Stihl Km 55 R Manual

							{
STIHL KM 55 R
Warning!
Read and follow all safety 
precautions in Instruction Manual – 
improper use can cause serious or 
fatal injury.
Advertencia!
Lea y siga todas las precauciones 
de seguridad dadas en el manual 
de instrucciones – el uso incorrecto 
puede causar lesiones graves o 
mortales.
Instruction Manual
Manual de instrucciones 
						

							Instruction Manual
1 - 29
Manual de 
instrucciones
31 - 63 
						

							Original Instruction Manual Printed on chlorine-free paper
Printing inks contain vegetable oils, paper can be recycled. © ANDREAS STIHL AG & Co. KG, 2011
0458-461-8621-A. M9.A11.PM. 
0000001986_003_GB
KM 55 R, KM 55 RCEnglish
1
{
Contents
Allow only persons who fully understand 
the manuals of the KombiEngine and the 
KombiTool to operate this power tool 
combination.
To receive maximum performance and 
satisfaction from your STIHL power tool, 
it is important that you read, understand 
and follow the safety precautions and 
the operating and maintenance 
instructions in chapter Safety 
Precautions and Working Techniques 
before using your power tool. For further 
information you can go to 
www.stihlusa.com.
Contact your STIHL dealer or the STIHL 
distributor for your area if you do not 
understand any of the instructions in the 
two manuals. KombiSystem 2
Guide to Using this Manual 2
Safety Precautions and Working 
Techniques 3
Approved KombiTools 10
Mounting the Loop Handle 11
Fuel 12
Fueling 13
Starting / Stopping the Engine 13
Operating Instructions 15
Cleaning the Air Filter 16
Engine Management 16
Adjusting the Carburetor 17
Spark Plug 18
Engine Running Behavior 19
Rewind Starter 20
Storing the Machine 20
Inspections and Maintenance by 
Dealer 20
Maintenance and Care 21
Main Parts 22
Specifications 23
Special Accessories 24
Maintenance and Repairs 24
STIHL Incorporated Federal 
Emission Control Warranty 
Statement 25
STIHL Incorporated California 
Exhaust and Evaporative 
Emissions Control Warranty 
Statement 27
Trademarks 29Warning!
Because this KombiEngine is the 
engine for a high-speed power tool, 
some special safety precautions must 
be observed to reduce the risk of per-
sonal injury. Careless or improper use 
may cause serious or even fatal injury. 
						

							KM 55 R, KM 55 RC English
2 In the STIHL KombiSystem a number of 
different KombiEngines and KombiTools 
can be combined to produce a power 
tool. In this instruction manual the 
functional unit formed by the 
KombiEngine and KombiTools is 
referred to as the power tool.
Therefore, the separate instruction 
manuals for the KombiEngine and 
KombiTool should be used together for 
the power tool.
Always read and and make sure you 
understand both instruction manuals 
before using your power tool for the first 
time and keep them in a safe place for 
future reference.
Pictograms
All the pictograms attached to or 
embossed on the machine are shown 
and explained in this manual.
Symbols in Text
Many operating and safety instructions 
are supported by illustrations.
The individual steps or procedures 
described in the manual may be marked 
in different ways:
NA bullet marks a step or procedure.
A description of a step or procedure that 
refers directly to an illustration may 
contain item numbers that appear in the 
illustration. Example:
NLoosen the screw (1).
NLever (2) ...
In addition to the operating instructions, 
this manual may contain paragraphs 
that require your special attention. Such 
paragraphs are marked with the 
symbols and signal words described 
below:
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. Therefore, 
some changes, modifications and 
improvements may not be covered in 
this manual. If the operating 
characteristics or the appearance of 
your machine differ from those 
described in this manual, please contact 
your STIHL dealer for assistance.
KombiSystem
.
.
.
.
002BA442 KN
+
+
Guide to Using this Manual
Danger!
Indicates an imminent risk of severe or 
fatal injury.
Warning!
Indicates a hazardous situation which, if 
not avoided, could result in severe or 
fatal injury.
Caution!
Indicates a risk of property damage, 
including damage to the machine or its 
individual components. 
						

							KM 55 R, KM 55 RCEnglish
3 Have your STIHL dealer show you how 
to operate your power tool. Observe all 
applicable local safety regulations, 
standards and ordinances.
Use your power tool only for the 
applications described in the instruction 
manual of the KombiTool you are using.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 
KombiEngine and KombiTool instruction 
manuals for a description of the controls 
and the function of the parts of your 
model.
Do not clean your machine with a 
pressure washer. The solid jet of water 
may damage parts of the machine.
Safe use of a KombiEngine 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 judgment. Do not operate 
this machine when you are fatigued.
These conditions reduce the hands 
ability to feel and regulate temperature, 
produce numbness and burning 
sensations and may cause nerve and 
circulation damage and tissue necrosis.
All factors which contribute to 
whitefinger disease are not known, but 
cold weather, smoking and diseases or 
physical conditions that affect blood 
vessels and blood transport, as well as 
high vibration levels and long periods of 
exposure to vibration are mentioned as 
factors in the development of whitefinger Safety Precautions and 
Working Techniques
Because this KombiEn-
gine is the engine for a 
high-speed power tool, 
special safety precau-
tions must be observed to 
reduce the risk of per-
sonal injury.
It is important that you 
read, fully understand 
and observe the following 
safety precautions and 
warnings. Read the 
instruction manuals and 
the safety precautions of 
your KombiEngine and 
KombiTool periodically. 
Careless or improper use 
may cause serious or 
fatal injury.
Warning!
Do not lend or rent your power tool with-
out the instruction manuals. Be sure that 
anyone using it understands the infor-
mation contained in these manuals.
Warning!
Do not use it for other purposes, since 
misuse may result in personal injury or 
property damage, including damage to 
the machine.
Warning!
Minors should never be allowed to use 
this power tool. Bystanders, especially 
children, and animals should not be 
allowed in the area where it is in use.
Warning!
To reduce the risk of injury to bystand-
ers and damage to property, never let 
your power tool run unattended. When it 
is not in use (e.g. during a work break), 
shut it off and make sure that unauthor-
ized persons do not use it.
Warning!
Be alert – if you get tired, 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 this machine.
Warning!
Prolonged use of a power tool (or other 
machines) exposing the operator to 
vibrations may produce whitefinger dis-
ease (Raynauds phenomenon) or 
carpal tunnel syndrome. 
						

							KM 55 R, KM 55 RC English
4 disease. In order to reduce the risk of 
whitefinger disease and carpal tunnel 
syndrome, please note the following:
–Most STIHL power tools are 
available with an anti-vibration 
(AV) system designed to reduce 
the transmission of vibrations 
created by the machine to the 
operators hands. An AV system is 
recommended for those persons 
using power tools on a regular or 
sustained basis.
–Wear gloves – not while using 
KombiTool BG-KM – and keep your 
hands warm.
–Keep the AV system well 
maintained. A power tool with loose 
components or with damaged or 
worn AV elements will tend to have 
higher vibration levels.
–Maintain a firm grip at all times, but 
do not squeeze the handles with 
constant, excessive pressure. Take 
frequent breaks.
All the above-mentioned precautions do 
not guarantee that you will not sustain 
whitefinger disease or carpal tunnel 
syndrome. Therefore, continual and 
regular users should closely monitor the 
condition of their hands and fingers. If 
any of the above symptoms appear, 
seek medical advice immediately.
Proper Clothing
Be particularly alert and cautious when 
wearing hearing protection because 
your ability to hear warnings (shouts, 
alarms, etc.) is restricted.
For further instructions on proper 
clothing see the safety precautions in 
the instruction manual of the KombiTool 
you are using.
THE POWER TOOL
For illustrations and definitions of the 
power tool parts see the chapter on 
Main Parts and Controls.
If this tool is subjected to unusually high 
loads for which it was not designed (e.g. 
heavy impact or a fall), always check 
that it is in good condition before 
continuing work. Check in particular that 
the fuel system is tight (no leaks) and 
that the controls and safety devices are 
working properly. Do not continue 
operating this machine if it is damaged. 
In case of doubt, have it checked by your 
STIHL servicing dealer.
THE USE OF THE POWER TOOL
Transporting the Power Tool Warning!
The ignition system of the STIHL unit 
produces an electromagnetic field of a 
very low intensity. This field may inter-
fere with some pacemakers. To reduce 
the risk of serious or fatal injury, persons 
with a pacemaker should consult their 
physician and the pacemaker manufac-
turer before operating this tool.
Warning!
To reduce the risk of injury, the operator 
should wear proper protective apparel.
Warning!
Power tool 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.
Warning!
Never modify this power tool in any way. 
Only attachments supplied by STIHL or 
expressly approved by STIHL for use 
with the specific STIHL KombiEngine 
model are authorized. Although certain 
unauthorized attachments are useable 
with STIHL power tools, their use may, 
in fact, be extremely dangerous.
Warning!
Always switch off the engine and make 
sure the working tool has stopped 
before putting a power tool down. When 
transporting your power tool in a vehi-
cle, properly secure it to prevent 
turnover, fuel spillage and damage to 
the power tool. 
						

							KM 55 R, KM 55 RCEnglish
5 Fuel
Your STIHL power tool uses an oil- 
gasoline mixture for fuel (see the 
chapter on Fuel of your instruction 
manual).
Fueling Instructions
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 carefully so as to allow any pressure build-up in the tank 
to release slowly. Never remove the fuel 
filler cap while the engine is running.
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 
machine.
Different models may be equipped with 
different fuel caps.
Toolless cap with gripTo 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 raised positioning 
marks on the grip of the cap and on the 
fuel tank opening lining up. Using the 
grip, press the cap down firmly while 
turning it clockwise as far as it will go 
(approx. 1/4 turn).
Misaligned, damaged or broken cap
NIf the cap does not drop fully into the 
opening when the positioning marks 
line up and/or if the cap does not 
tighten properly when twisted, the 
base of the cap may be prematurely 
rotated (in relation to the top) to the 
closed position. Such misalignment  Warning!
Gasoline is an extremely 
flammable fuel. If spilled 
and ignited by a spark or 
other ignition source, it 
can cause fire and seri-
ous burn injury or 
property damage. Use extreme caution 
when handling gasoline or fuel mix. Do 
not smoke or bring any fire or flame near 
the fuel or the power tool. Note that 
combustible fuel vapor may escape 
from the fuel system.
Warning!
To reduce the risk of serious injury from 
burns, never attempt to refuel the unit 
until it has been completely removed 
from the operator.
Warning!
Fuel your power tool in well-ventilated 
areas, outdoors. Always shut off the 
engine and allow it to cool before refu-
eling. Gasoline vapor pressure may 
build up inside the fuel tank depending 
on the fuel used, the weather conditions 
and the tank venting system.
Warning!
Check for fuel leakage 
while refueling and dur-
ing operation. If fuel 
leakage is found, do not 
start or run the engine 
until the leak is fixed and 
any spilled fuel has been wiped away. 
Take care not to get fuel on your cloth-
ing. If this happens, change your 
clothing immediately.
Warning!
In order to reduce the risk of fuel spill-
age and fire from an improperly 
tightened fuel cap, correctly position 
and tighten the fuel cap in the fuel tank 
opening.
Fold the grip flush with 
the top of the cap. Grip 
the cap and check for 
tightness. If the grip does 
not lie completely flush 
with the cap and the 
detent on the grip does 
not fit in the correspond-
ing recess in the filler 
opening, or if the cap is 
loose in the filler opening, 
the cap is not properly 
seated and tightened and 
you must repeat the 
above steps.
001BA220 KN 
						

							KM 55 R, KM 55 RC English
6can result from handling, cleaning 
or an improper attempt at 
tightening.
NTo return the cap to the open 
position for installation, turn the cap 
(with the grip up) until it drops fully 
into the tank opening. Next, twist the 
cap counterclockwise as far as it will 
go (approx. 1/4 turn) – this will twist 
the base of the cap into the correct 
position. Then, twist the cap 
clockwise, closing it normally.
NIf your cap still does not tighten 
properly, it may be damaged or 
broken; immediately stop use of the 
unit and take it to your authorized 
STIHL dealer for repair.Screw Cap
See also the Fueling chapter in your 
Instruction Manual for additional 
information.
Before StartingKeep the handles clean and dry at all 
times; it is particularly important to keep 
them free of moisture, pitch, oil, fuel mix, 
grease or resin in order for you to 
maintain a firm grip and properly control 
your power tool.
Starting
Start the engine at least 10 feet (3 m) 
from the fueling spot, outdoors only.
For specific starting instructions, see the 
appropriate section of your 
KombiEngine and KombiTool manuals. 
Place the power tool on firm ground or 
other solid surface in an open area. 
Maintain good balance and secure 
footing.
Once the engine has started, 
immediately blip the throttle trigger, 
which should release the starting throttle 
and allow the engine to slow down to 
idle. Left: Base of cap in closed posi-
tion (with open space)
Right: Base of cap correctly posi-
tioned for installation
001BA227 KN
001BA226 KN
Warning!
Unit vibrations can cause 
an improperly tightened 
fuel filler cap to loosen or 
come off and spill quanti-
ties of fuel. In order to 
reduce the risk of fuel 
spillage and fire, tighten the fuel filler 
cap by hand as securely as possible.
Warning!
Always check your power tool for proper 
condition and operation before starting, 
particularly the throttle trigger, throttle 
trigger lockout, stop switch, cutting 
attachment, deflector and harness. The 
throttle trigger must move freely and 
always spring back to the idle position. 
Never attempt to modify the controls or 
safety devices.
Warning!
Never operate your power tool if it is 
damaged, improperly adjusted or main-
tained, or not completely or securely 
assembled.
Warning!
Check that the spark plug boot is 
securely mounted on the spark plug – a 
loose boot may cause arcing that could 
ignite combustible fumes and cause a 
fire.
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. 
						

							KM 55 R, KM 55 RCEnglish
7 See also the safety precautions on 
Starting in the instruction manual of the 
KombiTool.
Important AdjustmentsIf you cannot set the correct idle speed, 
have your STIHL dealer check your 
power tool and make proper 
adjustments and repairs.
During Operation
Holding and Controlling the Power 
Tool
Always hold the unit firmly with both 
hands on the handles while you are 
working. Wrap your fingers and thumbs 
around the handles.
Your right hand should grip the rear 
handle. This also applies to left-handers.
Working Conditions
Operate and start your power tool only 
outdoors in a well ventilated area. 
Operate it under good visibility and 
daylight conditions only. Work carefully. Warning!
Your power tool is a one-person 
machine. Do not allow other persons in 
the general work area, even when 
starting.
Warning!
To reduce the risk of injury from loss of 
control, do not attempt to drop start 
your power tool.
Warning!
When you pull the starter grip, do not 
wrap the starter rope around your hand. 
Do not let the grip snap back, but guide 
the starter rope to rewind it properly. 
Failure to follow this procedure may 
result in injury to your hand or fingers 
and may damage the starter 
mechanism.
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 adjust-
ment. At correct idle speed, the working 
tool should not move. For directions on 
how to adjust idle speed, see the appro-
priate section of your instruction 
manual.
Warning!
To reduce the risk of injury from loss of 
control, never work on a ladder or on 
any other insecure support.
002BA057 KN
Warning!
As soon as the engine is 
running, this product gen-
erates toxic exhaust 
fumes containing chemi-
cals, such as unburned 
hydrocarbons (including 
benzene) and carbon monoxide, that 
are known to cause respiratory prob-
lems, cancer, birth defects, or other 
reproductive harm. Some of the gases 
(e.g. carbon monoxide) may be color-
less and odorless. To reduce the risk of 
serious or fatal injury/illness from inhal-
ing toxic fumes, never run the machine 
indoors or in poorly ventilated locations. 
						

							KM 55 R, KM 55 RC English
8 Operating Instructions
In the event of an emergency, switch off 
the engine immediately – move the slide 
control / stop switch to 0 or STOP.Catalytic Converter
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  Warning!
Inhalation of certain dusts, especially 
organic dusts such as mold or pollen, 
can cause susceptible persons to have 
an allergic or asthmatic reaction. Sub-
stantial or repeated inhalation of dust 
and other airborne contaminants, in par-
ticular those with a smaller particle size, 
may cause respiratory or other ill-
nesses. Control dust at the source 
where possible. Use good work prac-
tices, such as operating the unit so that 
the wind or operating process directs 
any dust raised by the power tool away 
from the operator. Follow the recom-
mendations of EPA/OSHA/NIOSH and 
occupational and trade associations 
with respect to dust (particulate mat-
ter). When the inhalation of dust cannot 
be substantially controlled, i.e., kept at 
or near the ambient (background) level, 
the operator and any bystanders should 
wear a respirator approved by 
NIOSH/MSHA for the type of dust 
encountered.
Warning!
Do not operate your power tool using 
the starting throttle lock, as you do not 
have control of the engine speed.
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 and burn injury, 
keep the area around the muffler clean. 
Remove excess lubricant and all debris 
such as pine needles, branches or 
leaves. Let the engine cool down sitting 
on concrete, metal, bare ground or solid 
wood away from any combustible 
substances.
Warning!
Never modify your muffler. The muffler 
could be damaged and cause an 
increase in heat radiation or sparks, 
thereby increasing the risk of fire and 
burn injury. You may also permanently 
damage the engine. Have your muffler 
serviced and repaired by your STIHL 
servicing dealer only.
Warning!
Some STIHL power tools 
are equipped with a cata-
lytic converter, which is 
designed to reduce the 
exhaust emissions of the 
engine by a chemical 
process in the muffler. Due to this proc-
ess, 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 inju-
ries, the following specific safety 
precautions must be observed.
Warning!
Since a muffler with a catalytic converter 
cools down less rapidly than conven-
tional mufflers, always set your power 
tool down in the upright position and 
never locate it where the muffler is near 
dry brush, grass, wood chips or other 
combustible materials while it is still hot.
Warning!
An improperly mounted or damaged cyl-
inder housing or a damaged/deformed 
muffler shell may interfere with the cool-
ing process of the catalytic converter. 
To reduce the risk of fire or burn injury, 
do not continue work with a damaged or 
improperly mounted cylinder housing or 
a damaged/deformed muffler shell.