Stihl MM 55 User manual

Instruction Manual
Notice d’emploi
STIH)
STIHL MM 55
BA_U1_82_01.fm Seite 0 Montag, 3. Juli 2006 2:21 14

1MM 55
English
BA_SE_130_004_01_05.fmPrinted on chlorine-free paper.
Printing inks contain vegetable oils; paper can be recycled.
© ANDREAS STIHL AG & Co. KG, 2006 0458 469 8221 A. M0,5. G6. PM. Printed in USA
STIHl
Contents
MultiSystem ...................................... 2
Guide to Using this Manual .............. 2
Safety Precautions and
Working Techniques ......................... 3
Authorized MultiTools ..................... 12
Adjusting the bike handle ............... 12
Fuel ................................................ 12
Fueling ............................................ 13
Starting / Stopping the Engine ........ 14
Extra Weight ................................... 16
Wheels ........................................... 17
Operating Instructions .................... 18
Replacing the Air Filter ................... 18
Motor Management ........................ 19
Adjusting the carburetor ................. 19
Checking the Spark Plug ................ 21
Rewind Starter ................................ 22
Storage ........................................... 22
Inspections and Maintenance
by STIHL Service ........................... 23
Maintenance Chart ......................... 24
Main components ........................... 25
Specifications ................................. 27
Special accessories ........................ 27
Maintenance and Repairs ............... 28
STIHL Limited Emission Control
Warranty Statement ........................ 29
Ensure that your power tool is only used
by persons who have read the User
Manuals for the MultiEngine and
MultiTool.
The maintenance and safety
instructions from page 3 onwards must
be read by the operator and understood
before using the power tool in order to
obtain maximum performance and
satisfaction from your STIHL power tool.
Consult your STIHL dealer or the STIHL
distributor responsible for your area if
you do not understand any of the
instructions in the two manuals.

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MM 55
Important!
A number of special safety precautions
must be observed in order to reduce the
risk of injury due to the high-speed tool
used in this power tool. Negligence or
incorrect use can cause serious or even
fatal injuries.
It is the philosophy of STIHL to
constantly improve all our products.
Design changes and improvements may
therefore frequently be implemented.
The data and illustrations contained in
this manual consequently may change.
Please contact your STIHL dealer for
information and advice if the operating
properties or appearance of your power
tool differ from those described in the
two manuals.
In the STIHL MultiSystem the
MultiEngine can be combined with a
number of different MultiTools to
produce a power tool. In this instruction
manual the functional unit formed by the
MultiEngine and MultiTool is referred to
as the power tool.
The MultiEngine and MultiTool come
with separate instruction manuals.
Always read and make sure you
understand both instruction manuals
before starting and using your machine.
Keep the manuals in a safe place for
later reference.
Pictograms
All the pictograms attached to the
machine are shown and explained in
this manual.
The operating and handling instructions
are supported by illustrations.
Symbols in text
The individual steps or procedures
described in the manual may be marked
in different ways:
:A bullet marks a step or procedure
without direct reference to an
illustration.
A description of a step or procedure that
refers directly to an illustration may
contain item numbers that appear in the
illustration.
Example:
Loosen the screw (1)
Lever (2) ...
MultiSystem
469BA028 KN
+
+
Guide to Using this Manual

3MM 55
English
In addition to the operating instructions,
this manual may contain paragraphs
that require your special attention. Such
paragraphs are marked with the
symbols described below:
Warning where there is a risk of an
accident or personal injury or
serious damage to property.
Caution where there is a risk of
damaging the machine or its
individual components.
Note or hint which is not essential
for using the machine, but may
improve the operator’s under-
standing of the situation and result
in better use of the machine.
Note or hint on correct procedure in
order to avoid damage to the
environment.
Equipment and features
This instruction manual may refer to
several models with different
features. Components that are not
installed on all models and related
applications are marked with an
asterisk (*). Such components may
be available as special accessories
from your STIHL dealer.
Engineering improvements
STIHL’s philosophy is to continually
improve all of its products. As a result,
engineering changes and improvements
are made from time to time. If the
operating characteristics or the
appearance of your machine differ from
those described in this manual, please
contact your STIHL dealer for
assistance.
Therefore some changes, modifications
and improvements may not be covered
in this manual.
Warning!
Because this MultiEngine
is a high-speed power
tool, special safety
precautions must be
observed to reduce the
risk of personal injury.
It is important that you
read, fully understand and
observe the following
safety precautions and
warnings. Read the
owner's manuals and the
safety instructions of your MultiEngine
and MultiTool periodically. Careless or
improper use of any power tool may
cause serious or fatal injury.
Have your STIHL dealer show you how
to operate your power tool. Observe all
applicable local safety regulations,
standards and ordinances.
!Warning!
Do not lend or rent your power tool
without the owner's manuals. Be sure
that anyone using your power tool
understands the information contained
in these manuals.
Safety Precautions and
Working Techniques

4
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MM 55
!Warning!
Minors should never be allowed to use a
power tool. Bystanders, especially
children, and animals should not be
allowed in the area where a power tool is
in use.
Never let the power tool run unattended.
Most of these safety precautions and
warnings apply to the use of all STIHL
power tools. Different models may have
different parts and controls. See the
appropriate section of your owner's
manual for a description of the controls
and function of the parts of your power
tool model.
Safe use of a power tool involves
1. the operator
2. the power tool
3. the use of the power tool.
THE OPERATOR!
Physical Condition
You must be in good physical condition
and mental health and not under the
influence of any substance (drugs,
alcohol, etc.) which might impair vision,
dexterity or judgement. Do not operate a
power tool when you are fatigued.
Be alert - if you get tired while operating
your power tool, take a break. Tiredness
may result in loss of control. Working
with any power tool can be strenuous. If
you have any condition that might be
aggravated by strenuous work, check
with your doctor before operating a
power tool.
!Warning!
The ignition system of the STIHL unit
produces an electromagnetic field of
very low intensity. This field may
interfere with some pacemakers. To
reduce the risk of serious or fatal injury,
persons with a pacemaker should
consult their physician and the
pacemaker manufacturer before
operating this tool.
Proper Clothing
!Warning!
To reduce the risk of injury, the operator
should wear proper protective apparel.
!Warning!
To reduce the risk of injury
to your eyes never
operate a power tool
unless wearing goggles or
properly fitted safety
glasses with adequate top
and side protection complying with ANSI
Z 87.1 (or your applicable national
standard).
!Warning!
MultiEngine noise may
damage your hearing.
Wear sound barriers (ear
plugs or ear mufflers) to
protect your hearing.
Continual and regular
users should have their hearing checked
regularly.
For further instructions on proper
clothing see the Safety Instructions in
the owner’s manual of the MultiTool.

5MM 55
English
THE POWER TOOL
For illustrations and definitions of the
power tool parts see the chapter on
"Parts and Controls".
!Warning!
Never modify a power tool in any way.
Only MultiTools supplied by STIHL or
expressly approved by STIHL for use
with the specific STIHL MultiEngine
models are authorized. Although certain
unauthorized MultiTools may be useable
on the STIHL MultiEngine, their use may
in fact be extremely dangerous.
THE USE OF THE POWER TOOL
Transporting the power tool
!Warning!
Always turn off the engine and make
sure the working tool has stopped before
putting a power tool down. When
transporting your power tool in a vehicle,
properly secure it to prevent turnover,
fuel spillage and damage to the power
tool.
Preparation for the use of the power
tool
Always check your power tool for proper
condition and operation before starting,
particularly the throttle trigger, starting
throttle lock, slide control, working tool
and deflector.
Before starting work, open up the bike
handle and lock it in position with the
rotary knob. See chapter on "Adjusting
Bike Handle".
The throttle trigger must move freely and
always spring back to the idle position.
The working tool must be properly
tightened and in safe operating
condition. Inspect for loose parts (nuts,
screws, etc.) and for cracked, bent,
warped or damaged working tools.
Fueling
Your STIHL power tool uses an oil-
gasoline mixture for fuel (see the
chapter on "Fuel" in your owner’s
manual).
!Warning!
Gasoline is an extremely
flammable fuel. If spilled
and ignited by a spark or
other ignition source, it
can cause fire and serious
burn injury or property
damage. Use extreme caution when
handling gasoline or fuel mix.
Do not smoke or bring any fire, flame,
spark or any other ignition source near
the fuel or power tool.
Fueling Instructions
!Warning!
Fuel your power tool in well-ventilated
areas, outdoors. Always shut off the
engine and allow it to cool before
refueling. Gasoline vapor pressure may
build up inside the fuel tank depending
on the fuel used, the weather conditions
and the tank venting system.

6
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MM 55
In order to reduce the risk of burns and
other personal injury from escaping gas
vapor and fumes, remove the fuel filler
cap on your power tool slowly and
carefully so as to allow any pressure
build-up in the tank to release slowly.
Never remove fuel filler cap while engine
is running.
!Warning!
To reduce the risk of fire or burn injury,
let the unit cool down before refueling
your power tool after use.
Select bare ground for fueling and move
at least 10 feet (3 m) from the fueling
spot before starting the engine. Wipe off
any spilled fuel before starting your
power tool and check for leakage.
!Warning!
Check for fuel leakage while refueling
and during operation. If fuel leakage is
found, do not start or run the engine until
the leak is fixed and spilled fuel has
been wiped away. Take care not to get
fuel on your clothing. If this happens,
change your clothing immediately.
Different models may be equipped with
different fuel caps.
Cap with Grip
!Warning!
In order to reduce the risk of fuel spillage
and fire from an improperly tightened
fuel cap, correctly position and tighten
the fuel cap in the fuel tank opening.
To do this with this STIHL
cap, raise the grip on the
top of the cap until it is
upright at a 90° angle.
Insert the cap in the fuel
tank opening with the
triangular marks on the grip of the cap
and on the fuel tank opening lining up.
Using the grip, turn the cap firmly
clockwise as far as it will go (approx. a
quarter turn).
Fold the grip flush with the
top of the cap. If the grip
does not lie completely
flush with the cap and the
detent on the grip does
not fit in the
corresponding recess in the filler neck,
the cap is not properly seated and
tightened and you must repeat the
above steps.
Screw-on Cap
!Warning!
Unit vibrations can cause
an improperly tightened
fuel filler cap to loosen or
come off and spill
quantities of fuel. In order
to reduce the risk of fuel
spillage and fire, tighten the fuel filler cap
by hand with as much force as possible.
Operating instructions
!Warning!
Improper use of any power tool can
cause serious or fatal personal injury. To
reduce the risk of personal injury to the
operator from operating the power tool
always follow the safety instructions on
operating the power tool as provided in
the owner’s manuals of the MultiEngine
and the MultiTool.
Before Starting
Always check your power tool for proper
condition and operation before starting –
refer to appropriate sections in the
instruction manuals.

7MM 55
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!Warning!
To reduce risk of injury from MultiTool
rotating in the wrong direction, check
that the position of the gearbox is correct
and change it if necessary.
On metal tools (top illustration), position
the gearbox so that the shaft is below
the drive tube.
On sweeping tools (bottom illustration),
position the gearbox so that the shaft is
above the drive tube.
Shaft (1) below the drive tube.
Use position 1 for:
- BF-MM pick tines
- BK-MM bolo tines
- FC-MM edger
- RL-MM aerator
- MF-MM dethatcher
Shaft (2) above the drive tube
Use position 2 for:
- KB-MM bristle brush
- KW-MM STIHL PowerSweepTM
Check the owner´s manual for the
MultiTool to ensure you are using the
appropriate deflector for that MultiTool.
Starting
!Warning!
Your power tool is a one-person
machine. To reduce the risk of injury,
keep bystanders out of your working
area (see MultiTool manuals for specific
distances).
Stop the engine and cutting tool
immediately if you are approached. Start
and operate your power tool without
assistance. For specific starting
instructions, see the appropriate section
of your manuals.
Place the unit on firm ground in an open
area. The attachments must be clear of
the ground and all other obstructions.
!Warning!
When starting, make sure you have a
firm footing - as shown; always stand to
one side of the machine to avoid risk of
injury from contact with rotating tool.
469BA026 KN
1
2
469BA027 KN

8
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!Warning!
To reduce the risk of injury
from loss of control, be
absolutely sure that the
working tool is clear of
you and all other
obstructions and objects,
including the ground, because when the
engine starts at starting-throttle, engine
speed will be fast enough for the clutch
to engage and move the working tool.
!Warning!
When you pull the starter grip, don't
wrap the starter rope around your hand.
Do not allow the grip to snap back, but
guide the starter rope to rewind it
properly. Failure to follow this procedure
may result in injury to hand or fingers
and may damage the starter
mechanism.
See also the safety instructions on
starting in the owner’s manual of the
MultiTool.
Holding and Controlling the
Power Tool
Always hold the power tool firmly with
both hands - as shown. Wrap your
fingers tightly around the handles,
keeping the handles cradled between
your thumb and forefinger. Keep your
hands in this position to have your power
tool under control at all times. Make sure
the handles and grips are in good
condition and free of moisture, pitch, oil
or grease.
Muffler
!Warning!
Do not operate your power tool if the
muffler is damaged, missing or modified.
Such a muffler could cause an increase
in heat radiation or sparks, thereby
increasing the risk of fire or burn injury.
You may also damage the engine
permanently.
!Warning!
The muffler and other parts of the engine
(e.g. fins of the cylinder, spark plug)
become hot during operation and remain
hot for a while after stopping the engine.
To reduce risk of burns do not touch the
muffler and other parts while they are
hot.
!Warning!
To reduce the risk of fire or burn injury,
keep the area around the muffler clean.
Remove all debris such as pine needles,
branches or leaves when the engine is
shut off and has cooled.
469BA045 KN

9MM 55
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Catalytic converter
!Warning!
Some STIHL power tool
models are equipped with
a catalytic converter,
which is designed to
reduce the exhaust
emissions of the engine
by a chemical process in the muffler.
Due to this process, the muffler does not
cool down as rapidly as conventional
mufflers when the engine returns to idle
or is shut off. To reduce the risk of fire
and burn injuries, the following specific
safety precautions must be observed.
!Warning!
Since a muffler with a catalytic converter
cools down less rapidly than conven-
tional mufflers, never set your power tool
down where the muffler is near dry
brush, grass, wood chips or other
combustible materials while it is still hot.
Let the engine cool down sitting in the
upright position on concrete, metal, bare
ground or solid wood away from any
combustible substances.
!Warning!
An improperly mounted or damaged
cylinder housing or a damaged/
deformed muffler shell may interfere
with the cooling effect of the catalytic
converter. To reduce the risk of fire or
burn injury, do not continue working with
a damaged or improperly mounted
cylinder housing or a damaged/
deformed muffler shell. Your catalytic
converter is furnished with screens
designed to reduce the risk of fire from
the emission of hot particles. Due to the
heat from the catalytic reaction, these
screens will normally stay clean and
need no service or maintenance. If you
experience loss of performance and you
suspect a clogged screen, have your
muffler maintained by a STIHL Servicing
Dealer.
Working Conditions
Operate and start your power tool only
outdoors in a ventilated area.
Operate the power tool under good
visibility and daylight conditions only.
Work carefully.
!Warning!
Your power tool produces
toxic exhaust fumes as
soon as the engine is
running. These gases
(e.g. carbon monoxide)
may be colorless and
odorless. To reduce the risk of serious or
fatal injury from inhaling toxic fumes,
never run the power tool indoors or in
poorly ventilated locations.
!Warning!
Use of this product can generate dust
and fumes containing chemicals known
to cause respiratory disease, cancer,
birth defects, or other reproductive
harm. If you are unfamiliar with the risks
associated with the particular dust or
fume at issue, consult your employer,
governmental agencies such as OSHA
and NIOSH and other sources on
hazardous materials. The State of
California and some other authorities,
for instance, have published lists of
substances known to cause cancer,
reproductive toxicity, etc.

10
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Control dust and fumes at the source
where possible. In this regard use good
work practices and follow the
recommendations of OSHA/NIOSH and
occupational and trade associations.
When the inhalation of toxic dust and
fumes cannot be eliminated, the
operator and any bystanders should
always wear a respirator approved by
NIOSH/MSHA for the type of dust and /
or fumes encountered.
Important adjustments
!Warning!
To reduce the risk of personal injury from
loss of control or contact with the
running working tool, do not use a power
tool with incorrect idle adjustment. At
correct idle speed, the working tool
should not move. For directions on how
to adjust idle speed, see the appropriate
section of your owner's manual. If you
cannot set the correct idle speed, have
your STIHL dealer check your power
tool and make proper adjustments and
repairs.
MAINTENANCE, REPAIR AND
STORING
Maintenance, replacement, or repair
of the emission control devices and
systems may be performed by any
nonroad engine repair establishment
or individual. However, if you claim
warranty coverage for a component
which has not been serviced or
maintained properly or if
nonapproved replacement parts were
used, STIHL may deny warranty
coverage.
!Warning!
Use only genuine STIHL replacement
parts for maintenance and repair. Use of
non-STIHL parts may increase the risk
of serious or fatal injury.
Follow the maintenance and repair
instructions in the appropriate section of
your owner's manual. Please refer to the
maintenance chart on the last pages of
this manual.
!Warning!
Always stop the engine and make sure
that the working tool is stopped before
doing any maintenance or repair work or
cleaning the power tool. Do not attempt
any maintenance or repair work not
described in your owner's manual. Have
such work performed at your STIHL
service shop only.
Wear gloves when handling or
performing maintenance on any blade.
!Warning!
Never repair damaged working tools by
welding, straightening or modifying the
shape. This may cause parts of the
working tool to come off and result in
serious or fatal injuries.

11MM 55
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!Warning!
To reduce the risk of fire and burn
injuries, check the fuel filler cap for leaks
at regular intervals. Use the specified
spark plug and make sure it and the
ignition lead are always clean and in
good condition. Always press spark plug
boot snugly onto spark plug terminal of
the proper size. (Note: If terminal has a
detachable SAE adapter nut, it must be
properly attached.) A loose connection
between spark plug boot and ignition
wire connector in the boot may create
arcing that could ignite combustible
fumes and cause a fire.
!Warning!
Never test the ignition system with
ignition wire boot removed from the
spark plug or with a removed spark plug,
since uncontained sparking may cause
a fire.
!Warning!
A damaged or improperly maintained
muffler will increase the risk of fire and
hearing loss. Never touch a hot muffler
or burn will result. If your muffler was
equipped with a spark-arresting screen
to reduce the risk of fire (e.g. in the USA,
Canada and Australia), never operate
your Engine if the screen is missing or
damaged. Do not disassemble, modify
or remove any part of the muffler or
spark arresting screen. Remember that
the risk of forest fires is greater in hot
and dry weather. Have your muffler
serviced and repaired by your STIHL
Servicing Dealer only.
Keep the cutting attachment sharp.
Tighten all nuts, bolts and screws,
except the carburetor adjustment
screws, after each use.
Additionally, the daily maintenance
schedule for your power tool set forth in
your STIHL Owner's Manual should be
strictly followed.
For any maintenance please refer to the
maintenance chart and to the warranty
statement near the end of this manual.
Store the power tool in a dry, high locked
location out of reach of children.
Before storing for longer than a few
days, always empty the fuel tank. See
chapter “Storing the machine“.

12
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MM 55
The following STIHL MultiTools may be
mounted on the MultiEngine:
:Turn knob (1)
:Unfold bike handle as far as
possible into working position
:Retighten knob
This engine is certified to operate on
unleaded gasoline and with the mix ratio
50:1.
Your engine requires a mixture of high-
quality premium gasoline and high-
quality two-stroke air-cooled engine oil.
Use premium branded unleaded
gasoline with a minimum octane rating
of 89 RON.
Note: Models equipped with a catalytic
converter require unleaded gasoline. A
few tankfuls of leaded gasoline can
reduce the efficiency of the catalytic
converter by more than 50%.
Fuel with a lower octane rating may
result in preignition (causing "pinging")
which is accompanied by an increase in
engine temperature. This, in turn,
increases the risk of the piston seizure
and damage to the engine.
The chemical composition of the fuel is
also important. Some fuel additives not
only detrimentally affect elastomers
(carburetor diaphragms, oil seals, fuel
lines etc.), but magnesium castings as
well. This could cause running problems
or even damage the engine. For this
reason it is essential that you use only
high-quality fuels!
MultiTool Use
BF-MM Pick tines
BK-MM Bolo tines
RL-MM Aerator
FC-MM Edger
MF-MM Dethatcher
KW-MM STIHL PowerSweepTM
KB-MM Bristle brush
Authorized MultiTools
469BA025 KN
BF-MM
BK-MM
RL-MM
FC-MM
KB-MMKW-MM
MF-MM
Adjusting the bike handle
1
469BA007 KN
Fuel

13MM 55
English
Fuels with different percentages of
ethanol are being offered. Ethanol can
affect the running behaviour of the
engine and increase the risk of lean
seizure.
Use only STIHL two-stroke engine oil or
equivalent high-quality two-stroke air-
cooled engine oils for mixing.
We recommend STIHL 50:1 two-stroke
engine oil since it is specially formulated
for use in STIHL engines.
Do not use BIA or TCW (two-stroke
water cooled) mix oils!
Use only STIHL 50:1 heavy-duty
engine oil or an equivalent quality two-
stroke engine oil for the fuel mix in
models equipped with a catalytic
converter.
Take care when handling gasoline.
Avoid direct contact with the skin and
avoid inhaling fuel vapour.
The canister should be kept tightly
closed in order to avoid any moisture
getting into the mixture.
The fuel tank and the canister in which
fuel mix is stored should be cleaned
from time to time.
Fuel mix ratio
Only mix sufficient fuel for a few days
work, not to exceed 3 months of storage.
Store in approved safety fuel-canisters
only. When mixing, pour oil into the
canister first, and then add gasoline.
Examples
Dispose of empty mixing-oil canisters
only at authorized disposal locations.
Before fueling, clean the filler cap and
the area around it to ensure that no dirt
falls into the tank.
Always thoroughly shake the mixture in
the canister before fueling your
machine.
In order to reduce the risk of burns
or other personal injury from
escaping gas vapor and fumes,
remove the fuel filler cap carefully
so as to allow any pressure build-up
in the tank to release slowly.
After fueling, tighten fuel cap as
securely as possible by hand.
Gasoline Oil (STIHL 50:1 or
equivalent high-quality
oils)
liters liters (ml)
10.02(20)
5 0.10 (100)
10 0.20 (200)
15 0.30 (300)
20 0.40 (400)
25 0.50 (500)
Fueling
232BA046 KN

14
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MM 55
Controls
:Throttle trigger interlock (1), throttle
trigger (2) and slide control (3) with
positions:
:START (4),
:#– normal run position (5) and
:O – STOP (6); to stop engine:
push slide control in direction of
arrow to stop symbol ( h ) (7).
Starting
:Move bike handle into working
position
:Hold down the throttle trigger
interlock and squeeze the throttle
trigger.
:While holding both levers in this
position, move slide control to
START and hold it there.
:Now release the throttle trigger,
slide control and throttle trigger
interlock in that order. This is the
starting throttle position.
:Set the choke lever (8):
For cold start to g
For warm start to e
– also use this position if the engine
has been running but is still cold.
:Press the fuel pump bulb (9) at least
five times – even if the bulb is
already filled with fuel
Starting / Stopping
the Engine
1
4
56
73
START
2
STOP
002BA036 KN
8
469BA033 KN
9

15MM 55
English
:Retract wheels, if fitted
:Put the unit on the ground:
It must rest securely on the engine
flange and on the support on the
frame.
:Check that the MultiTool is not
touching the ground or any other
obstacles – refer also to "Starting /
Stopping the Engine" in the
instruction manual of the MultiTool
you are using.
:Make sure you have good balance
and secure footing – as shown in
the illustration. To reduce the risk of
injury from contact with rotating
attachments, always stand to the
side of the power tool.
:With your left hand on the loop
handle, press the unit firmly against
the ground.
Do not stand or kneel on the
handlebar!
:Pull the starter grip slowly with your
right hand until you feel it engage –
then give it a brisk strong pull.
Do not pull out the starter rope
completely –
it might break.
:Do not let the starter grip snap
back – guide it slowly into the
housing so that the starter rope can
rewind properly
:Continue cranking until the engine
begins to fire. After no more than
five pulls, move the choke lever (8)
to the e position
:Continue cranking.
As soon as the engine runs:
:Blip the throttle trigger –
the engine returns to idling speed
Make sure carburetor is correctly
adjusted – tool must not move when
engine is idling!
Your unit is now ready for operation.
To shut down the engine:
:Move the slide control in the
direction of the arrow ( h) to
STOP – $
469BA005 KN
469BA004 KN
469BA006 KN
8
469BA034 KN

16
English
MM 55
If the engine does not start:
Choke lever
If you did not move the choke lever to e
quickly enough after the engine began to
fire, the combustion chamber has
flooded.
:Set the choke lever to e
:Move slide control, interlock lever
and throttle trigger to starting throttle
position.
:Start the engine by pulling the
starter rope firmly. 10 to 20 pulls
may be necessary.
If the engine still does not start:
:Move slide control to STOP.
:Pull off the spark plug boot (10).
:Unscrew and dry off the spark plug
:Open the throttle wide.
:Pull the starter rope several times to
clear the combustion chamber.
:Refit the spark plug.
:Connect the spark plug boot (press
it down firmly).
:Move slide control to #
:Set the choke lever to e– even if
the engine is cold.
:Now start the engine.
Fuel tank run until dry
:After refuelling, press fuel pump
bulb at least five times – even if the
bulb is already filled with fuel.
:Set the choke lever according to
engine temperature.
:Now start the engine.
An extra weight (special accessory) may
be retrofitted on the MultiEngine to
increase the weight on the MultiTool.
Only an original STIHL extra weight may
be used. Other weights may cause
damage to the unit and physical injury.
Mounting the extra weight
Unscrew weights on the side without
square end – as follows:
:Unscrew and remove the outer
weight.
:Unscrew inner weight and remove
from the bolt.
:Slide the extra weight (1) with bolt
through the bore (2) in the flange,
turning it until the square engages
the recess in the flange.
:Screw weight onto the bolt and
tighten it down firmly.
:Fit and tighten down the outer
weight firmly.
10
232BA048 KN
Extra Weight
2
469BA041 KN
1

17MM 55
English
Use the combination wrench to unscrew
and retighten the weights.
One or two weights can be mounted
on each side of the extra weight as
required. Extra weight: 4 kg (8.8 lb)
and 2 kg (4.4 lb).
The maximum allowable extra
weight is 4 kg (8.8 lb). Never use a
heavier extra weight, as this may
damage the unit.
The MultiEngine can be equipped with a
set of wheels (special accessory) for
greater mobility. Use only original STIHL
wheels since the use of other wheels
may result in damage to the machine
and personal injury.
Mounting the wheels
Turn the power tool on its back so
that it rests on the handles.
:Fit the two sleeves (1) in the frame.
:Push the frame onto the flange.
:Insert the screw (2) with washer (3)
through the hole (4) in the flange.
:Fit the washer (3) and nut (5) and
tighten down firmly.
:Insert screws (7) in tapped holes in
frame, push the the notched
adjuster rail (6) towards the handles
while tightening down the screws.
:The wheels must swing down under
their own weight when the machine
is in the normal working position. If
necessary, loosen the nut (5) a
quarter turn.
Wheels
3
6
469BA035 KN
241
7
7
5
31

18
English
MM 55
Extending or retracting wheels
The wheels can be locked in different
positions.
The wheels can be retracted if they are
not required.
:Loosen the rotary knob (8).
:Engage rotary knob in required
position and tighten it down firmly.
During break-in period
A factory new machine should not be run
at high revs (full throttle off load) for the
first three tank fillings. This avoids
unnecessary high loads during the
break-in period. As all moving parts
have to bed in during the break-in
period, the frictional resistances in the
engine are greater during this period.
The engine develops its maximum
power after about 5 to 15 tank fillings.
During operation
After a long period of full-throttle
operation, allow engine to run for a while
at idle speed so that the heat in the
engine can be dissipated by flow of
cooling air. This protects engine-
mounted components (ignition,
carburetor) from thermal overload.
After finishing work
Storing for short period:
Wait for engine to cool down. To avoid
condensation, fill the fuel tank and keep
the unit in a dry place until you need it
again. Storing for a long period:
see chapter "Storing the Machine".
Dirty air filters reduce engine power,
increase fuel consumption and make
starting more difficult.
If there is a noticeable loss of engine
power:
:Set the choke lever to g
:Loosen the screw (1) and remove
the filter cover (2).
:Clean away loose dirt from inside
the cover and around the filter.
8
469BA036 KN
Operating Instructions Replacing the Air Filter
1
469BA037 KN
2

19MM 55
English
:Remove the filter element (3) and
check it – if it is dirty or damaged, fit
a new element.
Always replace damaged parts.
:Fit the filter element (3) in the filter
housing (4).
:Fit the filter cover and tighten it
down firmly.
Exhaust emissions are controlled by the
design of the fundamental engine
parameters and components (e.g.
carburation, ignition, timing and valve or
port timing) without the addition of any
major hardware.
The carburetor is set to the basic setting
at the factory.
This carburetor setting ensures that an
optimum fuel-air mixture is delivered to
the engine under all operating
conditions.
With this carburetor, the setting can only
be adjusted within limits via the high
speed adjusting screw.
469BA038 KN
3
4
Motor Management Adjusting the carburetor