Stihl BR 500 User manual

STIH)
STIHL BR 500, 550, 600 2009-05
RA_452_00_01_02.book Seite 0 Donnerstag, 16. Februar 2012 11:52 11

1BR 500, BR 550, BR 600
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© ANDREAS STIHL AG & Co. KG, 2009
Contents
1. Introduction 2
2. Safety Precautions 2
3. Specifications 3
3.1 Engine 3
3.2 Ignition System 3
3.3 Fuel System 3
3.4 Tightening Torques 4
4. Troubleshooting 6
4.1 Rewind Starter 6
4.2 Ignition System 7
4.3 Carburetor 8
4.4 Engine 10
5. Rewind Starter /
Shroud 11
5.1 General 11
5.2 Removing
and Installing 11
5.3 Pawl 11
5.4 Rope Rotor 12
5.5 Starter Rope/Grip 13
5.6 Rope Guide Bushing 14
5.7 Replacing
the Rewind Spring 14
5.8 Tensioning
the Rewind Spring 15
5.9 Shroud 16
6. Fuel System 17
6.1 Air Filter 17
6.2 Carburetor 19
6.2.1 Leakage Test 19
6.2.2 Removing
and Installing 20
6.3 Servicing
the Carburetor 20
6.3.1 Metering Diaphragm 20
6.3.2 Inlet Needle 21
6.3.3 Pump Diaphragm 22
6.3.4 Accelerator Pump 23
6.4 Adjusting
the Carburetor 25
6.4.1 User Adjustment 25
6.4.2 Basic Setting in
Service Shop 26
6.5 Tank Vent 27
6.6 Fuel Hoses/
Pickup Body 28
6.7 Fuel Tank 29
7. Engine 29
7.1 Compression
Pressure 29
7.2 Checking / Adjusting
Valve Clearances 30
7.3 Rocker Arms /
Pushrods 31
7.4 Cam Followers 32
7.5 Cam Gear 33
7.5.1 Decompression
System 33
7.6 Muffler/Spark
Arresting Screen 34
7.7 Flywheel 35
7.8 Testing for Leaks 35
7.8.1 Preparations 36
7.8.2 Vacuum Test 36
7.8.3 Pressure Test 37
7.9 Crankshaft 38
7.9.1 Oil Seals 38
7.9.2 Crankcase,
Lower Half 39
7.9.3 Crankshaft 40
7.9.4 Piston 40
7.9.5 Piston Rings 42
7.9.6 Valves / Valve
Springs 43
7.9.7 Upper Half of
Crankcase
with Cylinder 43
8. Ignition System 44
8.1 Ignition Module 45
8.2 Ignition Timing 45
8.3 Testing the
Ignition Module 45
8.4 Removing and
Installing 46
8.5 Spark Plug Boot 47
8.6 Testing the
Wiring Harness 48
8.7 Ignition System
Troubleshooting 49
9. Control Handle 52
9.1 Throttle Trigger/
Interlock Lever 52
9.2 Setting Lever 52
9.3 Throttle Cable 53
9.3.1 Removing and
Installing 53
9.3.2 Adjusting 53
10. AV System 54
10.1 Spring Elements 54
10.2 Backplate 54
11. Fan 55
11.1 Outer Fan Housing 55
11.2 Inner Fan Housing 56
11.3 Fanwheel 56
11.4 Antistatic Wire 57
12. Special
Servicing Tools 58
13. Servicing Aids 59
RA_452_00_01_02
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2BR 500, BR 550, BR 600
This service manual contains
detailed descriptions of all the
typical repair and servicing
procedures for this power tool.
As the design concept of models
BR 500, BR 550 and BR 600 is
almost identical, the descriptions
and servicing procedures in this
manual generally apply to all three
models. Differences are described
in detail.
You should make use of the
illustrated parts lists while carrying
out repair work. They show the
installed positions of the individual
components and assemblies.
Refer to the latest edition of the
relevant parts list to check the part
numbers of any replacement parts.
A fault on the machine may have
several causes. To help locate the
fault, consult the chapter on
"Troubleshooting" in this manual
and the "STIHL Service Training
System" for all assemblies.
Refer to the “Technical Information”
bulletins for engineering changes
which have been introduced since
publication of this service manual.
Technical information bulletins also
supplement the parts list until an
updated edition is issued.
The special servicing tools
mentioned in the descriptions are
listed in the chapter "Special
Servicing Tools" of this manual.
Use the part numbers to identify the
tools in the "STIHL Special Tools”
manual. The manual lists all special
servicing tools currently available
from STIHL.
Symbols are included in the text and
pictures for greater clarity.
The meanings are as follows:
In the descriptions:
:= Action to be taken as
shown in the illustration
(above the text)
– = Action to be taken that is
not shown in the illustration
(above the text)
In the illustrations:
APointer
aDirection of movement
b4.2
Reference to another chapter,
i.e. chapter 4.2 in this example.
Service manuals and technical
information bulletins are intended
exclusively for the use of properly
equipped repair shops. They must
not be passed to third parties.
Always use original STIHL
replacement parts.
They can be identified by the
STIHL part number,
the STIH) logo and the
STIHL parts symbol (
This symbol may appear alone on
small parts.
If the engine is started up in the
course of repairs or maintenance
work, observe all local and country-
specific safety regulations as well
as the safety precautions and
warnings in the instruction manual.
Gasoline is an extremely flammable
fuel and can be explosive in certain
conditions.
Improper handling may result in
burns or other serious injuries.
Warning!
Do not bring any fire, flame, spark or
other source of heat near the fuel.
All work with fuel must be performed
outdoors only. Spilled fuel must be
wiped away immediately.
1. Introduction 2. Safety Precautions
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3BR 500, BR 550, BR 600
3. Specifications
BR 500 BR 550 BR 600
3.1 Engine
Displacement: 64.8 cm3 (3.95 ci) 64.8 cm3 (3.95 ci) 64.8 cm3(3.95 ci)
Bore: 50 mm (2.55 in) 50 mm (2.55 in) 50 mm (2.55 in)
Stroke: 33 mm (1.3 in) 33 mm (1.3 in) 33 mm (1.3 in)
Operating speed with nozzle: 5500 rpm 6100 rpm 7200 rpm
Idle speed: 2500 rpm 2500 rpm 2500 rpm
Crankcase leakage test
at gauge pressure: 0.5 bar 0.5 bar 0.5 bar
under vacuum: 0.5 bar 0.5 bar 0.5 bar
3.2 Ignition System
Air gap between ignition module and fanwheel: 0.15...0.3 mm
(0.006...0.012 in)
0.15...0.3 mm
(0.006...0.012 in)
0.15...0.3 mm
(0.006...0.012 in)
Spark plug: NGK CMR 6 H NGK CMR 6 H NGK CMR 6 H
Electrode gap: 0.7 mm (0.028 in) 0.7 mm (0.028 in) 0.7 mm (0.028 in)
3.3 Fuel System
Carburetor leakage test at gauge pressure: 0.8 bar 0.8 bar 0.8 bar
Operation of tank vent at gauge pressure: 0.3 bar 0.3 bar 0.3 bar
Fuel: as specified in
instruction manual
as specified in
instruction manual
as specified in
instruction manual
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4BR 500, BR 550, BR 600
3.4 Tightening Torques
DG and P (Plastoform) screws are used in polymer and lightmetal components. These screws form a permanent
thread when they are installed for the first time. They can be removed and installed as often as necessary
without impairing the strength of the screwed assembly, providing the specified tightening torque is observed.
For this reason it is essential to use a torque wrench.
Fastener Thread size For component Torque Remarks
lbf.ft Nm
Screw IS-P5x18 Shroud/filter housing/fan housing 3.0 4.0
Screw IS-P5x18 Shroud/fan housing 3.0 4.0
Collar screw IS-M5x16 Collar screw/cylinder/rocker arm
mounting 6.6 9.0 1)
Screw IS-DG5x16 Cover/cylinder 3.0 4.0
Screw IS-M5x21 Filter cover/filter housing 3.0 4.0
Screw IS-M5x48x22 Filter housing/carburetor/flange 4.4 6.0
Screw IS-P5x18 Fan housing, outer/inner 3.0 4.0
Screw IS-D6x32 Fan housing, inner/engine pan 8.8 12.0
Screw IS-D6x32 Fan housing, inner/cylinder 8.8 12.0
Hub IS-M12x1 Fanwheel/crankshaft 22.0 30.0 2)
Screw IS-P4x19 Handle molding, outer/inner 1.1 1.5
Screw IS-P6x21.5 Handle moldings/blower tube 3.0 4.0
Screw IS-M4x9.5 Scoop/muffler 3.0 4.0
Screw IS-M6x30 Engine pan/cylinder, initial stage 3.0 4.0 3)
Screw IS-M6x30 Engine pan/cylinder, final stage 8.8 12.0 3)
Screw IS-DG5x24 Air guide shroud/fan housing 3.0 4.0
Screw IS-DG5x24 Air guide shroud/engine pan 4.4 6.0
Screw IS-P4x19 Detent spring/handle molding, inner 1.1 1.5
Screw IS-P6x25 Backplate/bearing plug 4.4 6.0
Screw IS-P6x25 Backplate/tank housing 4.4 6.0
Screw IS-M5x18 Muffler/cylinder 5.9 8.0
Screw IS-P6x21.5 Hose clip/blower attachment 3.0 4.0
Nut IS-M8x1 Flywheel/crankshaft 15.0 20.0
Locknut IS-M5 Rocker arm mounting
Screw IS-M5x18 Starter cover/shroud/engine pan 4.4 6.0
Screw IS-M5x18 Starter cover/shroud/cylinder 4.4 6.0
Remarks:
1) Install with high-strength Loctite 270
2) Do not lubricate with grease
3) Tighten in crosswise pattern
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5BR 500, BR 550, BR 600
Fastener Thread size For component Torque Remarks
lbf.ft Nm
Screw IS-P5x14 Harness/backplate 3.0 4.0
Screw IS-M5x30 Valve cover/cylinder 4.4 6.0
Spark plug IS-M10x1 Spark plug 6.6 9.0
Screw IS-DG5x20 Ignition module/cylinder 4.4 6.0
Use the following procedure when refitting a DG or P screw in an existing thread:
Place the screw in the hole and rotate it counterclockwise until it drops down slightly. Tighten the screw
clockwise to the specified torque.
This procedure ensures that the screw engages properly in the existing thread and does not form a new thread
and weaken the assembly.
Power screwdriver settings for
polymer: Plastoform screws max. 600 rpm
DG screws max. 500 rpm
Important:
Do not mix up screws with and without binding head
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6BR 500, BR 550, BR 600
4. Troubleshooting
4.1 Rewind Starter
Condition Cause Remedy
Starter rope broken Rope pulled out too vigorously as
far as stop or over edge, i.e. not
vertically
Fit new starter rope
Normal wear Fit new starter rope
Starter rope does not rewind Rewind spring broken Fit new rewind spring
Spring overtensioned – no reserve
when rope is fully extended
Fit new rewind spring
Very dirty or corroded Clean or replace rewind spring
Starter rope can be pulled out
almost without resistance
(crankshaft does not turn)
Guide pegs on pawls or pawls
themselves are worn
Fit new pawls
Spring clip fatigued Fit new spring clip
Starter rope is difficult to pull and
rewinds very slowly
Starter mechanism very dirty Thoroughly clean complete starter
mechanism
Lubricating oil on rewind spring
becomes viscous at very low
outside temperatures (spring
windings stick together)
Coat rewind spring with a standard
solvent-based degreasant
(containing no chlorinated or
halogenated hydrocarbons). Then
pull rope carefully several times
until normal action is restored.
When installing, coat rewind spring
and starter post with STIHL special
lubricant
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7BR 500, BR 550, BR 600
4.2 Ignition System
Exercise extreme caution while carrying out maintenance and repair work on the ignition system. The high
voltages which occur can cause serious or fatal injuries!
Condition Cause Remedy
Engine runs roughly, misfires,
temporary low of power
Spark plug boot is loose Press boot firmly onto spark plug,
and fit a new leg spring if necessary
Spark covered in soot, smeared
with oil
Install new spark plug
Wrong air gap between ignition coil
and flywheel
Reset air gap
Flywheel cracked or damaged or
pole shoes have turned blue
Install new flywheel
Ignition timing out of adjustment,
flywheel warped, key in flywheel
sheared
Install new flywheel
Flywheel magnetization weak –
pole shoes have turned blue
Install new flywheel
Engine does not run No spark Check operation of setting lever
and ignition module
No spark Faulty insulation on ignition lead or
short circuit wire. Use ohmmeter to
check ignition lead for break. If
break is detected or resistance is
high, fit new ignition lead
Replace or clean spark plug,
replace damaged parts of ignition
system
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8BR 500, BR 550, BR 600
4.3 Carburetor
Condition Cause Remedy
Carburetor floods, engine stalls Inlet needle not sealing. Foreign
matter in valve seat or cone
damaged
Remove and clean or replace inlet
needle, clean fuel tank, pickup
body and fuel line if necessary
Inlet control lever sticking on
spindle
Free off inlet control lever
Helical spring not located on nipple
of inlet control lever
Remove inlet control lever and refit
correctly
Perforated disc on diaphragm is
deformed and presses constantly
against inlet control lever
Fit new metering diaphragm
Inlet control lever too high (relative
to design position)
Set inlet control lever flush with
upper face of housing
Poor acceleration Idle jet too lean Turn low speed screw (L)
counterclockwise (richer) no further
than stop
Main jet too lean Turn high speed screw (H)
counterclockwise (richer) no further
than stop
Inlet control lever too low (relative
to design position)
Set inlet control lever flush with
upper face of housing
Inlet needle sticking to valve seat Remove inlet needle, clean
and refit
Diaphragm gasket leaking Fit new diaphragm gasket
Metering diaphragm damaged or
shrunk
Fit new metering diaphragm
Impulse hose damaged or kinked Fit new impulse hose
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9BR 500, BR 550, BR 600
Condition Cause Remedy
Engine will not idle,
idle speed too high
Throttle shutter opened too wide by
idle speed screw (LA), throttle
cable adjustment incorrect
Reset idle speed screw (LA), check
throttle cable adjustment
Engine leaking Seal the engine
Engine stalls at idle speed Idle jet bores or ports blocked Clean jets and ports and blow clear
with compressed air
Idle jet too rich or too lean Set low speed screw (L) correctly
Setting of idle speed screw
incorrect – throttle shutter
completely closed
Set idle speed screw (LA) correctly
Small plastic disc in valve jet does
not close
Clean or renew valve jet
Engine speed drops quickly under
load – low power
Air filter plugged Clean air filter
Throttle shutter not opened fully Check throttle cable adjustment
Tank vent faulty Clean or replace tank vent if
necessary
Fuel pickup body dirty Clean or replace pickup body
Fuel strainers dirty Fit new fuel strainers
Leak in fuel line between tank and
fuel pump
Seal or renew connections and fuel
line
Setting of high speed screw (H) too
rich
Turn high speed screw (H)
clockwise (leaner), no further than
stop
Main jet bores or ports blocked Clean the carburetor
Pump diaphragm damaged or
fatigued
Fit new pump diaphragm
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10 BR 500, BR 550, BR 600
4.4 Engine
Always check and, if necessary, repair the following parts before looking for faults on the engine:
– Air filter
– Fuel system
– Carburetor
– Ignition system
Condition Cause Remedy
Engine does not start easily, stalls
at idle speed, but operates normally
at full throttle
Check compression Check combustion chamber
for excessive build-up of
combustion deposits, check
condition of valves and valve
clearance
Manifold leaking Seal or replace manifold
Oil seals on crankshaft defective Replace oil seals
Seal between cylinder and engine
pan leaking/damaged (cracks)
Seal or replace engine pan
Decompression lever sticking Install new cam gear
Engine does not deliver full power
or runs erratically
Piston rings worn or broken Install new piston rings
Muffler / spark arresting screen (if
fitted) carbonized
Clean muffler (inlet and
exhaust openings), replace
spark arresting screen
(if fitted)
Secondary air seepage through
faulty flange or manifold
Replace faulty parts
Air filter element dirty Fit new air filter element
Fuel / impulse line kinked or
cracked
Fit new lines or position
without kinks
Pump diaphragm torn Install new pump diaphragm
Decompression lever sticking Install new cam gear
Engine pan defective (cracks) Replace engine pan
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11BR 500, BR 550, BR 600
If the action of the starter rope
becomes very stiff and the rope
rewinds very slowly or not
completely, it can be assumed that
the starter mechanism is in order
but plugged with dirt. At very low
outside temperatures the lubricating
oil on the rewind spring may thicken
and cause the spring windings to
stick together. This has a
detrimental effect on the function of
the starter mechanism. In such a
case it is sufficient to apply a few
drops of a standard solvent-based
degreasant (containing no
chlorinated or halogenated
hydrocarbons) to the rewind spring.
Carefully pull out the starter rope
several times and allow it to rewind
until its normal smooth action is
restored.
If clogged with dirt or pitch, the
entire starter mechanism, including
the rewind spring, must be removed
and disassembled. Take particular
care when removing the spring.
Lubricate the rewind spring and
starter post with STIHL special
lubricant, b13, before installing.
:Take out the screws (arrows).
:Remove the starter cover with
rewind starter (1).
Install in the reverse sequence.
452RA000
VA
1
– Remove the starter cover with
rewind starter, b5.2
:Ease the spring clip (1) off the
starter post starter post.
:Pull the pawls (2) out of the rope
rotor.
452RA004
1
VA
2
Install in the reverse sequence.
– Lubricate pegs on pawls with
grease, b13.
5. Rewind Starter / Shroud
5.1 General
5.2 Removing and Installing 5.3 Pawl
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12 BR 500, BR 550, BR 600
– Troubleshooting, b4.1
Relieving tension of rewind
spring
The rewind spring will not be under
tension if the starter rope is broken.
– Pull out the starter rope about
5 cm and hold the rope rotor
steady.
– While still holding the rotor
steady, take three turns of the
rope off the rotor.
– Pull out the starter rope and then
slowly let go of the rotor.
– Remove the pawls, b5.3
:Remove the washer (1).
:Carefully remove the rope rotor
(2) from the starter post
– Remove worn or broken starter
rope, b5.5
452RA002
1
VA
2
Install in the reverse sequence.
– Coat the bore in the rope rotor
with STIHL special lubricant,
b13.
:Fit the rope rotor on the starter
post so that the driver (1) on the
rotor slips behind in the inner
spring loop (2).
452RA003
VA
2
1
Install all other parts in the reverse
sequence.
:Fit the washer and the pawls and
engage the spring clip (1) in the
groove on the starter post (2).
:Make sure the spring clip (1)
engages the guide pegs (arrows)
on the pawls and points them
counterclockwise
452RA001
1
VA
2
Handle the spring clip with care.
The rewind starter may not function
properly if the spring clip is
deformed.
– Tension the rewind spring, b5.8
Install all other parts in the reverse
sequence.
5.4 Rope Rotor
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13BR 500, BR 550, BR 600
– Remove the starter cover with
rewind starter, b5.2
– Remove the rope rotor, b5.4
– Remove the remaining rope from
the rope rotor and starter grip.
:Tie one of the special knots
shown in the end of the new
starter rope.
VA
982RA036
:Thread the new rope through the
top of the starter grip from above.
– Pull the rope with knot into the
starter grip.
212RA307
VA
– Inspect rope guide bushing in the
starter cover for damage and
replace if necessary, b5.6
:Thread the starter rope through
the bushing in the starter cover
from outside.
452RA006
VA
:Thread the rope through the rope
rotor.
– Tie a simple overhand knot in the
end of the rope.
452RA005
VA
:Pull the rope back into the rotor
so that the knot locates in the
recess (arrow).
– Tension the rewind spring, b5.8
Install all other parts in the reverse
sequence.
452RA007
VA
5.5 Starter Rope/Grip
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14 BR 500, BR 550, BR 600
Wear on the guide bushing is
accelerated by the starter rope
being pulled sideways. The wall of
the guide bushing eventually wears
through and the bushing becomes
loose.
– Remove the starter cover with
rewind starter, b5.2
– Remove the rope rotor, b5.4
– Use a suitable tool to pry the
damaged bushing out of the
starter cover.
– Place the new bushing in its seat
in the starter cover.
:Insert the screw spindle (1) of
installing tool 0000 890 2201
through the bushing from inside
the cover.
452RA008
VA
1
– Fit the thrust sleeve (1), tapered
end first, and screw on the hex
nut.
:Tighten down the hex nut until the
bushing is firmly seated.
The installing tool flares the lower
452RA009
VA
1
end of the rope bushing.
– Remove the installing tool.
Install all other parts in the reverse
sequence.
– Troubleshooting, b4.1
Wear face protection and gloves.
– Remove the rope rotor, b5.4
:Use a suitable tool to carefully
remove the rewind spring (1)
from the starter cover (2).
– Remove any pieces of broken
spring from the starter cover,
:With the spring housing facing
452RA010
VA
1
2
you, carefully clip the new rewind
spring into the starter cover,
making sure it is correctly
positioned (arrow).
Install in the reverse sequence.
If the rewind spring pops out and
uncoils during installation, refit it in
special tool 1116 893 4800 as
follows:
5.6 Rope Guide Bushing 5.7 Replacing the Rewind
Spring
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15BR 500, BR 550, BR 600
:Position the outer spring loop at
distance “a” (30 mm) from the
edge of the special tool (1).
452RA011
1
VA
a
:Wind the rewind spring
counterclockwise, from the
outside inwards.
– To simplify this operation, place
the assembly block
1108 893 4800 across the top of
the special tool.
452RA012
VA
:Place the special tool (1) with the
rewind spring on the spring
housing.
The outer spring loop must line up
with the recess in the spring
housing (arrow).
452RA013 VA
1
– Install the rope rotor, b5.4
Install all other parts in the reverse
sequence.
– Remove the starter cover with
rewind starter, b5.2
:Make a loop in the starter rope.
452RA014
VA
:Engage the rope in the notch
(arrow) in the rotor. Grip the rope
close to the rotor and use it to
turn the rotor six full turns
counterclockwise.
452RA168 KN
5.8 Tensioning the Rewind
Spring
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16 BR 500, BR 550, BR 600
:Hold the rope rotor steady.
:Pull out the rope with the starter
grip and straighten it out.
– Hold the starter grip firmly to keep
the rope tensioned.
452RA016
VA
– Let go of the rope rotor and
slowly release the starter grip so
that the rope winds itself onto the
rotor.
The starter grip must sit firmly in the
rope guide bushing without
drooping to one side. If this is not
the case, tension the spring by one
additional turn.
452RA160
VA
When the starter rope is fully
extended, it must still be possible to
rotate the rope rotor at least another
half turn before maximum spring
tension is reached. If this is not the
case, pull the rope out, hold the
rope rotor steady and take off one
turn of the rope.
Do not overtension the rewind
spring as this will cause it to break.
Install in the reverse sequence.
– Remove the starter cover with
rewind starter, b5.2
:Take out the screws (arrows)
452RA024
VA
:Lay the unit on its back.
452RA161
VA
5.9 Shroud
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17BR 500, BR 550, BR 600
:Take out the screws (1).
:Ease the engine in the direction
of the backplate until the stop
buffers (3) are clear of their seats
(arrows) and pull the shroud (2)
towards you at the same
time.rauskommen.
452RA025
3
2
VA
3
11
Install in the reverse sequence.
– Remove the stop buffers (1).
452RA156
1
1
VA
– Coat new stop buffers (1) with
STIHLPressFluidOH723,
b13.
– Use pliers to grip end of stop
buffer and pull it up until its
groove (arrow) engages the
housing.
452RA157
VA
1
BR 500 only
– If the shroud is replaced, also
bond a soundproofing liner (1) in
position.
Install all other parts in the reverse
sequence.
452RA095
VA
1
Dirty air filters reduce engine power,
increase fuel consumption and
make starting more difficult.
The air filter must be replaced when
there is a noticeable loss of engine
power.
:Loosen the screws (arrows).
:Lift away the filter cover (1).
452RA026 VA
1
:Remove the air filter (1).
The filter element cannot be
washed and must be replaced if it is
heavily loaded.
452RA027 VA
1
6. Fuel System
6.1 Air Filter
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18 BR 500, BR 550, BR 600
– If the filter housing has to be
replaced, remove the shroud and
rewind starter, b5.9
:Take out the screws (arrows)
452RA028
VA
:Take out the screw (arrow).
452RA029 VA
:Pull the filter housing (1) off its
mounting (arrow).
– Take the filter housing (1) out of
the machine.
452RA035 VA
1
:Pull off the carburetor (1).
:If necessary, remove the baffle
(2).
When installing, always fit a new
gasket between the carburetor and
filter housing.
452RA030
1
2
VA
:Carefully remove the hoses (1).
:Pull out the throttle cable (2).
Replace damaged hoses.
452RA031
1
VA
1
2
:Carefully pull out the hose (1).
:Carefully disconnect the hose (2)
and pull it out of the housing bore
(arrow).
452RA032
1
VA
2
:Squeeze the tabs (arrows)
together and disengage the fuel
pump (1).
452RA033
1
VA
:Pry the grommet (1) out to the
rear.
Install in the reverse sequence.
452RA034
1
VA
RA_452_00_01_02.book Seite 18 Donnerstag, 16. Februar 2012 11:52 11

19BR 500, BR 550, BR 600
Use a new grommet.
:Push the grommet into the filter
housing from the rear until its
groove (arrow) engages the
housing.
452RA051
VA
:Clip the fuel pump in place so that
the longer stub (1) is at the
bottom.
:Pass the hose (2) that comes
from the tank through the housing
bore (arrow) and push it onto the
long stub (1).
452RA036
1
VA
2
Install all other parts in the reverse
sequence.
– Check tension of throttle cable,
adjust if necessary, b9.3.2
– Troubleshooting, b4.3
In the event of trouble with the
carburetor or fuel supply system,
always check, clean or replace the
tank vent, b6.5
The carburetor can be tested for
leaks with the carburetor and
crankcase tester 1106 850 2905.
– Remove the air filter, b6.1
– Open the tank filler cap to relieve
pressure.
– Close the tank filler cap.
:Disconnect the fuel hose (1) from
the carburetor.
452RA037
VA
1
:Push the hose (1) 1110 141 8600
onto the nipple (2)
0000 855 9200.
VA
143RA172
2 1
:Push the hose (2) with nipple (1)
onto the carburetor’s elbow
connector.
452RA038
VA
2
1
:Connect hose (1) of tester
1106 850 2905 to the nipple (2).
452RA162
VA
2
1
6.2 Carburetor
6.2.1 Leakage Test
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