Instruction Manual
Page 2
... Filter 19 Motor Management 20 Adjusting the Carburetor 20 Catalytic Converter 22 Checking the Spark Plug 22 Spark Arresting Screen in this Manual, please contact your STIHL dealer for your STIHL blower, it is to -time. To receive maximum performance and satisfaction from your... 28 Parts and Controls 29 Specifications 31 Special Accessories 32 Maintenance and Repairs 32 STIHL Incorporated Federal and California Emission Control Warranty Statement 33 Trademarks 35 STIHl BR 340, BR 340 L, BR 420, BR 420 C English / USA Allow only persons who understand this Manual. !Warning!
... Filter 19 Motor Management 20 Adjusting the Carburetor 20 Catalytic Converter 22 Checking the Spark Plug 22 Spark Arresting Screen in this Manual, please contact your STIHL dealer for your STIHL blower, it is to -time. To receive maximum performance and satisfaction from your... 28 Parts and Controls 29 Specifications 31 Special Accessories 32 Maintenance and Repairs 32 STIHL Incorporated Federal and California Emission Control Warranty Statement 33 Trademarks 35 STIHl BR 340, BR 340 L, BR 420, BR 420 C English / USA Allow only persons who understand this Manual. !Warning!
Instruction Manual
Page 8
... !Warning! For specific starting . Maintain good balance and secure footing. !Warning! if boot is loose, sparks may result in the area of the outlet nozzle or exhaust. Stop the operation immediately if you pull the...STIHL dealer for damage (cracks, nicks, chipping). If any damage is found, stop using the unit and contact your machine if it . To reduce the risk of another person may damage the starter mechanism. To reduce the risk of spark plug... appropriate section of fanwheel and fan housing. BR 340, BR 340 L, BR 420, BR 420 C 7 English / USA Before Starting !Warning!
... !Warning! For specific starting . Maintain good balance and secure footing. !Warning! if boot is loose, sparks may result in the area of the outlet nozzle or exhaust. Stop the operation immediately if you pull the...STIHL dealer for damage (cracks, nicks, chipping). If any damage is found, stop using the unit and contact your machine if it . To reduce the risk of another person may damage the starter mechanism. To reduce the risk of spark plug... appropriate section of fanwheel and fan housing. BR 340, BR 340 L, BR 420, BR 420 C 7 English / USA Before Starting !Warning!
Instruction Manual
Page 9
...not continue work with a catalytic converter, which is designed to idle or is still hot. To reduce the risk of the cylinder, spark plug) become hot during operation and remain hot for a while after use. !Warning! Since a muffler with the cooling effect of fire ...your backpack blower down as rapidly as pine needles, branches or leaves. !Warning! Have your muffler serviced and repaired by a STIHL servicing dealer. 8 BR 340, BR 340 L, BR 420, BR 420 C The muffler could be observed. !Warning! Let the engine cool down before refueling your muffler maintained by your muffler...
...not continue work with a catalytic converter, which is designed to idle or is still hot. To reduce the risk of the cylinder, spark plug) become hot during operation and remain hot for a while after use. !Warning! Since a muffler with the cooling effect of fire ...your backpack blower down as rapidly as pine needles, branches or leaves. !Warning! Have your muffler serviced and repaired by a STIHL servicing dealer. 8 BR 340, BR 340 L, BR 420, BR 420 C The muffler could be observed. !Warning! Let the engine cool down before refueling your muffler maintained by your muffler...
Instruction Manual
Page 12
...were used, STIHL may be performed by others may cause loss of personal injury from fire and explosion, never attempt to pick up dry material such as leaves, grass, small twigs and bits of your owner's manual. Use the specified spark plug and make...STIHL servicing dealer only. However if you claim warranty for maintenance and repair. Always stop the engine and make sure it and the ignition lead are badly pitted. Have such work not described in hot weather. Remember that the risk of children. For any nonroad engine repair establishment or individual. BR 340, BR 340 L, BR 420, BR...
...were used, STIHL may be performed by others may cause loss of personal injury from fire and explosion, never attempt to pick up dry material such as leaves, grass, small twigs and bits of your owner's manual. Use the specified spark plug and make...STIHL servicing dealer only. However if you claim warranty for maintenance and repair. Always stop the engine and make sure it and the ignition lead are badly pitted. Have such work not described in hot weather. Remember that the risk of children. For any nonroad engine repair establishment or individual. BR 340, BR 340 L, BR 420, BR...
Instruction Manual
Page 19
... rope several times to the lower stop - warm up As soon as engine runs: : Move the setting lever (2) to clear the combustion chamber. 18 BR 340, BR 340 L, BR 420, BR 420 C 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 is cold. : Now start the engine. To shut down to e even if the engine is flooded. : Pull off the spark plug boot. : Unscrew and dry...
... rope several times to the lower stop - warm up As soon as engine runs: : Move the setting lever (2) to clear the combustion chamber. 18 BR 340, BR 340 L, BR 420, BR 420 C 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 is cold. : Now start the engine. To shut down to e even if the engine is flooded. : Pull off the spark plug boot. : Unscrew and dry...
Instruction Manual
Page 23
.... : Dirty air filter. : Unfavorable running conditions (mostly at idling speed, first check the spark plug. : Remove spark plug - Rectify problems which may only be operated with unleaded gasoline and STIHL two cycle engine oil or equivalent quality two cycle engine oils in a mix ratio of 50:1... condition of the spark plug. see "Guide to minimize harmful exhaust emissions and ensure a long catalyst service life. Fit a new spark plug after approx. 100 operating hours or earlier if the electrodes are essential to Using this Manual" 22 BR 340, BR 340 L, BR 420, BR 420 C The ...
.... : Dirty air filter. : Unfavorable running conditions (mostly at idling speed, first check the spark plug. : Remove spark plug - Rectify problems which may only be operated with unleaded gasoline and STIHL two cycle engine oil or equivalent quality two cycle engine oils in a mix ratio of 50:1... condition of the spark plug. see "Guide to minimize harmful exhaust emissions and ensure a long catalyst service life. Fit a new spark plug after approx. 100 operating hours or earlier if the electrodes are essential to Using this Manual" 22 BR 340, BR 340 L, BR 420, BR 420 C The ...
Instruction Manual
Page 24
... and cause a fire. Always press spark plug boot (2) snugly onto spark plug terminal (1) of the muffler. * see "Guide to Using this Manual" BR 340, BR 340 L, BR 420, BR 420 C 23 If the engine is damaged or heavily carbonized, fit a new one. : Install the spark arresting screen (2). : Refit the clip... (1). 12 1 000BA036 TR 373BA031 KN To reduce the risk of fire and burn injury, use only spark plugs authorized by STIHL. Spark ...
... and cause a fire. Always press spark plug boot (2) snugly onto spark plug terminal (1) of the muffler. * see "Guide to Using this Manual" BR 340, BR 340 L, BR 420, BR 420 C 23 If the engine is damaged or heavily carbonized, fit a new one. : Install the spark arresting screen (2). : Refit the clip... (1). 12 1 000BA036 TR 373BA031 KN To reduce the risk of fire and burn injury, use only spark plugs authorized by STIHL. Spark ...
Instruction Manual
Page 29
Complete 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 ...work or daily after about 100 operating hours Clean x Check x Clean or replace x Tighten x Check x Have replaced by a STIHL servicing dealer 28 BR 340, BR 340 L, BR 420, BR 420 C If your daily working time is longer than normal or operating conditions are difficult (very dusty work be done by servicing...
Complete 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 ...work or daily after about 100 operating hours Clean x Check x Clean or replace x Tighten x Check x Have replaced by a STIHL servicing dealer 28 BR 340, BR 340 L, BR 420, BR 420 C If your daily working time is longer than normal or operating conditions are difficult (very dusty work be done by servicing...
Instruction Manual
Page 30
... 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...
... 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...
Instruction Manual
Page 31
... created by enriching mixture. 19. Connects the spark plug to start the engine. 20. Attenuates exhaust noises and diverts exhaust gases away from operator. The grip of fire. 17. For fuel and oil mixture. 30 BR 340, BR 340 L, BR 420, BR 420 C Controls the speed of the user.... 12. Setting Lever. Pleated Hose. Back Padding. For tuning carburetor. 18. Control Handle. Spark Plug Boot. For closing the fuel tank. 21. Nozzle, Straight Aims...
... created by enriching mixture. 19. Connects the spark plug to start the engine. 20. Attenuates exhaust noises and diverts exhaust gases away from operator. The grip of fire. 17. For fuel and oil mixture. 30 BR 340, BR 340 L, BR 420, BR 420 C Controls the speed of the user.... 12. Setting Lever. Pleated Hose. Back Padding. For tuning carburetor. 18. Control Handle. Spark Plug Boot. For closing the fuel tank. 21. Nozzle, Straight Aims...
Instruction Manual
Page 32
x 37.8 in (34 mm) Idle speed: 3,100 rpm Ignition System Type: Electronic magneto ignition Spark plug (suppressed): Bosch WSR 6 F or NGK BPMR 7 A; x 960 mm) 1113 195 8200 Model BR 340 BR 340L BR 420 BR 420 C Bystander noise per ANSI B 175.2-2000 dB(A) 73 68 74 73 Air flow rate CFM (m3/h) 688 (...mm) Stroke: 1.34 in (34 mm) Idle speed: 3,100 rpm BR 420, 420 C Single cylinder two-stroke engine Displacement: 3.45 ci (56.5 cm3) Bore: 1.81 in (46 mm) Stroke: 1.34 in (3.5 mm dia. Electrode gap: 0.02 in (0.5 mm) Spark plug thread: M 14 x 1.25; 0.37 in (9.5 mm) long Fuel...
x 37.8 in (34 mm) Idle speed: 3,100 rpm Ignition System Type: Electronic magneto ignition Spark plug (suppressed): Bosch WSR 6 F or NGK BPMR 7 A; x 960 mm) 1113 195 8200 Model BR 340 BR 340L BR 420 BR 420 C Bystander noise per ANSI B 175.2-2000 dB(A) 73 68 74 73 Air flow rate CFM (m3/h) 688 (...mm) Stroke: 1.34 in (34 mm) Idle speed: 3,100 rpm BR 420, 420 C Single cylinder two-stroke engine Displacement: 3.45 ci (56.5 cm3) Bore: 1.81 in (46 mm) Stroke: 1.34 in (3.5 mm dia. Electrode gap: 0.02 in (0.5 mm) Spark plug thread: M 14 x 1.25; 0.37 in (9.5 mm) long Fuel...
Instruction Manual
Page 35
...oil may be performed either at STIHL Incorporated or at and after the first scheduled replacement point. 34 BR 340, BR 340 L, BR 420, BR 420 C Deviations from this manual are : Carburetor Choke (Cold start enrichment system) Intake manifold Air filter Spark plug Magneto or electronic ignition system (ignition... scheduled replacement point for the warranty period. These warranted parts are based on your engine is defective. Warranty Work STIHL Incorporated shall remedy warranty defects at any emission related part on the application of "repair or replace as required maintenance...
...oil may be performed either at STIHL Incorporated or at and after the first scheduled replacement point. 34 BR 340, BR 340 L, BR 420, BR 420 C Deviations from this manual are : Carburetor Choke (Cold start enrichment system) Intake manifold Air filter Spark plug Magneto or electronic ignition system (ignition... scheduled replacement point for the warranty period. These warranted parts are based on your engine is defective. Warranty Work STIHL Incorporated shall remedy warranty defects at any emission related part on the application of "repair or replace as required maintenance...