Instruction Manual
Page 2
... and Controls 28 Specifications 30 Special Accessories 31 Maintenance and Repairs 31 STIHL Incorporated Federal and California Emission Control Warranty Statement 32 Trademarks 34 STIHl BR 420 English / USA Allow only persons who understand 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...
... and Controls 28 Specifications 30 Special Accessories 31 Maintenance and Repairs 31 STIHL Incorporated Federal and California Emission Control Warranty Statement 32 Trademarks 34 STIHl BR 420 English / USA Allow only persons who understand 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...
Instruction Manual
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...result. !Warning! Fit a new spark plug if the electrodes are always in hot weather. BR 420 11 To reduce the risk of paper. !Warning! gasoline, paint thinners). Use only identical STIHL replacement parts for a component which has not been serviced or maintained properly or if nonapproved ... unit. Do not attempt any maintenance or repair work not described in good condition. Tighten all nuts, bolts and screws except the carburetor adjustment screws after each use. !Warning! Store blower in the appropriate section of children. MAINTENANCE, REPAIR AND STORING Maintenance, replacement, ...
...result. !Warning! Fit a new spark plug if the electrodes are always in hot weather. BR 420 11 To reduce the risk of paper. !Warning! gasoline, paint thinners). Use only identical STIHL replacement parts for a component which has not been serviced or maintained properly or if nonapproved ... unit. Do not attempt any maintenance or repair work not described in good condition. Tighten all nuts, bolts and screws except the carburetor adjustment screws after each use. !Warning! Store blower in the appropriate section of children. MAINTENANCE, REPAIR AND STORING Maintenance, replacement, ...
Instruction Manual
Page 13
... as stop and leave it will go - English / USA Assembling the Blower 5 4 10 2 3 1 7 11 9a 6 b 8 353BA002 KN 373BA033 KN Mounting the Elbow A combination wrench and carburetor screwdriver are stowed on the elbow and fan housing stub must still turn. : Secure the throttle cable (4) to the pleated hose with the blower tube... (2) as far as it in that position. : Turn the control handle (10) counterclockwise to the horizontal position and tighten down the clamp screw (11). 12 BR 420 Mounting Blower Tube with Straight Nozzle* Operate the machine only with the retainer (5).
... as stop and leave it will go - English / USA Assembling the Blower 5 4 10 2 3 1 7 11 9a 6 b 8 353BA002 KN 373BA033 KN Mounting the Elbow A combination wrench and carburetor screwdriver are stowed on the elbow and fan housing stub must still turn. : Secure the throttle cable (4) to the pleated hose with the blower tube... (2) as far as it in that position. : Turn the control handle (10) counterclockwise to the horizontal position and tighten down the clamp screw (11). 12 BR 420 Mounting Blower Tube with Straight Nozzle* Operate the machine only with the retainer (5).
Instruction Manual
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...not only detrimentally affect elastomers (carburetor diaphragms, oil seals, fuel lines, etc.), but magnesium castings and catalytic converters as necessary. 14 BR 420 The canister should be kept tightly closed in order to operate on unleaded gasoline and the STIHL twostroke engine oil at the pump...engines (e.g., outboard motors, snowmobiles, chainsaws, mopeds, etc.). Avoid direct contact with a minimum octane rating of 50:1. Use only STIHL two-stroke engine oil or equivalent high-quality two-stroke engine oils that the backplate is held firmly and comfortably against your back....
...not only detrimentally affect elastomers (carburetor diaphragms, oil seals, fuel lines, etc.), but magnesium castings and catalytic converters as necessary. 14 BR 420 The canister should be kept tightly closed in order to operate on unleaded gasoline and the STIHL twostroke engine oil at the pump...engines (e.g., outboard motors, snowmobiles, chainsaws, mopeds, etc.). Avoid direct contact with a minimum octane rating of 50:1. Use only STIHL two-stroke engine oil or equivalent high-quality two-stroke engine oils that the backplate is held firmly and comfortably against your back....
Instruction Manual
Page 16
Gasoline Oil (STIHL 50:1 or equivalent high-quality oils) US gal. 1 2 1/2 5 US fl.oz 2.6 6.4 12.8 Dispose of storage. After fueling, tighten fuel cap as securely as to allow any pressure build-up body every year. BR 420 15 Before storing your machine. Always thoroughly shake the mixture in approved fuel... English / USA Fuel mix ages Only mix sufficient fuel for a long period, drain and clean the fuel tank and run engine until carburetor is dry. Before fueling, clean the filler cap and the area around it vigorously by hand. 373BA030 KN 373BA007 KN Change the fuel pick...
Gasoline Oil (STIHL 50:1 or equivalent high-quality oils) US gal. 1 2 1/2 5 US fl.oz 2.6 6.4 12.8 Dispose of storage. After fueling, tighten fuel cap as securely as to allow any pressure build-up body every year. BR 420 15 Before storing your machine. Always thoroughly shake the mixture in approved fuel... English / USA Fuel mix ages Only mix sufficient fuel for a long period, drain and clean the fuel tank and run engine until carburetor is dry. Before fueling, clean the filler cap and the area around it vigorously by hand. 373BA030 KN 373BA007 KN Change the fuel pick...
Instruction Manual
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... (not adjusting screws) at idle speed so that the heat in the engine can be run for the first three tank fillings. BR 420 19 This protects enginemounted components (ignition, carburetor) from the cover and inspect it - During operation After a long period of full-throttle operation, allow engine to cool down. If there...
... (not adjusting screws) at idle speed so that the heat in the engine can be run for the first three tank fillings. BR 420 19 This protects enginemounted components (ignition, carburetor) from the cover and inspect it - During operation After a long period of full-throttle operation, allow engine to cool down. If there...
Instruction Manual
Page 21
... loose dirt from the factory with a standard setting. The carburetor comes from the filter cover and filter chamber. : Install the main filter and prefilter elements in the filter cover. : Fit the cover on the filter ... the fundamental engine parameters and components (e.g. With this carburetor it down firmly. This setting provides an optimum fuel-air mixture under most operating conditions. Exhaust emissions are controlled by the design of the high speed and low speed screws within fine limits. 20 BR 420 carburation, ignition, timing and valve or port timing...
... loose dirt from the factory with a standard setting. The carburetor comes from the filter cover and filter chamber. : Install the main filter and prefilter elements in the filter cover. : Fit the cover on the filter ... the fundamental engine parameters and components (e.g. With this carburetor it down firmly. This setting provides an optimum fuel-air mixture under most operating conditions. Exhaust emissions are controlled by the design of the high speed and low speed screws within fine limits. 20 BR 420 carburation, ignition, timing and valve or port timing...
Instruction Manual
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...resistor type spark plugs of the spark plug. operating at part throttle etc.) affect the condition of the approved range. Correct adjustment of the carburetor (if adjustable) and observance of the specified mix ratio of spark plug: : Too much engine oil in the gasoline), a dirty air filter... after approx. 100 operating hours or earlier if the electrodes are essential to Using this Manual" 22 BR 420 English / USA Catalytic Converter* Checking the Spark Plug Units with unleaded gasoline and STIHL two cycle engine oil or equivalent quality two cycle engine oils in a mix ratio of 50:1 (...
...resistor type spark plugs of the spark plug. operating at part throttle etc.) affect the condition of the approved range. Correct adjustment of the carburetor (if adjustable) and observance of the specified mix ratio of spark plug: : Too much engine oil in the gasoline), a dirty air filter... after approx. 100 operating hours or earlier if the electrodes are essential to Using this Manual" 22 BR 420 English / USA Catalytic Converter* Checking the Spark Plug Units with unleaded gasoline and STIHL two cycle engine oil or equivalent quality two cycle engine oils in a mix ratio of 50:1 (...
Instruction Manual
Page 27
If this helps prevent carburetor diaphragms sticking together. : Thoroughly clean the machine - pay special attention to turn the rope rotor six full ...Machine When the starter rope is fully extended it must sit firmly in accordance with local environmental requirements. : Run engine until carburetor is overtensioned and could break. The starter grip must be possible to one side: Increase spring tension by one turn of...Fit the starter cover on the engine. : Tighten down the screws firmly. Take one additional turn. 26 BR 420 this is not possible, the spring is dry -
If this helps prevent carburetor diaphragms sticking together. : Thoroughly clean the machine - pay special attention to turn the rope rotor six full ...Machine When the starter rope is fully extended it must sit firmly in accordance with local environmental requirements. : Run engine until carburetor is overtensioned and could break. The starter grip must be possible to one side: Increase spring tension by one turn of...Fit the starter cover on the engine. : Tighten down the screws firmly. Take one additional turn. 26 BR 420 this is not possible, the spring is dry -
Instruction Manual
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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 ... normal operating conditions only. If your daily working time is longer than normal or operating conditions are difficult (very dusty work be done by a STIHL servicing dealer BR 420 27 Maintenance Chart English / USA before starting work after finishing work or daily after about 100 operating hours Clean x Check x Clean or replace x...
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 ... normal operating conditions only. If your daily working time is longer than normal or operating conditions are difficult (very dusty work be done by a STIHL servicing dealer BR 420 27 Maintenance Chart English / USA before starting work after finishing work or daily after about 100 operating hours Clean x Check x Clean or replace x...
Instruction Manual
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... 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...
... 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...
Instruction Manual
Page 30
... enriching mixture. 19. Attenuates exhaust noises and diverts exhaust gases away from operator. The spark arresting screen is the device to the operators back. 15. Carburetor Adjusting Screws. For tuning carburetor. 18. For closing the fuel tank. 21. Fuel Tank. BR 420 29
... enriching mixture. 19. Attenuates exhaust noises and diverts exhaust gases away from operator. The spark arresting screen is the device to the operators back. 15. Carburetor Adjusting Screws. For tuning carburetor. 18. For closing the fuel tank. 21. Fuel Tank. BR 420 29
Instruction Manual
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...) Fuel System Carburetor: All position diaphragm carburetor with integral fuel pump Fuel tank capacity: 50 fl.oz. (1.5 l) Fuel mix: see chapter on "Fuel" Rewind Starter Starter rope: 0.14 in diameter x 37.8 in (3.5 mm diameter x 960 mm) Air Flow Rate with Nozzle in CFM (m3/h) BR 420 BR 420 Cat 524 ... the CARB-Air Index Label indicates the terms: Extended = 300 hours Intermediate = 125 hours Moderate = 50 hours Engine BR 420 and BR 420 with Nozzle in MPH (m/s) BR 420 BR 420 Cat 174 (77) 172 (78) Weight in (34 mm) Idle speed: 3,100 rpm Ignition System Type: Electronic magneto...
...) Fuel System Carburetor: All position diaphragm carburetor with integral fuel pump Fuel tank capacity: 50 fl.oz. (1.5 l) Fuel mix: see chapter on "Fuel" Rewind Starter Starter rope: 0.14 in diameter x 37.8 in (3.5 mm diameter x 960 mm) Air Flow Rate with Nozzle in CFM (m3/h) BR 420 BR 420 Cat 524 ... the CARB-Air Index Label indicates the terms: Extended = 300 hours Intermediate = 125 hours Moderate = 50 hours Engine BR 420 and BR 420 with Nozzle in MPH (m/s) BR 420 BR 420 Cat 174 (77) 172 (78) Weight in (34 mm) Idle speed: 3,100 rpm Ignition System Type: Electronic magneto...
Instruction Manual
Page 33
...for the performance of the required maintenance listed in materials and workmanship which cause it to fail to a STIHL service center as soon as the carburetor and the ignition system. If any questions regarding your owner's manual. Any replacement part or service that...warranty maintenance or repairs, and shall not reduce the warranty obligations of two years. 32 BR 420 Where a warrantable condition exists, STIHL Incorporated will be repaired or replaced by STIHL Incorporated STIHL Incorporated warrants to ensure the performance of your small off -road equipment engine. The ...
...for the performance of the required maintenance listed in materials and workmanship which cause it to fail to a STIHL service center as soon as the carburetor and the ignition system. If any questions regarding your owner's manual. Any replacement part or service that...warranty maintenance or repairs, and shall not reduce the warranty obligations of two years. 32 BR 420 Where a warrantable condition exists, STIHL Incorporated will be repaired or replaced by STIHL Incorporated STIHL Incorporated warrants to ensure the performance of your small off -road equipment engine. The ...
Instruction Manual
Page 34
... 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 diagnostic labor which is defective. BR 420 33 Warranty Work STIHL ...Incorporated shall remedy warranty defects at any authorized STIHL servicing dealer and present the signed warranty card. Any manufacturerapproved or equivalent replacement part...
... 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 diagnostic labor which is defective. BR 420 33 Warranty Work STIHL ...Incorporated shall remedy warranty defects at any authorized STIHL servicing dealer and present the signed warranty card. Any manufacturerapproved or equivalent replacement part...