Technical Information · issue 11 of 2011
New STIHL BR 350, BR 430 Backpack Blowers
IssueTI 11/2011
Full text
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STIH)
Technical Information 11.2011
New STIHL BR 350, BR 430 Backpack Blowers – Series 4244
Contents
1. Technical Description
2. Specifications
3. Special Accessories
4. Servicing Accessories
5. Service Notes
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)m~ge 2 Technical Information 11.2011
The new BR 350 backpack blower is a reasonably 1. Technical Description
priced and reliable entry-level model in the
professional sector. 1.1 2-Cycle Engine with Stratified
The new BR 430 backpack blower offers high power Scavenging
and convenience. The engine installed in the new blowers uses our
A special feature of the new blowers is the simplified proven 2-cycle technology for fuel-efficient and low
starting procedure – the choke knob and the manual emission operation.
fuel pump need only be operated once for each
start.
Method of operation
The new blowers are powered by the particularly
A buffer of fuel-free air separates the fresh mixture
fuel-efficient, low emission STIHL 2-cycle engine,
and exhaust gas. The air buffer flows into the
which complies with EU II and EPA III.
cylinder ahead of the fresh mixture.
At the start of the scavenging and intake stroke,
Target groups fuel-free air flows into the combustion chamber first
– Landscapers and pushes the exhaust gas into the exhaust port.
The air buffer prevents the subsequent charge of
– Municipalities fresh mixture escaping through the exhaust port.
– Janitorial services The reduction in scavenging loses results in less
– Private users emissions and a lower fuel consumption.
Applications 1.2 Air Filter
– Garden and landscape care Compared to the BR 380 and BR 420, the filter area
– Sports facilities of the new BR 350 and BR 430 blowers is 50%
larger.
– Parks
The new blowers therefore have a longer filter life.
1.3 Blowing Attachment
The blowing attachment must be properly mounted
before the machine is operated – see instruction
manual.
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Technical Information 11.2011 Page 3
1.4 Control Handle
1.4.1 Positions of Setting Lever – BR 350 1.4.2 Positions of Setting Lever – BR 430
1 1
2
2
0009TI002 KN
0009TI004 KN
Run position F Run position F
Engine is running or is ready to start. Throttle Engine is running or is ready to start. Throttle
trigger (2) can be moved to any position. trigger (2) can be moved to any position.
Stop engine † Stop engine †
Ignition is interrupted, until the engine stops. The Ignition is interrupted, until the engine stops. The
setting lever (1) does not remain in this position, i.e. setting lever (1) does not remain in this position, i.e.
it springs back to the run position F. it springs back to the run position F.
The ignition is again ready for operation. The ignition is again ready for operation.
Fixed throttle Lock positions C
The throttle trigger (2) can be locked in three
positions: 1/3 throttle, 2/3 throttle and full throttle.
1
To disengage the lock, move the setting lever (1)
back to the normal run position F.
2
0009TI003 KN
The throttle trigger (2) can be locked in any position
by operating the setting lever (1).
To disengage the lock:
Return the setting lever (1) to the run position F.
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1.5 Starting Procedure 1.6 Retainer for Blower Tube (BR 430)
Centralized controls for start. Velcro strap secures blower tube to carrying handle
for storage and transportation.
Choke knob is used to select starting throttle
position.
Choke knob returns automatically to the normal run
position e when the throttle trigger is operated.
. Setting lever on control handle must be in run
position F.
0009TI005 KN
. Press fuel pump bulb at least 8 times.
0009TI006 KN
Cold engine
. Turn choke knob to c.
. Continue cranking until engine runs.
Warm engine
. Turn choke knob to o.
. Continue cranking until engine runs.
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Technical Information 11.2011 Page 5
2. Specifications
2.1 Engine
STIHL single cylinder two-stroke engine with stratified scavenging
Displacement: 3.86 cu. in. (63.3 cm³)
Bore: 1.89 in. (48 mm)
Stroke: 1.38 in. (35 mm)
Idle speed: 3000 rpm
Engine power to ISO 7293:
BR 350: 2.1 kW (2.8 bhp)
BR 430: 2.9 kW (3.9 bhp)
2.2 Fuel System
2.2.1 Carburetor
BR 350
Standard setting with limiter cap on the high speed screw (H):
High speed screw H: Turn counterclockwise as far as stop – no more than
3/4 (12/16) turn
Low speed screw L: Open 1 1/2 (24/16) turns
Basic setting without limiter cap:
High speed screw H: Open 1 1/2 (24/16) turns
Low speed screw L: Open 1 1/2 (24/16) turns
BR 430
Standard setting with limiter cap on the high speed screw (H):
High speed screw H: Turn counterclockwise as far as stop – no more than
3/4 (12/16) turn
Low speed screw L: Open 1 (16/16) turn
Basic setting without limiter cap:
High speed screw H: Open 1 1/2 (24/16) turns
Low speed screw L: Open 1 (16/16) turn
2.2.2 Fuel Tank
Fuel tank capacity: 57.5 fl oz (1.7 l)
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2.3 Blower Data
BR 350 BR 430
Air velocity: 168 mph (75 m/s) 183 mph (82 m/s)
Maximum air flow rate: 677 cf/min (1150 m³/h) 765 cf/min (1300 m³/h)
Air flow rate with nozzle: 441 cf/min (750 m³/h) 500 cf/min (850 m³/h)
2.4 Ignition System 2.5 Weight
Spark plug (resistor NGK BPMR 7 A dry
type):
BR 350: 22 lbs (10.0 kg)
Electrode gap: 0.020 in. (0.5 mm)
BR 430: 22.3 lbs (10.1 kg)
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3. Special Accessories
Part Name Part No. Description
Chest strap 0000 790 7700 For snug fitting shoulder straps.
Hip belt 4203 710 9102 Distributes weight evenly. For longer periods of low-
fatigue operation.
Special accessories for BR 350
Part Name Part No. Description
Round nozzle, curved 4203 708 6300 For effective use with airstream parallel to ground.
Fan nozzle, curved 4203 701 8300 Broad airstream close to ground for large area use.
Control handle 4244 790 1308 Control handle with antistatic system
Special accessories for BR 430
Part Name Part No. Description
Round nozzle, curved 4282 708 6365 For effective use with airstream parallel to ground.
Fan nozzle, curved 4282 708 6340 Broad airstream close to ground for large area use.
Heavy-duty kit 4282 007 1017 For operation in very dry and dusty conditions –
contains blower tubes with graphite to discharge static
electricity and an attachment for the blower tube to
avoid electrostatic effects.
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4. Servicing Accessories
4.1 Servicing Aids
Part Name Part No. Application
Lubricating grease – 225 g tube 0781 120 1111 Oil seals, sliding and bearing points
STIHL press fluid OH 723 0781 957 9000 Rubber elements, fuel hoses, etc.
Dirko HT red sealant 0783 830 2000 Engine pan, oil seals (outside)
Standard commercial solvent- Cleaning sealing faces and carburetor, crankshaft stubs
based degreasant containing no and flywheel taper
chlorinated or halogenated
hydrocarbons
4.2 Special Servicing Tools
No new special tools are required for models
BR 350, 430.
Existing special servicing tools are listed in the
service manual for the STIHL BR 350, 430.
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5. Service Notes 5.4 Repair Times
If the machine is started in the course of repairs, it is The specified repair times assume that the work is
essential to observe all country-specific safety performed by trained personnel in a properly
regulations and the safety precautions in the equipped service workshop.
instruction manual. Repair times are quoted in minutes.
Repair procedure BR 350
BR 430
5.1 Service Manual
2 Replace crankcase, crankcase
The STIHL BR 350, 430 service manual is available gasket or re-seal crankcase.
for servicing and repairs. Includes air leak test. 100
3 Replace crankshaft main bearing(s).
Includes air leak test. 100
5.2 Tightening Torques 4 Replace crankshaft seal(s). Includes
Tightening torques are listed in the service manual air leak test. 60
for the STIHL BR 350, 430. 5 Replace tank filler cap. 3
6 Replace cylinder and/or piston.
Includes air leak test and diagnosis
5.3 Location of Serial Number and repair of component(s) that
caused failure. 100
7 Replace ignition module. Includes
stop circuit test. 25
8 Replace fuel tank line, tank vent, or
fuel pick-up body. 25
9 Replace intake manifold or intake
flange. 25
10 Repair or replace carburetor.
Includes fuel system testing. 30
0009TI007 KN
11 Repair throttle control. 20
12 Repair or replace rewind starter. 15
13 Replace fan wheel. 30
The serial number is applied to the blower housing 14 Replace muffler. 25
and cylinder. 15 Replace air filter or filter housing. 20
16 Repair or replace stop switch.
Includes circuit testing. 25
17 Replace fan housing. 50
18 Replace pleated tube. 20
19 Replace air discharge tube or elbow. 15
20 Replace back plate. 15
21 Replace shoulder strap(s) 15
22 Replace fuel tank. 25
35 Engine diagnosis only to determine
failures requiring unit replacement. 25
40 Miscellaneous repairs and other
repairs not listed. 15
45 Handling allowance only-no labor. 5
50 No labor. 0
© ANDREAS STIHL AG & Co. KG, 2011 Technical Documentation
D1/MTK-er
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