:
Only mix sufficient fuel for a few weeks
work. Do not store fuel mix for longer
than 3 months.
Exposure to light, the sun, low or high
temperatures can quickly make the fuel
mix unusable.
:Thoroughly shake the mixture in the
canister before fueling your
machine.
Pressure may build up in the
canister – open it carefully.
:Clean the fuel tank and canister
from time to time.
Dispose of remaining fuel and
cleaning fluid properly in
accordance with local regulations
and environment requirements.
:Before fueling, clean the filler cap
and the area around it to ensure that
no dirt falls into the tank.
:Position the machine so that the fuel
filler cap is pointing up.
Avoid spills while refueling and do not fill
the tank to the brim. STIHL recommends
use of the STIHL filling system.
Opening the cap
:Swing the clip outward to upright
position.
:Rotate the cap about 1/4 turn
counterclockwise and remove.
Fueling
421BA011 KN
421BA012 KN421BA013 KN

14
English
BT 45
Closing the cap
:Place the cap in position – clip
upright – the marks must line up
(see arrows).
:Rotate the cap about 1/4 turn
clockwise.
:Fold the clip down so that it is flush
with the top of the cap.
If the clip does not lie completely flat on
the cap, the cap is not properly closed.
You must repeat the above steps.
Change the fuel pickup body
once every year
:Drain the fuel tank.
:Use a hook to pull the fuel pickup
body out of the tank and take it off
the hose.
:Push the new pickup body into the
hose.
:Place the pickup body in the tank.
The power drill is equipped with a
change-speed gearbox. Depending on
the application and the drilling tool used,
the speed can be adjusted to suit
requirements.
Knob positions
The position of the rotary knob may
be changed only when the engine is
running at idle speed – the drilling
spindle must be stationary.
It may be necessary to turn the
drilling spindle slightly before the
rotary knob can be moved to the
required position.
Do not change the position of the
rotary knob while the engine is
running above idle speed – the
drilling tool rotates.
421BA014 KN421BA015 KN
421BA016 KN
Gearbox
421BA017 KN

15BT 45
English
N (Neutral)
– Gearbox idle position for starting the
engine
– For adjusting the carburetor
– For changing drilling tools
1
– Low-speed clockwise rotation, see
"Specifications"
2
– High-speed clockwise rotation, see
"Specifications"
R
– Counterclockwise rotation, e.g. for
releasing a trapped drilling tool
:With the engine stopped (knob in N
position), put the machine on the
ground and make sure it is secure.
Chuck for wood drills** or twist drills
:Insert the drilling tool (1) in the
chuck (2) and tighten it firmly.
!When using the geared rim drill
chuck**, make sure you remove the
chuck key before starting up.
** see "Special Accessories"
Adapters for ice auger1) or
planting hole auger**
:Screw the adapter (3) onto the
drilling spindle (4).
:Use a 13mm open-end wrench to
hold the spindle steady and tighten
the adapter firmly with a 19mm
open-end wrench.
:Secure the drilling tool (5) in the
adapter.
Use a 17mm open-end wrench to
secure and release the planting
hole auger.
1) Depending on market
** see "Special Accessories"
Fitting the Drilling Tool
421BA018 KN
12
5
421BA019 KN
5
4
3
3
3

16
English
BT 45
:Set rotary knob to N(gearbox in
neutral).
The machine may only be started
with the gearbox in neutral.
If left in positions 1, 2and R, the
drilling tool may begin to rotate
when the clutch engagement speed
is reached. This could result in an
accident and personal injury
from loss of control.
Starting
:Press in the choke lever and set
it to (1):
For cold start to l
For warm start to j
(also use this setting if the engine
has been running but is still cold).
:Move the stop switch (2) to #.
:Squeeze the throttle trigger (3) and
hold it there.
:Press in the starting throttle lock (4)
and hold it there.
:Now release the throttle trigger and
the starting throttle lock in that order.
This is the starting throttle
position.
:Press the fuel pump bulb (5) at least
five times.
Starting / Stopping
the Engine
421BA020 KN
4
1
421BA021 KN
2
3
421BA022 KN
5

17BT 45
English
:Place the machine on the ground so
that it is secure.
:Press the machine against the
ground with your left hand on the
engine housing.
: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 vertically into the housing
so that the starter rope can rewind
properly.
When engine begins to fire:
:Move choke lever to j
and continue cranking.
As soon as engine runs:
:Blip the throttle trigger – the starting
throttle lock moves to the normal run
position and the engine returns to
idle speed.
To shut down the engine
:Move the stop switch to $.
At very low temperatures
As soon as the engine runs:
:Blip the throttle trigger to disengage
the starting throttle lock – it moves
to the normal run position and the
engine returns to idle speed.
:Open throttle slightly – warm up
engine for short period.
If the engine does not start:
If you did not move the choke lever to j
quickly enough after the engine began to
fire, the combustion chamber is flooded.
:Set choke lever to j.
:Set throttle trigger to 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:
:Move the stop switch to $– this is
important to prevent any errant
ignition spark.
421BA001 KN
421BA023 KN

18
English
BT 45
:Pull off the spark plug boot (6).
:Unscrew and dry off the spark plug.
:Open the throttle fully.
: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.
:Set the stop switch to #.
:Move the choke lever to the warm
start position jeven if the engine
is cold.
:Now start the engine.
If tank has been run completely
dry and then refilled
:Press the fuel pump bulb at least
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 flow of
cooling air. This protects engine-
mounted components (ignition,
carburetor) from thermal overload.
After finishing work
Storing for short period:
Wait for engine to cool down. To avoid
condensation, fill the fuel tank and keep
the unit in a dry place until you need it
again. Storing for a long period:
see chapter "Storing the Machine".
If the auger/drill jams in the drill
hole:
:Let go of the throttle trigger so that
the engine returns to idle speed.
:Move rotary knob to R position
(counterclockwise rotation) – it may
be necessary to turn the machine a
little until the knob can be moved to
the required position.
:Hold the machine firmly with both
hands on the handles.
:Operate the throttle trigger.
:Increase engine speed and slowly
pull the drilling tool out of the drill
hole.
421BA024 KN
6
Operating Instructions Releasing a Trapped Auger
421BA025 KN

19BT 45
English
If there is a noticeable loss of
engine power
:Move choke lever to l.
:Loosen the nut (1) and remove the
filter cover (2).
:Clean away loose dirt from around
the filter.
:Take the filter (3) out of the filter
housing (4).
:Replace with a new filter – or, as a
temporary measure, knock it out or
blow it clear – do not wash.
:Replace any damaged parts.
:Install the filter in the filter housing.
:Fit the filter cover, engage the two
tabs (arrows) at the bottom first.
:Engage the nut and tighten it down
firmly.
General Information
The carburetor comes from the factory
with a standard setting.
This setting provides an optimum fuel-air
mixture under most operating
conditions.
With this carburetor it is only possible to
adjust the engine idle speed within fine
limits.
Cleaning the Air Filter
421BA026 KN
1
2
34
421BA038 KN
Adjusting the Carburetor
13/4
H
L
LA
421BA027 KN