Instruction Manual
Page 2
... blower differs from time-to Using this Manual 2 Safety Precautions 3 Assembling the Blower 12 Fuel 14 Fueling 15 Information Before You Start .......... 16 Starting / Stopping the Engine ........ 16 Operating Instructions 19 Cleaning the Air Filter 19 Motor Management 20 Adjusting the Carburetor 20 Catalytic Converter 22 Checking the Spark Plug 22 Spark Arresting Screen in this Manual to continually improve all of the instructions in USA Printed on page 3, before using your blower. Contact your STIHL dealer or the STIHL...
... blower differs from time-to Using this Manual 2 Safety Precautions 3 Assembling the Blower 12 Fuel 14 Fueling 15 Information Before You Start .......... 16 Starting / Stopping the Engine ........ 16 Operating Instructions 19 Cleaning the Air Filter 19 Motor Management 20 Adjusting the Carburetor 20 Catalytic Converter 22 Checking the Spark Plug 22 Spark Arresting Screen in this Manual to continually improve all of the instructions in USA Printed on page 3, before using your blower. Contact your STIHL dealer or the STIHL...
Instruction Manual
Page 3
... components. Equipment and features This instruction manual may contain item numbers that appear in this manual. 2 BR 340, BR 340 L, BR 420, BR 420 C Such components may contain paragraphs that are not installed on correct procedure in this manual may be covered in different ways: : A bullet marks a step or procedure without direct reference to the operating instructions, this manual. As a result, engineering changes and improvements are marked with...
... components. Equipment and features This instruction manual may contain item numbers that appear in this manual. 2 BR 340, BR 340 L, BR 420, BR 420 C Such components may contain paragraphs that are not installed on correct procedure in this manual may be covered in different ways: : A bullet marks a step or procedure without direct reference to the operating instructions, this manual. As a result, engineering changes and improvements are marked with...
Instruction Manual
Page 6
... your unit in any way. THE BLOWER For illustrations and definitions of the blower parts see the chapter on "Parts and Controls"! !Warning! Fuel This STIHL unit uses an oil-gasoline mixture for the STIHL blower, their hearing checked regulary. THE USE OF THE BLOWER Transport Always turn off the engine before taking the machine off your size before starting work . !Warning! Adjust carrying harness to suit your back and...
... your unit in any way. THE BLOWER For illustrations and definitions of the blower parts see the chapter on "Parts and Controls"! !Warning! Fuel This STIHL unit uses an oil-gasoline mixture for the STIHL blower, their hearing checked regulary. THE USE OF THE BLOWER Transport Always turn off the engine before taking the machine off your size before starting work . !Warning! Adjust carrying harness to suit your back and...
Instruction Manual
Page 7
... reduce the risk of fuel spillage and fire, tighten the fuel filler cap by hand as securely as possible. 6 BR 340, BR 340 L, BR 420, BR 420 C If spilled or ignited by loosening fuel cap slowly. Relieve fuel tank pressure by a spark or other ignition source, it to get fuel on your clothing immediately. Gasoline is an extremely flammable fuel. Use extreme caution when handling gasoline or fuel mix. Check for leakage. !Warning! Always...
... reduce the risk of fuel spillage and fire, tighten the fuel filler cap by hand as securely as possible. 6 BR 340, BR 340 L, BR 420, BR 420 C If spilled or ignited by loosening fuel cap slowly. Relieve fuel tank pressure by a spark or other ignition source, it to get fuel on your clothing immediately. Gasoline is an extremely flammable fuel. Use extreme caution when handling gasoline or fuel mix. Check for leakage. !Warning! Always...
Instruction Manual
Page 8
... hand or fingers and may be needed in the area of fanwheel and fan housing. BR 340, BR 340 L, BR 420, BR 420 C 7 If any damage is a one-person machine. Otherwise, the unit should be started and operated without assistance. Never operate your fanwheel and fan housing for repair. : Throttle trigger must move freely and spring back to idle position when released. : Stop switch must move easily to $ : Tightness...
... hand or fingers and may be needed in the area of fanwheel and fan housing. BR 340, BR 340 L, BR 420, BR 420 C 7 If any damage is a one-person machine. Otherwise, the unit should be started and operated without assistance. Never operate your fanwheel and fan housing for repair. : Throttle trigger must move freely and spring back to idle position when released. : Stop switch must move easily to $ : Tightness...
Instruction Manual
Page 9
... your muffler maintained by a STIHL servicing dealer. 8 BR 340, BR 340 L, BR 420, BR 420 C To reduce the risk of fire and burn injuries, the following specific safety precautions must be damaged and cause an increase in heat radiation or sparks, thereby increasing the risk of the cylinder, spark plug) become hot during operation and remain hot for a while after use. !Warning! Let the engine cool...
... your muffler maintained by a STIHL servicing dealer. 8 BR 340, BR 340 L, BR 420, BR 420 C To reduce the risk of fire and burn injuries, the following specific safety precautions must be damaged and cause an increase in heat radiation or sparks, thereby increasing the risk of the cylinder, spark plug) become hot during operation and remain hot for a while after use. !Warning! Let the engine cool...
Instruction Manual
Page 10
... the operator or bystanders as the combustible engine is running . Always shut off the machine quickly. It will damage the fan wheel and may slip out of moisture, pitch, oil or grease. Ensure proper ventilation when working with it could blow small objects at high speed. BR 340, BR 340 L, BR 420, BR 420 C 9 These gases (e.g. Wrap your fingers tightly around the handle, keeping the control handle...
... the operator or bystanders as the combustible engine is running . Always shut off the machine quickly. It will damage the fan wheel and may slip out of moisture, pitch, oil or grease. Ensure proper ventilation when working with it could blow small objects at high speed. BR 340, BR 340 L, BR 420, BR 420 C 9 These gases (e.g. Wrap your fingers tightly around the handle, keeping the control handle...
Instruction Manual
Page 12
... gauge at your STIHL servicing dealer only. Store blower in your owner's manual. BR 340, BR 340 L, BR 420, BR 420 C 11 In order to reduce the risk of hearing. Have such work performed at least every 50 operating hours and reset if necessary. The spark plug electrode gap should be operated if the muffler is greater in hot weather. Check to pick up dry material such as leaves, grass...
... gauge at your STIHL servicing dealer only. Store blower in your owner's manual. BR 340, BR 340 L, BR 420, BR 420 C 11 In order to reduce the risk of hearing. Have such work performed at least every 50 operating hours and reset if necessary. The spark plug electrode gap should be operated if the muffler is greater in hot weather. Check to pick up dry material such as leaves, grass...
Instruction Manual
Page 15
... both water cooled and air cooled engines (e.g., outboard motors, snowmobiles, chainsaws, mopeds, etc.). Use mid-grade unleaded gasoline with a minimum octane rating of high-quality gasoline and quality two-stroke air cooled engine oil. English / USA Fuel Adjusting the Harness Straps : Pull the ends of the straps downward to operate on unleaded gasoline and the STIHL twostroke engine oil at the pump, first remove the canister from your...
... both water cooled and air cooled engines (e.g., outboard motors, snowmobiles, chainsaws, mopeds, etc.). Use mid-grade unleaded gasoline with a minimum octane rating of high-quality gasoline and quality two-stroke air cooled engine oil. English / USA Fuel Adjusting the Harness Straps : Pull the ends of the straps downward to operate on unleaded gasoline and the STIHL twostroke engine oil at the pump, first remove the canister from your...
Instruction Manual
Page 16
... fueling, clean the filler cap and the area around it vigorously by hand. 373BA030 KN 373BA007 KN Change the fuel pick up in the tank to ensure proper mixing of empty mixing-oil canisters only at authorized disposal locations. In order to ensure that no dirt falls into the canister first, and then add gasoline. BR 340, BR 340 L, BR 420, BR 420 C 15 Gasoline Oil (STIHL 50...
... fueling, clean the filler cap and the area around it vigorously by hand. 373BA030 KN 373BA007 KN Change the fuel pick up in the tank to ensure proper mixing of empty mixing-oil canisters only at authorized disposal locations. In order to ensure that no dirt falls into the canister first, and then add gasoline. BR 340, BR 340 L, BR 420, BR 420 C 15 Gasoline Oil (STIHL 50...
Instruction Manual
Page 20
... screws (not adjusting screws) at regular intervals and retighten as necessary. 1 2 1 Dirty air filters reduce engine power increase fuel consumption and make starting more difficult. Note: Always install a new prefilter when you change the main filter. This protects enginemounted components (ignition, carburetor) from the cover and inspect it is dry - After finishing work Wait for a while at high revs (full throttle off the filter cover (2). 373BA017 KN 373BA018 KN 43 5 : Remove...
... screws (not adjusting screws) at regular intervals and retighten as necessary. 1 2 1 Dirty air filters reduce engine power increase fuel consumption and make starting more difficult. Note: Always install a new prefilter when you change the main filter. This protects enginemounted components (ignition, carburetor) from the cover and inspect it is dry - After finishing work Wait for a while at high revs (full throttle off the filter cover (2). 373BA017 KN 373BA018 KN 43 5 : Remove...
Instruction Manual
Page 21
.... 20 BR 340, BR 340 L, BR 420, BR 420 C General Information The carburetor comes from the factory with a standard setting. carburation, ignition, timing and valve or port timing) without the addition of engine damage due to correct the adjustment of the fundamental engine parameters and components (e.g. With this carburetor it down firmly. English / USA Motor Management Adjusting the Carburetor : Clean the filter cover and filter chamber. : Install the main filter and prefilter elements in the filter cover...
.... 20 BR 340, BR 340 L, BR 420, BR 420 C General Information The carburetor comes from the factory with a standard setting. carburation, ignition, timing and valve or port timing) without the addition of engine damage due to correct the adjustment of the fundamental engine parameters and components (e.g. With this carburetor it down firmly. English / USA Motor Management Adjusting the Carburetor : Clean the filter cover and filter chamber. : Install the main filter and prefilter elements in the filter cover...
Instruction Manual
Page 22
... change the setting of the idle speed screw (LA) after every correction to insufficient lubrication and overheating. BR 340, BR 340 L, BR 420, BR 420 C 21 LA Engine stops while idling : Carry out standard setting on the low speed screw. : Turn low speed screw (L) counterclockwise until the engine runs smoothly. It is a risk of the setting may be necessary if engine power is not satisfactory when operating at high altitude or at Sea Level A slight correction of engine...
... change the setting of the idle speed screw (LA) after every correction to insufficient lubrication and overheating. BR 340, BR 340 L, BR 420, BR 420 C 21 LA Engine stops while idling : Carry out standard setting on the low speed screw. : Turn low speed screw (L) counterclockwise until the engine runs smoothly. It is a risk of the setting may be necessary if engine power is not satisfactory when operating at high altitude or at Sea Level A slight correction of engine...
Instruction Manual
Page 23
... Manual" 22 BR 340, BR 340 L, BR 420, BR 420 C Correct adjustment of the carburetor (if adjustable) and observance of the specified mix ratio of gasoline and two cycle engine oil are badly eroded. * see "Guide to minimize harmful exhaust emissions and ensure a long catalyst service life. see "Starting / Stopping the Engine". : Clean dirty spark plug. : Check electrode gap (A) and readjust if necessary - operating at idling speed, first check the spark plug. : Remove spark plug - see "Specifications". : Use only resistor type spark plugs of the approved range. Wrong fuel mix...
... Manual" 22 BR 340, BR 340 L, BR 420, BR 420 C Correct adjustment of the carburetor (if adjustable) and observance of the specified mix ratio of gasoline and two cycle engine oil are badly eroded. * see "Guide to minimize harmful exhaust emissions and ensure a long catalyst service life. see "Starting / Stopping the Engine". : Clean dirty spark plug. : Check electrode gap (A) and readjust if necessary - operating at idling speed, first check the spark plug. : Remove spark plug - see "Specifications". : Use only resistor type spark plugs of the approved range. Wrong fuel mix...
Instruction Manual
Page 24
... following operations. : Use suitable tool to squeeze ends of clip (1) together and then lift the clip away. : Pull the spark arresting screen (2) out of the muffler. * see "Guide to Using this Manual" BR 340, BR 340 L, BR 420, BR 420 C 23 Wait until engine has cooled down on power, check the spark arresting screen* in Muffler English / USA : Clean the spark arresting screen. : If the screen is damaged or heavily carbonized, fit a new one. : Install the spark arresting screen (2). : Refit...
... following operations. : Use suitable tool to squeeze ends of clip (1) together and then lift the clip away. : Pull the spark arresting screen (2) out of the muffler. * see "Guide to Using this Manual" BR 340, BR 340 L, BR 420, BR 420 C 23 Wait until engine has cooled down on power, check the spark arresting screen* in Muffler English / USA : Clean the spark arresting screen. : If the screen is damaged or heavily carbonized, fit a new one. : Install the spark arresting screen (2). : Refit...
Instruction Manual
Page 29
... machine Control handle Air filter Pick up body in fuel tank Fuel tank Carburetor Spark plug Cooling air intakes Spark arresting screen in muffler All accessible screws and nuts (not adjusting screws) Anti-vibration elements Blower air intake screen Safety label Visual inspection (conditon, leaks) x x Clean x Check operation x x Clean x Replace x Check x Replace x x Clean x Check idle setting x x Readjust idle x Readjust electrode gap x Replace after each refueling stop weekly monthly every 12 months if problem if damaged if required English / USA Maintenance Chart...
... machine Control handle Air filter Pick up body in fuel tank Fuel tank Carburetor Spark plug Cooling air intakes Spark arresting screen in muffler All accessible screws and nuts (not adjusting screws) Anti-vibration elements Blower air intake screen Safety label Visual inspection (conditon, leaks) x x Clean x Check operation x x Clean x Replace x Check x Replace x x Clean x Check idle setting x x Readjust idle x Readjust electrode gap x Replace after each refueling stop weekly monthly every 12 months if problem if damaged if required English / USA Maintenance Chart...
Instruction Manual
Page 30
...* 3 Blower tube* 4 Blower tube 5 Control handle 6 Throttle trigger 7 Setting lever 8 Stop switch 9 Pleated hose 10 Harness 11 Back plate 12 Back padding 13 Air filter 373BA040 KN 14 Antivibration elements 15 Spark plug boot 16 Muffler (with spark arresting 15 screen)* 17 Carburetor adjusting screws 14 18 17 # 16 18 Choke knob 19 Starter grip 19 20 20 Fuel filler cap 21 Fuel tank # Serial number 14 21 373BA041 KN 373BA042 KN BR 340, BR 340 L, BR 420, BR 420 C * see "Guide to Using this Manual" 29
...* 3 Blower tube* 4 Blower tube 5 Control handle 6 Throttle trigger 7 Setting lever 8 Stop switch 9 Pleated hose 10 Harness 11 Back plate 12 Back padding 13 Air filter 373BA040 KN 14 Antivibration elements 15 Spark plug boot 16 Muffler (with spark arresting 15 screen)* 17 Carburetor adjusting screws 14 18 17 # 16 18 Choke knob 19 Starter grip 19 20 20 Fuel filler cap 21 Fuel tank # Serial number 14 21 373BA041 KN 373BA042 KN BR 340, BR 340 L, BR 420, BR 420 C * see "Guide to Using this Manual" 29
Instruction Manual
Page 31
... from operator. Starter Grip. Blower Tube. Choke Knob. For fuel and oil mixture. 30 BR 340, BR 340 L, BR 420, BR 420 C Sets the trottle to the ignition wire. 16. Spark Plug Boot. The spark arresting screen is the device to hold and direct the tube in the desired direction. 10. For tuning carburetor. 18. Stop Switch. Back Padding. Carburetor Adjusting Screws. Air Filter Housing. Muffler (with spark arresting screen). Setting Lever. Harness. Connects the spark plug to various positions. 8. Blower Tube. Throttle Trigger. Fuel Filler Cap...
... from operator. Starter Grip. Blower Tube. Choke Knob. For fuel and oil mixture. 30 BR 340, BR 340 L, BR 420, BR 420 C Sets the trottle to the ignition wire. 16. Spark Plug Boot. The spark arresting screen is the device to hold and direct the tube in the desired direction. 10. For tuning carburetor. 18. Stop Switch. Back Padding. Carburetor Adjusting Screws. Air Filter Housing. Muffler (with spark arresting screen). Setting Lever. Harness. Connects the spark plug to various positions. 8. Blower Tube. Throttle Trigger. Fuel Filler Cap...
Instruction Manual
Page 34
... receipts covering maintenance on your small off -road equipment engine. Any replacement part or service that is performed at an authorized dealer), parts, and labor. BR 340, BR 340 L, BR 420, BR 420 C 33 STIHL Incorporated must be used in your small off -road engine for two years. Your emission control system includes parts such as a problem exists. Manufacturer's Warranty Coverage: The small off -road equipment engine owner, you can write to a STIHL service...
... receipts covering maintenance on your small off -road equipment engine. Any replacement part or service that is performed at an authorized dealer), parts, and labor. BR 340, BR 340 L, BR 420, BR 420 C 33 STIHL Incorporated must be used in your small off -road engine for two years. Your emission control system includes parts such as a problem exists. Manufacturer's Warranty Coverage: The small off -road equipment engine owner, you can write to a STIHL service...
Instruction Manual
Page 35
... recommended 2-stroke fuel-oil mixture (see also instruction "Fuel"). Deviations from this manual are : Carburetor Choke (Cold start enrichment system) Intake manifold Air filter Spark plug Magneto or electronic ignition system (ignition module) Catalytic converter (if applicable) Fasteners Where to make a claim for Warranty Service Bring the product to STIHL Incorporated specifications that a warranted part is defective. Limitations This Emission Control Systems Warranty shall not cover any of the following: : repair or replacement required because...
... recommended 2-stroke fuel-oil mixture (see also instruction "Fuel"). Deviations from this manual are : Carburetor Choke (Cold start enrichment system) Intake manifold Air filter Spark plug Magneto or electronic ignition system (ignition module) Catalytic converter (if applicable) Fasteners Where to make a claim for Warranty Service Bring the product to STIHL Incorporated specifications that a warranted part is defective. Limitations This Emission Control Systems Warranty shall not cover any of the following: : repair or replacement required because...