Stihl Km 90 R Owners Manual

							KM 90 R
English
19
Installing the Spark Plug
NScrew the spark plug (2) into the 
cylinder and fit the boot (1) (press it 
down firmly).For periods of 3 months or longer
NDrain and clean the fuel tank in a 
well ventilated area.
NDispose of fuel properly in 
accordance with local 
environmental requirements.
NRun the engine until the carburetor 
is dry – this helps prevent the 
carburetor diaphragms sticking 
together.
NThoroughly clean the machine – pay 
special attention to the air filter.
NRemove, clean and check the 
attachment. Coat metal parts with 
corrosion inhibiting oil.
NStore the machine in a dry and 
secure location Keep out of the 
reach of children and other 
unauthorized persons.
Maintenance Work
STIHL recommends that you have 
servicing and repair work carried out 
exclusively by an authorized STIHL 
servicing dealer.
Fuel Pickup Body in Tank
NCheck the pickup body in the fuel 
tank every year and have it replaced 
if necessary.
The pickup body should be positioned in 
the area of the tank shown in the 
illustration.
2
002BA446 KN
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465BA002 KN 
						

							KM 90 R
English
20
Maintenance and Care
The following intervals apply to normal operating conditions only. If your daily work-
ing time is longer or operating conditions are difficult (very dusty work area, etc.), 
shorten the specified intervals accordingly.
before starting work
after finishing work or daily
after each refueling stop
weekly
monthly
every 12 months
if problem
if damaged
as required
Complete machineVisual inspection (condition, leaks)XX
CleanX
Replace any damaged partsXX
Control handle Check operationXX
Air filterVisual inspectionXX
CleanXX
ReplaceX
Manual fuel pump (if fitted)CheckX
Have repaired by servicing dealer
1)X
Pickup body in fuel tankHave checked by servicing dealer
1)X
Have replaced by servicing dealer
1)XXX
Fuel tank CleanXX
CarburetorCheck idle adjustment – the working/cut-
ting attachment must not runXX
Adjust idle speedX
Spark plugAdjust electrode gapX
Replace after every 100 operating hours
Cooling inletsVisual inspectionX
CleanX
Cylinder fins Clean 
2)X
Valve clearanceCheck and, if necessary, have adjusted 
by dealer after first 139 hours of 
operation
1)X
Have combustion chamber (CARB only)cleaned by servicing dealer
1) after first 
139 hours of operation, then every 150 
hours of operationX 
						

							KM 90 R
English
21
Spark arresting screen in mufflerCheckXX
Clean or replaceXX
All accessible screws and nuts (not adjust-
ing screws)RetightenX
Anti-vibration elementsCheck XXX
Have replaced by servicing dealer
1)X
Safety labels ReplaceX
1)STIHL recommends an authorized STIHL servicing dealer.2)Remove shroud - see "Spark Arresting Screen in Muffler" The following intervals apply to normal operating conditions only. If your daily work-
ing time is longer or operating conditions are difficult (very dusty work area, etc.), 
shorten the specified intervals accordingly.
before starting work
after finishing work or daily
after each refueling stop
weekly
monthly
every 12 months
if problem
if damaged
as required 
						

							KM 90 R
English
221Fuel Filler Cap
2Carburetor Adjusting Screws
3Manual Fuel Pump
4Starter Grip
5Muffler with Spark Arresting Screen
6Coupling Sleeve
7Wing Screw
8Loop Handle
9Barrier Bar
10Carrying Ring
11Slide Control
12Throttle Trigger Lockout
13Throttle Trigger
14Spark Plug Boot
15Choke Knob
16Air Filter Cover
17Fuel Tank
18Machine Support
#Serial Number
Main Parts
1
11
16
13
9
7
14
3
4
17
18
8
10
465BA001 KN
#
25
612
15 
						

							KM 90 R
English
23
Definitions
1 Fuel Filler Cap
For closing the fuel tank.
2 Carburetor Adjusting Screws
For tuning the carburetor.
3 Manual Fuel Pump
Provides additional fuel feed for a 
cold start.
4 Starter Grip
The grip of the pull starter, for 
starting the engine.
5 Muffler with Spark Arresting Screen
Muffler reduces exhaust noises and 
diverts exhaust gases away from 
operator.
Spark arresting screen is designed 
to reduce the risk of fire.
6 Coupling Sleeve
Connects drive tube to lower part of 
drive tube (stub shaft).
7Wing Screw
Secures lower part of the drive tube 
(stub shaft).
8 Loop Handle
For easy control of machine during 
cutting work.
9 Barrier Bar
Helps keep user's feet and legs 
clear of the cutting attachment.
10 Carrying Ring
Connects the unit to the harness.
11 Slide Control
For starting throttle, run and stop. 
Keeps the choke partially open 
during starting and switches off the 
ignition to stop the engine.12 Throttle Trigger Lockout
Must be depressed before the 
throttle trigger can be activated.
13 Throttle Trigger
Controls the speed of the engine.
14 Spark Plug Boot
Connects the spark plug with the 
ignition lead.
15 Choke Knob
Eases engine starting by enriching 
mixture.
16 Air Filter Cover
Covers and protects the air filter 
element.
17 Fuel Tank
For fuel and oil mixture.
18 Machine Support
For resting machine on the ground.
EPA / CEPA
The Emission Compliance Period 
referred to on the Emissions 
Compliance Label indicates the number 
of operating hours for which the engine 
has been shown to meet Federal 
emission requirements.
Category
CARB
The Emission Compliance Period used 
on the CARB-Air Index Label indicates 
the terms:
Engine
STIHL one-cylinder, four-stroke engine 
with mixture lubrication
Specifications
A = 300 hours
B = 125 hours
C= 50hours
Extended = 300 hours
Intermediate = 125 hours
Moderate = 50 hours 
						

							KM 90 R
English
24
Ignition system
Electronic magneto ignition
Fuel system
All position diaphragm carburetor with 
integral fuel pump
WeightUsers of this unit should carry out only 
the maintenance operations described 
in this manual. STIHL recommends that 
other repair work be performed only by 
authorized STIHL servicing dealers.
Warranty claims following repairs can be 
accepted only if the repair has been 
performed by an authorized STIHL 
servicing dealer using genuine STIHL 
replacement parts.
Genuine STIHL parts can be identified 
by the STIHL part number, the 
{ logo and, in some cases, by 
the STIHL parts symbol K. The 
symbol may appear alone on small 
parts.Observe all country-specific waste 
disposal rules and regulations.
STIHL products must not be thrown in 
the garbage can. Take the product, 
accessories and packaging to an 
approved disposal site for environment-
friendly recycling.
Contact your STIHL servicing dealer for 
the latest information on waste disposal. Displacement: 1.73 cu. in 
(28.4 cm
3)
Bore: 1.5 in. (38 mm)
Stroke: 0.98 in. (25 mm)
Engine power to 
ISO 8893:1.30 bhp 
(0.95 kW) at 
7000 rpm
Idle speed: 2,800 rpm
Cut-off speed (nomi-
nal value): 10,200 rpm
Valve clearance
Inlet valve: 0.004 in. 
(0.10 mm)
Exhaust valve: 0.004 in. 
(0.10 mm)
Spark plug 
(suppressed): Bosch USR 7AC
Electrode gap: 0.02 in. (0.5 mm)
Fuel tank capacity: 17.9 fl.oz 
(0.53 l)
without fuel. without KombiTool:
KM 90 R 9.9 lbs (4.5 kg)Maintenance and RepairsDisposal
000BA073 KN 
						

							KM 90 R
English
25
Not for California
Your Warranty Rights and Obligations
The U.S. Environmental Protection 
Agency (EPA) and STIHL Incorporated 
are pleased to explain the Emission 
Control System Warranty on your 
equipment type engine. In the U.S. new 
1997 and later model year small off-road 
equipment engines must be designed, 
built and equipped, at the time of sale, to 
meet the U.S. EPA regulations for small 
non road engines. The equipment 
engine must be free from defects in 
materials and workmanship which 
cause it to fail to conform with U.S. EPA 
standards for the first two years of 
engine use from the date of sale to the 
ultimate purchaser.
STIHL Incorporated must warrant the 
emission control system on your small 
off-road engine for the period of time 
listed below provided there has been no 
abuse, neglect or improper maintenance 
of your small off-road equipment engine.
Your emission control system includes 
parts such as the carburetor and the 
ignition system. Also included may be 
hoses, and connectors and other 
emission-related assemblies.
Where a warrantable condition exists, 
STIHL Incorporated will repair your 
small off-road equipment engine at no 
cost to you, including diagnosis (if the 
diagnostic work is performed at an 
authorized dealer), parts, and labor.Manufacturer's Warranty Coverage
In the U.S., 1997 and later model year 
small off-road equipment engines are 
warranted for two years. If any emission-
related part on your engine is defective, 
the part will be repaired or replaced by 
STIHL Incorporated free of charge.
Owner's Warranty Responsibilities
As the small off-road equipment engine 
owner, you are responsible for the 
performance of the required 
maintenance listed in your instruction 
manual. STIHL Incorporated 
recommends that you retain all receipts 
covering maintenance on your small off-
road equipment engine, but STIHL 
Incorporated cannot deny warranty 
solely for the lack of receipts or for your 
failure to ensure the performance of all 
scheduled maintenance.
Any replacement part or service that is 
equivalent in performance and durability 
may be used in non-warranty 
maintenance or repairs, and shall not 
reduce the warranty obligations of the 
engine manufacturer.
As the small off-road equipment engine 
owner, you should be aware, however, 
that STIHL Incorporated may deny you 
warranty coverage if your small off-road 
equipment engine or a part has failed 
due to abuse, neglect, improper 
maintenance or unapproved 
modifications.
You are responsible for presenting your 
small off-road equipment engine to a 
STIHL service center as soon as a 
problem exists. The warranty repairs will 
be completed in a reasonable amount of 
time, not to exceed 30 days.If you have any questions regarding your 
warranty rights and responsibilities, 
please contact a STIHL customer 
service representative at 1-800-467-
8445 or you can write to
STIHL Inc.,
536 Viking Drive, P.O. Box 2015,
Virginia Beach, VA 23450-2015
www.stihlusa.com
Coverage by STIHL Incorporated
STIHL Incorporated warrants to the 
ultimate purchaser and each 
subsequent purchaser that your small 
off-road equipment engine will be 
designed, built and equipped, at the time 
of sale, to meet all applicable 
regulations. STIHL Incorporated also 
warrants to the initial purchaser and 
each subsequent purchaser that your 
engine is free from defects in materials 
and workmanship which cause the 
engine to fail to conform with applicable 
regulations for a period of two years.
Warranty Period
The warranty period will begin on the 
date the utility equipment engine is 
purchased by the initial purchaser and 
you have signed and sent back the 
warranty card to STIHL.
If any emission-related part on your 
engine is defective, the part will be 
replaced by STIHL Incorporated at no 
cost to the owner. Any warranted part 
which is not scheduled for replacement 
as required maintenance, or which is 
scheduled only for regular inspection to 
the effect of "repair or replace as 
necessary" will be warranted for the 
warranty period. Any warranted part 
which is scheduled for replacement as 
STIHL Incorporated Federal 
Emission Control Warranty 
Statement 
						

							KM 90 R
English
26 required maintenance will be warranted 
for the period of time up to the first 
scheduled replacement point for that 
part.
Diagnosis
You, as the owner, shall not be charged 
for diagnostic labor which leads to the 
determination that a warranted part is 
defective. However, if you claim 
warranty for a component and the 
machine is tested as non-defective, 
STIHL Incorporated will charge you for 
the cost of the emission test. Mechanical 
diagnostic work will be performed at an 
authorized STIHL servicing dealer. 
Emission test may be performed either 
at STIHL Incorporated or at any 
independent test laboratory.
Warranty Work
STIHL Incorporated shall remedy 
warranty defects at any authorized 
STIHL servicing dealer or warranty 
station. Any such work shall be free of 
charge to the owner if it is determined 
that a warranted part is defective.
Any manufacturer-approved or 
equivalent replacement part may be 
used for any warranty maintenance or 
repairs on emission-related parts and 
must be provided without charge to the 
owner. STIHL Incorporated is liable for 
damages to other engine components 
caused by the failure of a warranted part 
still under warranty.
The following list specifically defines the 
emission-related warranted parts:
–Air Filter
–Carburetor (if applicable)
–Fuel Pump–Choke (Cold Start Enrichment 
System) (if applicable)
–Control Linkages
–Intake Manifold
–Magneto or Electronic Ignition 
System (Ignition Module or 
Electronic Control Unit)
–Fly Wheel
–Spark Plug
–Injection Valve (if applicable)
–Injection Pump (if applicable)
–Throttle Housing (if applicable)
–Cylinder
–Muffler
–Catalytic Converter (if applicable)
–Fuel Tank
–Fuel Cap
–Fuel Line
–Fuel Line Fittings
–Clamps
–Fasteners
Where to make a Claim for Warranty 
Service
Bring the product to any authorized 
STIHL servicing dealer and present the 
signed warranty card.
Maintenance Requirements
The maintenance instructions in this 
manual are based on the application of 
the recommended 2-stroke fuel-oil 
mixture (see also instruction "Fuel"). 
Deviations from this recommendation regarding quality and mixing ratio of fuel 
and oil may require shorter maintenance 
intervals.
Limitations
This Emission Control Systems 
Warranty shall not cover any of the 
following:
Nrepair or replacement required 
because of misuse, neglect or lack 
of required maintenance,
Nrepairs improperly performed or 
replacements not conforming to 
STIHL Incorporated specifications 
that adversely affect performance 
and/or durability, and alterations or 
modifications not recommended or 
approved in writing by STIHL 
Incorporated,
and
Nreplacement of parts and other 
services and adjustments 
necessary for required maintenance 
at and after the first scheduled 
replacement point. 
						

							KM 90 R
English
27
For California only
Your Warranty Rights and Obligations
The California Air Resources Board 
(CARB) and STIHL Incorporated are 
pleased to explain the emission control 
system warranty on your 2015 and later 
small off-road equipment engine.
In California, new equipment that uses 
small off-road engines must be 
designed, built, and equipped to meet 
the State's stringent anti-smog 
standards. STIHL Incorporated must 
warrant the emissions control system on 
your small off-road engine for the period 
listed below provided there has been no 
abuse, neglect or improper maintenance 
of your small off-road engine.
Your emissions control system may 
include parts such as the carburetor or 
fuel-injection system, the ignition 
system, and catalytic converter. Also 
included may be hoses, belts, 
connectors or other emission-related 
assemblies.
Where a warrantable condition exists, 
STIHL Incorporated will repair your 
small off-road equipment engine at no 
cost to you including diagnosis, parts 
and labor.Manufacturer’s Warranty 
Responsibilities
This emissions control system is 
warranted for two years in California. If 
any emissions-related part on your 
equipment is defective, the part will be 
repaired or replaced by STIHL 
Incorporated free of charge.
Owner’s Warranty Responsibilities
As the small off-road equipment engine 
owner, you are responsible for 
performance of the required 
maintenance listed in your instruction 
manual. STIHL Incorporated 
recommends that you retain all receipts 
covering maintenance on your small off-
road equipment engine, but STIHL 
Incorporated cannot deny warranty 
solely for the lack of receipts or your 
failure to ensure the performance of all 
scheduled maintenance.
As the small off-road equipment engine 
owner, you should however be aware 
that STIHL Incorporated may deny you 
warranty coverage if your small off-road 
equipment engine or a part has failed 
due to abuse, neglect, or improper 
maintenance or unapproved 
modifications.
You are responsible for presenting your 
small off-road equipment engine to a 
STIHL servicing dealer as soon as the 
problem exists. The warranty repairs 
should be completed in a reasonable 
amount of time, not to exceed 30 days. If 
you have any questions regarding your 
warranty rights and responsibilities, 
please contact a STIHL customer 
service representative at 1-800-467-
8445 or you can write toSTIHL Inc., 536 Viking Drive,
P.O. Box 2015,
Virginia Beach, VA 23450-2015.
www.stihlusa.com
Coverage by STIHL Incorporated
STIHL Incorporated warrants to the 
ultimate purchaser and each 
subsequent purchaser that your small 
off-road equipment engine is designed, 
built and equipped, at the time of sale, to 
meet all applicable emission 
regulations.
STIHL Incorporated also warrants to the 
initial purchaser and each subsequent 
purchaser that your engine is free from 
defects in materials and workmanship 
which cause the engine to fail to conform 
to applicable emission regulations for a 
period of two years.
Defects Warranty Period
The warranty periods will begin on the 
date the utility equipment engine is 
purchased by the initial purchaser. If any 
emission-related part on your engine is 
defective, the part will be replaced by 
STIHL Incorporated at no cost to the 
owner.
Add-on or modified parts that are not 
exempted by CARB may not be used. 
The use of any non-exempted add-on or 
modified parts will be grounds for 
disallowing a warranty claim. STIHL 
Incorporated will not be liable to warrant 
failures of warranted parts caused by the 
use of a non-exempted add-on or 
modified part.
STIHL Incorporated 
California Exhaust and 
Evaporative Emissions 
Control Warranty Statement 
						

							KM 90 R
English
28 The warranty on emissions-related parts 
will be interpreted as follows:
1.Any warranted part that is not 
scheduled for replacement as 
required maintenance in the written 
instructions required in the 
Emission Warranty Parts List (see 
below) must be warranted for the 
warranty period defined in 
Subsection COVERAGE BY STIHL 
INCORPORATED, see above. If 
any such part fails during the period 
of warranty coverage, it must be 
repaired or replaced by the 
manufacturer according to 
Subsection (4) below. Any such part 
repaired or replaced under the 
warranty must be warranted for the 
remaining warranty period.
2.Any warranted part that is 
scheduled only for regular 
inspection in the written instructions 
required by the Emission Warranty 
Parts List (see below) must be 
warranted for the warranty period 
defined in Subsection COVERAGE 
BY STIHL INCORPORATED, see 
above. A statement in such written 
instructions to the effect of "repair or 
replace as necessary" will not 
reduce the period of warranty 
coverage. Any such part repaired or 
replaced under warranty must be 
warranted for the remaining 
warranty period.
3.Any warranted part that is 
scheduled for replacement as 
required maintenance in the written 
instructions required by the 
Emission Warranty Parts List (see 
below) must be warranted for the 
period of time prior to the first 
scheduled replacement point for that part. If the part fails prior to the 
first scheduled replacement, the 
part must be repaired or replaced by 
the engine manufacturer according 
to Subsection (4) below. Any such 
part repaired or replaced under 
warranty must be warranted for the 
remainder of the period prior to the 
first scheduled replacement point 
for the part.
4.Repair or replacement of any 
warranted part under the warranty 
must be performed at a warranty 
station at no charge to the owner.
5.Notwithstanding the provisions of 
Subsection (4) above, warranty 
services or repairs will be provided 
at all manufacturer distribution 
centers that are authorized to 
service the subject engines.
6.The owner must not be charged for 
diagnostic labor that leads to the 
determination that a warranted part 
is in fact defective, provided that 
such diagnostic work is performed 
at a warranty station.
Warranty Work
STIHL Incorporated shall remedy 
warranty defects at any authorized 
STIHL servicing dealer or warranty 
station. Any such work shall be free of 
charge to the owner if it is determined 
that a warranted part is defective. Any 
manufacturer approved or equivalent 
replacement part may be used for any 
warranty maintenance or repairs on 
emission-related parts and must be 
provided without charge to the owner. 
STIHL Incorporated is liable for damages to other engine components 
caused by the failure of a warranted part 
still under warranty.
Emission Warranty Parts List
Air Filter, Carburetor (if applicable), Fuel 
Pump, Choke (Cold Start Enrichment 
System) (if applicable), Control 
Linkages, Intake Manifold, Magneto or 
Electronic Ignition System (Ignition 
Module or Electronic Control Unit), Fly 
Wheel, Spark Plug, Injection Valve (if 
applicable), Injection Pump (if 
applicable), Throttle Housing (if 
applicable), Cylinder, Muffler, Catalytic 
Converter (if applicable), Fuel Tank, 
Fuel Cap, Fuel Line, Fuel Line Fittings, 
Clamps, Fasteners.
Where to make a Claim for Warranty 
Service
Bring the STIHL product to any 
authorized STIHL servicing dealer and 
present the signed STIHL product 
registration card, or the print-out of the 
electronic product registration.
Limitations
The repair or replacement of any 
warranted part otherwise eligible for 
warranty coverage may be excluded 
from such warranty coverage if STIHL 
Incorporated demonstrates that the 
STIHL product has been abused, 
neglected, or improperly maintained, 
and that such abuse, neglect, or 
improper maintenance was the direct 
cause of the need for repair or 
replacement of the part. That 
notwithstanding, any adjustment of a 
component that has a factory installed,