Instruction Manual
Page 2
....fm Contents 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 Auger Brake 14 Fitting the Auger 15 Starting / Stopping ...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 Federal Emission Control Warranty Statement 31 STIHl BT 121...
....fm Contents 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 Auger Brake 14 Fitting the Auger 15 Starting / Stopping ...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 Federal Emission Control Warranty Statement 31 STIHl BT 121...
Instruction Manual
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It continues to rotate for longer than a few days. 10 BT 121 Maintenance, Repair and Storing Maintenance, replacement, or repair of drilling tool at your owner's manual. Use only STIHL replacement parts for leaks at regular intervals. Check condition of the emission control ...devices and systems may cause hearing loss. Check fuel filler cap for maintenance and repair. A worn or damaged muffler is released. Tighten all nuts, bolts and screws except the carburetor adjustment...
It continues to rotate for longer than a few days. 10 BT 121 Maintenance, Repair and Storing Maintenance, replacement, or repair of drilling tool at your owner's manual. Use only STIHL replacement parts for leaks at regular intervals. Check condition of the emission control ...devices and systems may cause hearing loss. Check fuel filler cap for maintenance and repair. A worn or damaged muffler is released. Tighten all nuts, bolts and screws except the carburetor adjustment...
Instruction Manual
Page 18
...now ready for a short period. Your earth auger is cold. : Now start the engine. 427BA009 KN BT 121 17 To shut down firmly. : Move the slide control to START. : Move the choke knob to the...the auger brake by moving the activating lever to idle speed. : Open throttle slightly - Make sure the carburetor is idling. warm up As soon as the engine runs: : Blip the throttle trigger to disengage the ... returns to position B. the auger must not rotate when the engine is correctly adjusted - pull the starter rope briskly - 10 to clear the combustion chamber. : Fit the spark plug and ...
...now ready for a short period. Your earth auger is cold. : Now start the engine. 427BA009 KN BT 121 17 To shut down firmly. : Move the slide control to START. : Move the choke knob to the...the auger brake by moving the activating lever to idle speed. : Open throttle slightly - Make sure the carburetor is idling. warm up As soon as the engine runs: : Blip the throttle trigger to disengage the ... returns to position B. the auger must not rotate when the engine is correctly adjusted - pull the starter rope briskly - 10 to clear the combustion chamber. : Fit the spark plug and ...
Instruction Manual
Page 19
...have to 15 tank fillings. Drain the fuel Kraftstofftank and store the machine in period. English / USA Operating Instructions Throttle cable adjustment : Check adjustment of cooling air. If tank has been run completely dry and then refilled: : Press the fuel pump bulb at regular ...with the shaft extension fitted increases the risk of the hole. 18 BT 121 For the same reason the shaft extension must be removed before the auger is in the hole. This protects enginemounted components (ignition, carburetor) from thermal overload. Starting a hole with Shaft Extension (special accessory...
...have to 15 tank fillings. Drain the fuel Kraftstofftank and store the machine in period. English / USA Operating Instructions Throttle cable adjustment : Check adjustment of cooling air. If tank has been run completely dry and then refilled: : Press the fuel pump bulb at regular ...with the shaft extension fitted increases the risk of the hole. 18 BT 121 For the same reason the shaft extension must be removed before the auger is in the hole. This protects enginemounted components (ignition, carburetor) from thermal overload. Starting a hole with Shaft Extension (special accessory...
Instruction Manual
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... the engine. : Remove the auger from the machine. : Check air filter and clean or replace as stop - the drilling spindle must not rotate. English / USA Adjusting the Carburetor General Information Your carburetor comes from that position. 20 BT 121 Standard Setting : Shut down onto its seat clockwise.
... the engine. : Remove the auger from the machine. : Check air filter and clean or replace as stop - the drilling spindle must not rotate. English / USA Adjusting the Carburetor General Information Your carburetor comes from that position. 20 BT 121 Standard Setting : Shut down onto its seat clockwise.
Instruction Manual
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...spark plug boot (2) snugly onto terminal (1) of the proper size. (Note: If terminal has detachable SAE adapter nut, it down firmly. 22 BT 121 Check grease level after about every 50 hours of operation: : Unscrew the filler plug (1). If no grease can be seen on the inside ...burn injury, use only spark plugs authorized by an authorized STIHL dealer. English / USA Engine Running Behavior Lubricating the Gearbox 2 1 If engine running behavior is unsatisfactory even though the air filter is clean and the carburetor properly adjusted, the cause may be in the boot may create arcing...
...spark plug boot (2) snugly onto terminal (1) of the proper size. (Note: If terminal has detachable SAE adapter nut, it down firmly. 22 BT 121 Check grease level after about every 50 hours of operation: : Unscrew the filler plug (1). If no grease can be seen on the inside ...burn injury, use only spark plugs authorized by an authorized STIHL dealer. English / USA Engine Running Behavior Lubricating the Gearbox 2 1 If engine running behavior is unsatisfactory even though the air filter is clean and the carburetor properly adjusted, the cause may be in the boot may create arcing...
Instruction Manual
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... by dealer 1) Gearbox Re-lubricate Drilling spindle Clean X Auger Inspect X Replace Safety labels Replace 1) STIHL recommends the STIHL servicing dealer X X X X X X X X X X X X X X X x 26 BT 121 drilling spindle must not rotate X Readjust idle Spark plug Readjust electrode gap Replace after each refueling stop ... daily after 100 hours of operation Spark arresting screen in muffler Have checked by STIHL dealer All accessible screws and nuts (not adjusting screws) Retighten Antivibration elements Check X Have replaced by dealer 1) Control handle Check...
... by dealer 1) Gearbox Re-lubricate Drilling spindle Clean X Auger Inspect X Replace Safety labels Replace 1) STIHL recommends the STIHL servicing dealer X X X X X X X X X X X X X X X x 26 BT 121 drilling spindle must not rotate X Readjust idle Spark plug Readjust electrode gap Replace after each refueling stop ... daily after 100 hours of operation Spark arresting screen in muffler Have checked by STIHL dealer All accessible screws and nuts (not adjusting screws) Retighten Antivibration elements Check X Have replaced by dealer 1) Control handle Check...
Instruction Manual
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Main Parts and Controls BT 121 English / USA 1 Starter grip 2 Carburetor adjusting screws 3 Air filter cover 4 Fuel tank filler cap 5 Muffler (with spark arresting screen) 6 Slide control 7 Throttle trigger interlock 8 Throttle trigger 9 Spark plug boot 10 Screw plug 11 Drilling spindle 12 Fuel pump 13 Choke knob 14 Auger brake lever 15 Padding 27
Main Parts and Controls BT 121 English / USA 1 Starter grip 2 Carburetor adjusting screws 3 Air filter cover 4 Fuel tank filler cap 5 Muffler (with spark arresting screen) 6 Slide control 7 Throttle trigger interlock 8 Throttle trigger 9 Spark plug boot 10 Screw plug 11 Drilling spindle 12 Fuel pump 13 Choke knob 14 Auger brake lever 15 Padding 27
Instruction Manual
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...the terms: Extended = 300 hours, Intermediate = 125 hours, Moderate = 50 hours Engine STIHL single cylinder two-stroke engine Displacement: Bore: Stroke: Engine power to the ignition lead. 10. Carburetor Adjusting Screws For tuning the carburetor. 3. Fuel Filler Cap For closing the fuel tank. 5. Throttle Trigger Interlock Must be....in (30.8 cm3) 1.38 in (35 mm) 1.26 in (32 mm) 1.8 bhp (1.3 KW) 12,300 rpm 2,800 rpm 28 BT 121 Spark Plug Boot Connects the spark plug to ISO 8893 Max. Slide Control For starting , switches the engine's ignition off to meet Federal emission requirements...
...the terms: Extended = 300 hours, Intermediate = 125 hours, Moderate = 50 hours Engine STIHL single cylinder two-stroke engine Displacement: Bore: Stroke: Engine power to the ignition lead. 10. Carburetor Adjusting Screws For tuning the carburetor. 3. Fuel Filler Cap For closing the fuel tank. 5. Throttle Trigger Interlock Must be....in (30.8 cm3) 1.38 in (35 mm) 1.26 in (32 mm) 1.8 bhp (1.3 KW) 12,300 rpm 2,800 rpm 28 BT 121 Spark Plug Boot Connects the spark plug to ISO 8893 Max. Slide Control For starting , switches the engine's ignition off to meet Federal emission requirements...
Instruction Manual
Page 33
...The maintenance instructions in writing by STIHL Incorporated, and : replacement of the following list specifically defines the emission-related warranted parts: Carburetor Choke (Cold start enrichment system)...other services and adjustments necessary for regular inspection to STIHL Incorporated specifications that a warranted part is defective. Diagnosis You, as non-defective, STIHL Incorporated will be...to the owner. Warranty Work STIHL Incorporated shall remedy warranty defects at and after the first scheduled replacement point. 32 BT 121 English / USA If any ...
...The maintenance instructions in writing by STIHL Incorporated, and : replacement of the following list specifically defines the emission-related warranted parts: Carburetor Choke (Cold start enrichment system)...other services and adjustments necessary for regular inspection to STIHL Incorporated specifications that a warranted part is defective. Diagnosis You, as non-defective, STIHL Incorporated will be...to the owner. Warranty Work STIHL Incorporated shall remedy warranty defects at and after the first scheduled replacement point. 32 BT 121 English / USA If any ...