STIHL BT 121 Owner's Manual

STIHL BT 121
STIH)
Instruction Manual Manual de instrucciones
Warning!
Read and follow all safety precautions in Instruction Manual – improper use can cause serious or fatal injury.
Advertencia!
Lea y siga todas las precauciones de seguridad dadas en el manual de instrucciones – el uso incorrecto puede causar lesiones graves o mortales.

Contents

English / USA
Guide to Using this Manual .............. 2
Safety Precautions and
Working Techniques ......................... 3
Assembling the Machine ................ 11
Adjusting the Throttle Cable ........... 11
Fuel ................................................ 12
Fueling ............................................ 13
BA_SE_175_008_01_03.fmPrinted on chlorine-free paper.
Auger Brake ................................... 14
Fitting the Auger ............................. 15
Starting / Stopping the Engine ........ 15
Operating Instructions .................... 18
Releasing a Trapped Auger ............ 19
Cleaning the Air Filter ..................... 19
Motor Management ........................ 19
Adjusting the Carburetor ................ 20
Checking the Spark Plug ................ 21
Engine Running Behavior ............... 22
Lubricating the Gearbox ................. 22
Replacing Starter Rope
and Rewind Spring ......................... 23
Storing the Machine ........................ 25
Maintenance Chart ......................... 26
Main Parts and Controls ................. 27
Specifications ................................. 28
Maintenance and Repairs ............... 30
STIHL Incorporated
Printing inks contain vegetable oils; paper can be recycled.
Federal 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.
STIHl
© ANDREAS STIHL AG & Co. KG, 2006
0458 428 8621 A. M1. L6. T. Printed in Germany
1BT 121
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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:
: 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 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 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.
2
BT 121

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.
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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.
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!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.
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!Warning!
Use of this product can generate dust and fumes containing chemicals known to cause respiratory disease, cancer, birth defects, or other reproductive harm. If you are unfamiliar with the risks associated with the particular dust or fume at issue, consult your employer, governmental agencies such as OSHA and NIOSH and other sources on hazardous materials. California and some other authorities, for instance, have published lists of substances known to cause cancer, reproductive toxicity, etc.
Control dust and fumes at the source where possible. In this regard use good work practices and follow the recommendations of OSHA/NIOSH and occupational and trade associations. When the inhalation of toxic dust and fumes cannot be eliminated, the operator and any bystanders should always wear a respirator approved by NIOSH/MSHA for the type of dust and / or fumes encountered.
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 any 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 the fuel filler cap while the engine is running.
Select bare ground for fueling and move at least 10 feet (3 m) from the fueling spot before starting the engine. Wipe off any spilled fuel before starting your 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.
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!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 and their proper function.
!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.
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!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.
!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.
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 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.
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!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".
!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.
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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.
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.
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Assembling the Machine Adjusting the Throttle

Cable
Mounting the Auger Brake Lever
: Place the activating lever (1) in the
retainer.
: Fit the clamp (2) on the activating
lever.
: Insert the screws (3) and tighten
them down firmly.
Fitting the Padding
: Attach the holders (2) of the padding
(1) to the slots in the handle frame.
: Swing the padding upwards and
secure it to the handlebar with the hook-and-loop strips (3).
A properly adjusted throttle cable is the precondition for correct operation in the full throttle, starting throttle and idle positions.
002BA163 KN
: Use a suitable tool to push the slide
to the bottom of the slot (see illustration).
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Fuel

1
2
: Press down the trigger interlock (1)
and squeeze the throttle trigger (2) (full throttle) – this sets the throttle cable correctly.
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 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!
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.
12
BT 121
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.
English / USA

Fueling

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.
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.
427BA003 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.
427BA004 KN
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Auger Brake

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.
Engaging the Auger Brake
: Move the activating lever to
position A to 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.
14
Disengaging the Auger Brake
: Move the activating lever to
position B.
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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

24BA006
: Observe safety precautions – see
chapter on "Safety Precautions".
Engaging Auger Brake
: Move the activating lever to
position A.
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.
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5
4
427BA007 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.
16
: 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.
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.
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: 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 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 $
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1
427BA009 KN
: 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.
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Operating Instructions

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
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.
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.
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Releasing a Trapped Auger Cleaning the Air Filter

1
3
2
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.
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.

Motor Management

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.
250BA022 KN
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