STIHL KM 55 R Owner\'s Manual (2024)

STIHL KM 55 R

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Instruction Manual Manual de instrucciones

Instruction Manual 1 - 29

Manual de instrucciones 31 - 63

Contents

English

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

Original Instruction ManualPrinted on chlorine-free paper

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

Printing inks contain vegetable oils, paper can be recycled.

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 29

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.

Warning!

Because this KombiEngine is the engine for a high-speed power tool, some special safety precautions must be observed to reduce the risk of per­sonal injury. Careless or improper use may cause serious or even fatal injury.

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© ANDREAS STIHL AG & Co. KG, 2011

0458-461-8621-A. M9.A11.PM.

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KM 55 R, KM 55 RC

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KombiSystem

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.

Guide to Using this Manual

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:

N A 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:

N Loosen the screw (1). N Lever (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:

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.

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.

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Safety Precautions and Working Techniques

Because this KombiEn­gine is the engine for 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 instruction manuals and the safety precautions of your KombiEngine and KombiTool periodically. Careless or improper use 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 instruction manuals. Be sure that anyone using it understands the infor­mation contained in these manuals.

Use your power tool only for the applications described in the instruction manual of the KombiTool you are using.

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 bystand­ers 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 unauthor­ized persons do not use it.

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.

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 dis­ease (Raynaud's phenomenon) or carpal tunnel syndrome.

These conditions reduce the hand's 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

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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 operator's 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.

Warning!

The ignition system of the STIHL unit produces an electromagnetic field of a 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!

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.

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."

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.

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!

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 vehi­cle, properly secure it to prevent turnover, fuel spillage and damage to the power tool.

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Fuel

Your STIHL power tool uses an oil­gasoline mixture for fuel (see the chapter on "Fuel" of your instruction manual).

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.

Fueling Instructions

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 refu­eling. Gasoline vapor pressure may build up inside the fuel tank depending on the fuel used, the weather conditions and the tank venting system.

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.

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 any 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.

Toolless 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 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).

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 correspond­ing 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.

Misaligned, damaged or broken cap

N If 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

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can result from handling, cleaning or an improper attempt at tightening.

Left: Base of cap in closed posi-

tion (with open space)

Right: Base of cap correctly posi-

tioned for installation

N To 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.

N If 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

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 as securely as possible.

See also the "Fueling" chapter in your Instruction Manual for additional information.

Before Starting

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 main­tained, 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.

Keep 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.

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.

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.

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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.

See also the safety precautions on Starting in the instruction manual of the KombiTool.

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 instruction manual.

If 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.

Warning!

To reduce the risk of injury from loss of control, never work on a ladder or on any other insecure support.

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.

English

Warning!

As soon as the engine is running, this product gen­erates toxic exhaust fumes containing chemi­cals, such as unburned

hydrocarbons (including benzene) and carbon monoxide, that are known to cause respiratory prob­lems, cancer, birth defects, or other reproductive harm. Some of the gases (e.g. carbon monoxide) may be color­less and odorless. To reduce the risk of serious or fatal injury/illness from inhal­ing toxic fumes, never run the machine indoors or in poorly ventilated locations.

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Warning!

Inhalation of certain dusts, especially organic dusts such as mold or pollen, can cause susceptible persons to have an allergic or asthmatic reaction. Sub­stantial or repeated inhalation of dust and other airborne contaminants, in par­ticular those with a smaller particle size, may cause respiratory or other ill­nesses. Control dust at the source where possible. Use good work prac­tices, 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 recom­mendations of EPA/OSHA/NIOSH and occupational and trade associations with respect to dust ("particulate mat­ter"). 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.

Operating Instructions

Warning!

Do not operate your power tool using the starting throttle lock, as you do not have control of the engine speed.

In the event of an emergency, switch off the engine immediately – move the slide control / stop switch to 0 or STOP.

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.

Catalytic Converter

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 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 conven­tional 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 cyl­inder housing or a damaged/deformed muffler shell may interfere with the cool­ing 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.

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

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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.

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 make a warranty claim for a component which has not been serviced or maintained properly or if nonapproved replacement parts were used, STIHL may deny coverage.

Warning!

Use only identical STIHL replacement parts for maintenance and repair. Use of non-STIHL parts may cause serious or fatal injury.

Strictly follow the maintenance and repair instructions in the appropriate section of your KombiEngine and KombiTool instruction manuals. Please refer to the maintenance charts respectively the maintenance notes in these manuals.

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 KombiEngine and KombiTool instruction manuals. Have such work performed by your STIHL servicing dealer only.

Warning!

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 detachable SAE adapter nut, it must be attached.) A loose con­nection between spark plug boot and the 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 the ignition wire boot removed from the spark plug or with a removed spark plug, since uncontained sparking may cause a fire.

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Warning!

Do not operate your power tool if the muffler is damaged, missing or modi­fied. An improperly maintained muffler will increase the risk of fire and hearing loss. If your muffler was equipped with a spark-arresting screen to reduce the risk of fire, never operate your power tool if the screen is missing or damaged. Remember that the risk of forest fires is greater in hot or dry weather.

Store the power tool in a dry and high or 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" in this manual.

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Approved KombiTools

The following STIHL KombiTools may be mounted on the KombiEngine:

KombiTool Purpose FS-KM Brushcutter with

mowing head

FS-KM Brushcutter with

grass cutting blade

FSB-KM Brushcutter with

mowing head

HL-KM 135° Hedge trimmer,

adjustable HL-KM 0° Hedge trimmer FH-KM 135° Power scythe BG-KM Blower HT-KM Pole pruner BF-KM Pick tines FCB-KM Power edger FCS-KM Power edger KB-KM Bristle brush KW-KM PowerSweep

The barrier bar supplied with the machine must be mounted to the loop handle – see also "Mounting the Loop Handle".

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Mounting the Loop Handle

A barrier bar is supplied with the machine. Attach the barrier bar to the loop handle.

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N Insert square nuts (1) in the barrier

bar (2) – the holes must line up

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N Insert the clamp (3) in the loop

handle (4) and position them together on the shaft (5)

N Position clamp (6) N Position barrier bar (2) – note

position!

N Line up the holes N Insert bolts (7) in the holes – and

screw them into the barrier bar as far as possible

N Fit the loop handle (4) at a distance

of (A) approx. 20 cm (8 in) forward of the control handle (8)

N Orient the loop handle N Tighten the bolts – lock the nuts if

necessary

The sleeve (9) is present depending on the country and must be located between the loop handle and control handle.

Always leave the barrier bar attached.

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Fuel

This engine is certified to operate on unleaded gasoline and the STIHL two­stroke engine oil at a mix ratio of 50:1.

Your engine requires a mixture of high­quality gasoline and quality two-stroke air cooled engine oil.

Use mid-grade unleaded gasoline with a minimum octane rating of 89 (R+M/2). If the octane rating of the mid-grade gasoline in your area is lower, use premium unleaded fuel.

Fuel with a lower octane rating may increase engine temperatures. This, in turn, increases the risk of 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 and catalytic converters as well. This could cause running problems or even damage the engine. For this reason STIHL recommends that you use only high-quality unleaded gasoline!

Gasoline with an ethanol content of more than 10% can cause running problems and major damage in engines with a manually adjustable carburetor and should not be used in such engines.

Engines equipped with M-Tronic can be run on gasoline with an ethanol content of up to 25% (E25).

Use only STIHL two-stroke engine oil or equivalent high-quality two-stroke engine oils that are designed for use only in air cooled two-cycle engines.

We recommend STIHL HP Ultra 2-Cycle Engine Oil since it is specially formulated for use in STIHL engines.

Do not use BIA or TCW rated (two­stroke water cooled) mix oils or other mix oils that state they are for use in both water cooled and air cooled engines (e.g., outboard motors, snowmobiles, chain saws, mopeds, etc.).

Take care when handling gasoline. Avoid direct contact with the skin and avoid inhaling fuel vapor. When filling at the pump, first remove the canister from your vehicle and place the canister on the ground before filling. Do not fill fuel canisters that are sitting in or on a vehicle.

The canister should be kept tightly closed in order to avoid any moisture getting into the mixture.

The machine‘s fuel tank and the canister in which fuel mix is stored should be cleaned as necessary.

Fuel mix ages

Only mix sufficient fuel for a few days work, not to exceed 3 months of storage. Store in approved fuel-canisters only. When mixing, pour oil into the canister first, and then add gasoline. Close the canister and shake it vigorously by hand to ensure proper mixing of the oil with the fuel.

Gaso­line

US gal. US fl.oz

12.6 2 1/2 6.4 5 12.8

Dispose of empty mixing-oil canisters only at authorized disposal locations.

Oil (STIHL 50:1 or equiva­lent high-quality oils)

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Fueling

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 build­up in the tank to release slowly.

After fueling, tighten fuel cap as

securely as possible by hand.

Starting / Stopping the Engine

Controls

1 Stop switch 2 Throttle trigger lockout 3 Throttle lever 4 Tongue of throttle trigger 5 Catch

Positions of stop switch 6I – normal run position – the engine

is running or can start

70 – engine off – the ignition is

switched off

Starting

N Move the stop switch to I. N Press down the throttle trigger

lockout and hold it there.

N Squeeze the throttle trigger until the

catch on the tongue (4) can be engaged on the housing.

N Now release the throttle trigger,

tongue and trigger lockout in that order. This is the starting throttle position.

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Starting

N Set the choke lever (8) to

g if the engine is cold e for warm start – also use this posi-

tion if the engine has been running but is still cold.

N Press the fuel pump bulb (9) at least

five times – even if the bulb is already filled with fuel.

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N Place the unit on the ground: Check

that the working tool is not touching the ground or any other obstacles – see also "Starting / Stopping the Engine" in the KombiTool instruction manual.

N Make sure you have a safe and

secure footing.

N Hold the unit with your left hand and

press it down firmly – your thumb should be under the fan housing.

Do not stand or kneel on the drive tube.

N Hold the starter grip with your right

hand.

Version without Easy2Start

N Pull the starter grip slowly until you

feel it engage and then give it a brisk strong pull.

Do not pull out the starter rope all the way – it might otherwise

break.

Version with Easy2Start

N Pull the starter grip slowly until you

feel it engage and then pull it out slowly and steadily.

Do not pull out the starter rope all the way – it might otherwise break.

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Both versions

N Do not let the starter grip snap back.

Guide it slowly back into the housing so that the starter rope can rewind properly.

N Crank the engine until it fires – after

no more than five pulls, move the choke lever (8) to e.

N Continue cranking.

As soon as the engine runs

N Squeeze the throttle trigger to

disengage the tongue – the engine will settle down to idle speed.

Your machine is now ready for operation.

Make sure the carburetor is correctly adjusted. The working tool must not move when the engine is idling.

Stopping the engine

N Move the stop switch to 0.

If the engine does not start

N Set the choke lever to N Set the stop switch, lockout lever

and throttle trigger to the starting throttle position.

N Start the engine by pulling the

starter rope briskly – 10 to 20 pulls may be necessary.

If the engine still does not start

N Move the stop switch to 0. N Remove the spark plug – see

"Spark Plug".

N Dry the spark plug. N Crank the engine several times with

the starter to clear the combustion chamber.

N Refit the spark plug – see "Spark

Plug".

N Move the stop switch to I. N Set the choke lever to e – even if

the engine is cold.

N Now start the engine.

Fuel tank run until completely dry

N After refueling, press the fuel pump

bulb at least five times – even if the bulb is filled with fuel.

N Start the engine.

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Operating Instructions

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 the engine to run for a short while at idle speed so that engine heat can be dissipated by the flow of cooling air. This protects engine­mounted components (ignition, carburetor) from thermal overload.

After Finishing Work

Storing for a short period: Wait for the engine to cool down. Empty the fuel tank and keep the machine in a dry place, well away from sources of ignition, until you need it again. For longer out-of­service perionds – see "Storing the Machine".

If you did not move the choke lever to e quickly enough after the engine began to fire, the combustion chamber is flooded.

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Cleaning the Air Filter

If there is a noticeable loss of engine power

N Set the choke lever to g. N Press in the tab (1) and swing the

filter cover (2) down.

N Clean away loose dirt from around

the filter.

Engine Management

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.

N Remove the felt element (3) from

the filter housing (4) and replace it – knock out or blow out as a temporary measure – do not wash.

N Replace damaged parts. N Fit the felt element (3) in the filter

housing (4).

N Close the filter cover so that it snaps

into position.

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Adjusting the Carburetor

The carburetor comes from the factory with a standard setting.

This setting provides an optimum fuel-air mixture under most operating conditions.

With this carburetor it is only possible to adjust the high speed screw within fine limits.

Standard Setting

N Stopping the Engine N Mount the KombiTool complete with

working tool or cutting attachment.

N Check the air filter and replace it if

necessary.

N Have the spark arresting screen in

the muffler checked (not all markets) – see “Inspection and Maintenance by Dealer"

N Turn high speed screw (H)

counterclockwise as far as stop (no more than 3/4 turn).

N Turn the low speed screw (L)

carefully clockwise as far as stop, then turn it back 1.5 turns.

N Start and warm up the engine. N Adjust idle speed with the idle speed

screw (LA) so that the cutting attachment does not move.

Fine Tuning for Operation in Mountains or at Sea Level

A slight correction of the setting of the high speed screw (H) may be necessary if engine power is not satisfactory when operating at high altitude or at sea level.

N Carry out the standard setting. N Warm up the engine for about

3 minutes at full throttle.

Rule of thumb:

Turn the high speed screw (H) about one quarter of a turn for every 1000 m (3300 ft) change in altitude.

At high altitude

N Turn high speed screw (H)

clockwise (leaner) – no further than stop.

At sea level

N Turn high speed screw (H)

counterclockwise (richer) – no further than stop.

It is possible that maximum engine speed may be reached with the standard setting in each case.

Aadjusting Idle Speed

It is usually necessary to change the setting of the idle speed screw (LA) after every correction to the low speed screw (L).

N Warm up the engine for about 3

minutes.

Engine stops while idling

N Turn the idle speed screw (LA)

slowly clockwise until the engine runs smoothly – the working tool or cutting attachment must not move.

Cutting attachment runs when engine is idling

N Turn the idle speed screw (LA)

counterclockwise until the working tool or cutting attachment stops

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moving and then rotate the screw another 1/2 to 1 turn in the same direction.

If the working tool or cutting attachment continues to run when the engine is idling, have your machine checked and repaired by your servicing dealer.

Erratic idling behavior, engine stops even though setting of LA-screw has been corrected, poor acceleration

Idle setting is too lean: N Idle setting is too lean: Rotate the

low speed screw (L) about 1/4 turn counterclockwise until the engine runs and accelerates smoothly.

Erratic idling behavior

Idle setting is too rich N Rotate the low speed screw (L)

about 1/4 turn clockwise until the engine runs and accelerates smoothly.

Spark Plug

If engine is down on power, difficult to start or runs poorly at idling speed, first check the spark plug.

Fit a new spark plug after approx. 100 operating hours or earlier if the

electrodes are badly eroded.

Wrong fuel mix (too much engine oil in the gasoline), a dirty air filter and unfavorable running conditions (mostly at part throttle etc.) affect the condition of the spark plug. These factors cause deposits to form on the insulator nose which may result in trouble in operation.

Removing the Spark Plug

N Move the stop switch to 0.

N Pull off the spark plug boot (1). N Unscrew the spark plug.

Wrong fuel mix (too much engine oil in the gasoline), a dirty air filter and unfavorable running conditions (mostly at part throttle etc.) affect the condition of the spark plug. These factors cause deposits to form on the insulator nose which may result in trouble in operation.

If engine is down on power, difficult to start or runs poorly at idling speed, first check the spark plug.

N Remove spark plug – see "Starting /

Stopping the Engine".

N Clean dirty spark plug. N Check electrode gap (A) and

readjust if necessary – see "Specifications".

N Use only resistor type spark plugs of

the approved range.

Rectify problems which have caused fouling of spark plug:

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N Too much oil in fuel mix. N Dirty air filter. N Unfavorable running conditions,

e.g. operating at part load.

Fit a new spark plug after approx. 100 operating hours or earlier if the

electrodes are badly eroded.

Installing the spark plug

N Screw home the spark plug, fit the

boot and press it down firmly.

Engine Running Behavior

If engine running behavior is unsatisfactory even though the air filter is clean and the carburetor is properly adjusted, the cause may be the muffler.

Have the muffler checked for contamination (carbonization) by your servicing dealer.

STIHL recommends that you have servicing and repair work carried out exclusively by an authorized STIHL servicing dealer.

Warning!

To reduce the risk of fire and burn injury, use only spark plugs authorized by STIHL. Always press spark plug boot (2) snugly onto spark plug terminal (1) of the proper size. (Note: If terminal has detachable SAE adapter nut, it must be 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.

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