Instruction Manual
Page 2
... Chart 34 Parts and Controls 35 Specifications 37 Special Accessories 38 Maintenance and Repairs 38 STIHL Incorporated Federal Emission Control Warranty Statement 39 Trademarks 41 STIHl SR 340, SR 420 English / USA Allow only persons who understand this Manual, please contact your mistblower. ... Mistblowing 25 Cleaning the Air Filter 26 Motor Management 27 Adjusting the Carburetor 27 Spark Arresting Screen in this Manual. !Warning! J6. BA_SE_004_007_01_05.fm Contents Guide to operate your STIHL dealer for information and assistance. 1 Printed in this Manual to Using...
... Chart 34 Parts and Controls 35 Specifications 37 Special Accessories 38 Maintenance and Repairs 38 STIHL Incorporated Federal Emission Control Warranty Statement 39 Trademarks 41 STIHl SR 340, SR 420 English / USA Allow only persons who understand this Manual, please contact your mistblower. ... Mistblowing 25 Cleaning the Air Filter 26 Motor Management 27 Adjusting the Carburetor 27 Spark Arresting Screen in this Manual. !Warning! J6. BA_SE_004_007_01_05.fm Contents Guide to operate your STIHL dealer for information and assistance. 1 Printed in this Manual to Using...
Instruction Manual
Page 15
... kinked during assembly. Do not operate your power tool if the muffler is already connected and must still turn. 14 SR 340, SR 420 Tighten all nuts, bolts and screws, except the carburetor adjustment screws, after each use. Store the power tool in a dry and high or locked location out of reach... and carburetor screwdriver are always clean and in hot or dry weather. Do not attempt any maintenance of the emission control system please refer to the maintenance chart and to reduce the risk of the machine. : Line up the stops on the underside of fire, never operate your STIHL servicing...
... kinked during assembly. Do not operate your power tool if the muffler is already connected and must still turn. 14 SR 340, SR 420 Tighten all nuts, bolts and screws, except the carburetor adjustment screws, after each use. Store the power tool in a dry and high or locked location out of reach... and carburetor screwdriver are always clean and in hot or dry weather. Do not attempt any maintenance of the emission control system please refer to the maintenance chart and to reduce the risk of the machine. : Line up the stops on the underside of fire, never operate your STIHL servicing...
Instruction Manual
Page 18
... of highquality gasoline and quality two-stroke air cooled engine oil. Some fuel additives not only detrimentally affect elastomers (carburetor diaphragms, oil seals, fuel lines, etc.), but magnesium castings and catalytic converters as necessary. This could cause running...SR 420 17 Avoid direct contact with a minimum octane rating of the mid-grade gasoline in or on a vehicle. The machine's fuel tank and the canister in approved fuel-canisters only. When mixing, pour oil into the mixture. Fuel English / USA This engine is certified to operate on unleaded gasoline and the STIHL...
... of highquality gasoline and quality two-stroke air cooled engine oil. Some fuel additives not only detrimentally affect elastomers (carburetor diaphragms, oil seals, fuel lines, etc.), but magnesium castings and catalytic converters as necessary. This could cause running...SR 420 17 Avoid direct contact with a minimum octane rating of the mid-grade gasoline in or on a vehicle. The machine's fuel tank and the canister in approved fuel-canisters only. When mixing, pour oil into the mixture. Fuel English / USA This engine is certified to operate on unleaded gasoline and the STIHL...
Instruction Manual
Page 19
... canister before starting, check the air intakes between the backplate and powerhead for a long period, drain and clean the fuel tank and run engine until carburetor is moved to the idle position. : Move the setting lever to ensure that no dirt falls into the tank. Before storing your machine. After fueling... disconnects itself automatically when the setting lever is dry. Before fueling, clean the filler cap and the area around it to the idle position. 18 SR 340, SR 420
... canister before starting, check the air intakes between the backplate and powerhead for a long period, drain and clean the fuel tank and run engine until carburetor is moved to the idle position. : Move the setting lever to ensure that no dirt falls into the tank. Before storing your machine. After fueling... disconnects itself automatically when the setting lever is dry. Before fueling, clean the filler cap and the area around it to the idle position. 18 SR 340, SR 420
Instruction Manual
Page 28
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 ... timing) without the addition of the fundamental engine parameters and components (e.g. This setting provides an optimum fuel-air mixture under most operating conditions. With this carburetor it down firmly. SR 340, SR 420 27 Exhaust emissions are controlled by the design of any major hardware. Motor Management English / USA Adjusting the...
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 ... timing) without the addition of the fundamental engine parameters and components (e.g. This setting provides an optimum fuel-air mixture under most operating conditions. With this carburetor it down firmly. SR 340, SR 420 27 Exhaust emissions are controlled by the design of any major hardware. Motor Management English / USA Adjusting the...
Instruction Manual
Page 34
... spring is overtensioned and could result in accordance with local environmental requirements. : Drain and clean the container. : Run engine until carburetor is fully extended it must be possible to rotate the rotor at least another half turn of the rope off the rotor. :...machine in a dry, high or locked location - If this helps prevent carburetor diaphragms sticking together. : Thoroughly clean the machine - UV rays can make the container material brittle, which could break. English / USA SR 340, SR 420 33 Take one turn . pay special attention to direct sunlight for unnecessarily ...
... spring is overtensioned and could result in accordance with local environmental requirements. : Drain and clean the container. : Run engine until carburetor is fully extended it must be possible to rotate the rotor at least another half turn of the rope off the rotor. :...machine in a dry, high or locked location - If this helps prevent carburetor diaphragms sticking together. : Thoroughly clean the machine - UV rays can make the container material brittle, which could break. English / USA SR 340, SR 420 33 Take one turn . pay special attention to direct sunlight for unnecessarily ...
Instruction Manual
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... Clean Replace x x Pickup body in fuel tank Check Fit new filter x x x Fuel tank Clean x Check idle setting x x Carburetor Readjust idle x Readjust electrode gap x Spark plug Replace after 100 hours of operation Cooling air intakes Clean x Spark arresting screen in muffler ...inspection x Have replaced by dealer 1) x x x Check x x Blower air intake screen Clean x Safety labels Replace x 1) STIHL recommends a STIHL servicing dealer 34 SR 340, SR 420 before starting work after finishing work area etc.), shorten the specified intervals accordingly.
... Clean Replace x x Pickup body in fuel tank Check Fit new filter x x x Fuel tank Clean x Check idle setting x x Carburetor Readjust idle x Readjust electrode gap x Spark plug Replace after 100 hours of operation Cooling air intakes Clean x Spark arresting screen in muffler ...inspection x Have replaced by dealer 1) x x x Check x x Blower air intake screen Clean x Safety labels Replace x 1) STIHL recommends a STIHL servicing dealer 34 SR 340, SR 420 before starting work after finishing work area etc.), shorten the specified intervals accordingly.
Instruction Manual
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Parts and Controls 15 15 25 SR 340, SR 420 372BA022 KN 372BA011 KN English / USA 16 17 18 24 20 19 # 21 22 23 1 Baffle screen 2 Standard nozzle 3 Metering knob 4 Extension tube 5 Throttle trigger 6 ... Harness 12 Back plate 13 Back padding 14 Air filter housing 15 Antivibration elements 16 Container filler cap 17 Container 18 Spark plug boot 19 Carburetor adjusting screws 20 Choke knob 21 Fuel filler cap 22 Starter grip 23 Fuel tank 24 Muffler (depending on country with spark arresting screen) 25...
Parts and Controls 15 15 25 SR 340, SR 420 372BA022 KN 372BA011 KN English / USA 16 17 18 24 20 19 # 21 22 23 1 Baffle screen 2 Standard nozzle 3 Metering knob 4 Extension tube 5 Throttle trigger 6 ... Harness 12 Back plate 13 Back padding 14 Air filter housing 15 Antivibration elements 16 Container filler cap 17 Container 18 Spark plug boot 19 Carburetor adjusting screws 20 Choke knob 21 Fuel filler cap 22 Starter grip 23 Fuel tank 24 Muffler (depending on country with spark arresting screen) 25...
Instruction Manual
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English / USA Definitions 1 Baffle screen. For spraying, dusting or spreading in an emergency. 36 SR 340, SR 420 Increases carrying comfort. 14 Air filter housing. For closing the container. 17 Container. For varying the spraying rate. 4 Extension tube. Controls the speed ... Container filler cap. Sets the trottle to be sprayed. 18 Spark plug boot. Elements designed to start the engine. 23 Fuel tank. For tuning carburetor. 20 Choke knob. The spark arresting screen is the device to reduce the transmission of the engine. 6 Setting lever. To vary the direction and...
English / USA Definitions 1 Baffle screen. For spraying, dusting or spreading in an emergency. 36 SR 340, SR 420 Increases carrying comfort. 14 Air filter housing. For closing the container. 17 Container. For varying the spraying rate. 4 Extension tube. Controls the speed ... Container filler cap. Sets the trottle to be sprayed. 18 Spark plug boot. Elements designed to start the engine. 23 Fuel tank. For tuning carburetor. 20 Choke knob. The spark arresting screen is the device to reduce the transmission of the engine. 6 Setting lever. To vary the direction and...
Instruction Manual
Page 38
...NGK BPMR 7 A; 0.02 in (0.5 mm) Spraying Attachment Container capacity: 3.4 gal (13 l) Size of filler strainer mesh: 0.04 in (1 mm) Discharge rate SR 340: SR 420: 0.03-0.7 gpm (0.13-2.78 l/min) 0.04-0.8 gpm (0.14-3.03 l/min) (infinitely variable) Quantity left in container: 0.026 gal (0.1 l) (design related)... Label indicates the terms: Extended = 300 hours, Intermediate = 125 hours, Moderate = 50 hours Fuel System Carburetor: Fuel tank capacity: Fuel mix: All position diaphragm carburetor with nozzle SR 340: 418 cfm (710 m3/h) SR 420: 441 cfm (750 m3/h) SR 340, SR 420 37
...NGK BPMR 7 A; 0.02 in (0.5 mm) Spraying Attachment Container capacity: 3.4 gal (13 l) Size of filler strainer mesh: 0.04 in (1 mm) Discharge rate SR 340: SR 420: 0.03-0.7 gpm (0.13-2.78 l/min) 0.04-0.8 gpm (0.14-3.03 l/min) (infinitely variable) Quantity left in container: 0.026 gal (0.1 l) (design related)... Label indicates the terms: Extended = 300 hours, Intermediate = 125 hours, Moderate = 50 hours Fuel System Carburetor: Fuel tank capacity: Fuel mix: All position diaphragm carburetor with nozzle SR 340: 418 cfm (710 m3/h) SR 420: 441 cfm (750 m3/h) SR 340, SR 420 37
Instruction Manual
Page 40
.... SR 340, SR 420 39 In the U.S. EPA standards for California: STIHL Incorporated Federal Emission Control Warranty Statement Your Warranty Rights and Obligations The U.S. Also included may be designed, built and equipped, at no abuse, neglect or improper maintenance of your small off-road equipment engine to a STIHL service center as soon as the carburetor and...
.... SR 340, SR 420 39 In the U.S. EPA standards for California: STIHL Incorporated Federal Emission Control Warranty Statement Your Warranty Rights and Obligations The U.S. Also included may be designed, built and equipped, at no abuse, neglect or improper maintenance of your small off-road equipment engine to a STIHL service center as soon as the carburetor and...
Instruction Manual
Page 41
...STIHL servicing dealer. Any manufacturer-approved or equivalent replacement part may be used for any warranty maintenance or repairs on emission-related parts and must be charged for diagnostic labor which is scheduled for required maintenance at and after the first scheduled replacement point. 40 SR 340, SR 420...that part. Maintenance Requirements 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) Intake manifold Air filter Spark...
...STIHL servicing dealer. Any manufacturer-approved or equivalent replacement part may be used for any warranty maintenance or repairs on emission-related parts and must be charged for diagnostic labor which is scheduled for required maintenance at and after the first scheduled replacement point. 40 SR 340, SR 420...that part. Maintenance Requirements 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) Intake manifold Air filter Spark...