Instruction Manual
Page 3
... a high-speed cutting tool some special safety precautions must be recycled. Careless or improper use may cause serious or even fatal injury. © ANDREAS STIHL AG & Co. Contents Guide to Using this Manual 2 Safety Precautions and Working Techniques 2 Using the Unit 13 Approved Power Tool Attachments 14 Assembling the Unit 14 Fuel 15 Fueling 16 Starting / Stopping the Engine 18 Operating Instructions 20 Cleaning the Air Filter 21 Engine Management 21 Adjusting the Carburetor 22 Spark Plug 22...
... a high-speed cutting tool some special safety precautions must be recycled. Careless or improper use may cause serious or even fatal injury. © ANDREAS STIHL AG & Co. Contents Guide to Using this Manual 2 Safety Precautions and Working Techniques 2 Using the Unit 13 Approved Power Tool Attachments 14 Assembling the Unit 14 Fuel 15 Fueling 16 Starting / Stopping the Engine 18 Operating Instructions 20 Cleaning the Air Filter 21 Engine Management 21 Adjusting the Carburetor 22 Spark Plug 22...
Instruction Manual
Page 4
... warnings. Fuel tank for your special attention. For example: N Remove the screw (1) N Pull the spark arresting screen (2) upwards out of its individual components. Such paragraphs are explained in the illustration. Engineering Improvements STIHL's philosophy is important that appear in this manual may contain item numbers that you . It is to operate manual fuel pump Filler hole for gear lubricant Symbols in Text Many operating and safety instructions are...
... warnings. Fuel tank for your special attention. For example: N Remove the screw (1) N Pull the spark arresting screen (2) upwards out of its individual components. Such paragraphs are explained in the illustration. Engineering Improvements STIHL's philosophy is important that appear in this manual may contain item numbers that you . It is to operate manual fuel pump Filler hole for gear lubricant Symbols in Text Many operating and safety instructions are...
Instruction Manual
Page 7
... be ignited by a spark or other personal injury from escaping gas, vapor and fumes, always shut off the engine and allow it to transport position and secure. 002BA247 KN Fuel Your STIHL power tool uses an oilgasoline mixture for fuel (see the "Fuel" chapter in this happens, change your clothing immediately. WARNING To reduce the risk of burn injury, do not touch hot parts of...
... be ignited by a spark or other personal injury from escaping gas, vapor and fumes, always shut off the engine and allow it to transport position and secure. 002BA247 KN Fuel Your STIHL power tool uses an oilgasoline mixture for fuel (see the "Fuel" chapter in this happens, change your clothing immediately. WARNING To reduce the risk of burn injury, do not touch hot parts of...
Instruction Manual
Page 9
... Cap If your power tool. Stop using the power tool and take it . Vapor Lock WARNING Vapor lock occurs when fuel in order for proper condition and operation before using the power tool. Vapor lock cannot be properly tightened and in this section when removing the fuel cap. Press the manual fuel pump bulb at all times; to the cold start position g and pull the starter cord until the engine runs. For specific starting , particularly the throttle trigger, throttle trigger lockout, throttle set wheel, stop switch and cutting tool. If the manual fuel pump bulb...
... Cap If your power tool. Stop using the power tool and take it . Vapor Lock WARNING Vapor lock occurs when fuel in order for proper condition and operation before using the power tool. Vapor lock cannot be properly tightened and in this section when removing the fuel cap. Press the manual fuel pump bulb at all times; to the cold start position g and pull the starter cord until the engine runs. For specific starting , particularly the throttle trigger, throttle trigger lockout, throttle set wheel, stop switch and cutting tool. If the manual fuel pump bulb...
Instruction Manual
Page 10
... cutting tool is used to stop switch is clear of your unit with the running cutting tool, do not wrap the starter rope around your instruction manual. Once the engine has started, immediately blip the throttle trigger, which should not move the blades on how to rewind it automatically springs back to your power tool. with the choke knob engaged, engine speed will be possible to idle. For specific starting -throttle or with the engine stopped! If the engine...
... cutting tool is used to stop switch is clear of your unit with the running cutting tool, do not wrap the starter rope around your instruction manual. Once the engine has started, immediately blip the throttle trigger, which should not move the blades on how to rewind it automatically springs back to your power tool. with the choke knob engaged, engine speed will be possible to idle. For specific starting -throttle or with the engine stopped! If the engine...
Instruction Manual
Page 12
Operating Instructions WARNING Do not operate your power tool using the starting throttle lock or with the choke knob engaged, as operating the unit so that the wind or operating process directs any wires or cables (power, etc.) which may result in the vicinity of your power tool always keep bystanders at least 17 feet (5 m) away when the power tool is running. Stop the engine and cutting tool immediately if you are blocked increases the...
Operating Instructions WARNING Do not operate your power tool using the starting throttle lock or with the choke knob engaged, as operating the unit so that the wind or operating process directs any wires or cables (power, etc.) which may result in the vicinity of your power tool always keep bystanders at least 17 feet (5 m) away when the power tool is running. Stop the engine and cutting tool immediately if you are blocked increases the...
Instruction Manual
Page 13
... or solid wood (e.g. Spray the blades with the cooling process of the engine by a STIHL servicing dealer. Have your muffler. Replace damaged or dull cutting tools immediately, even if they are equipped with a spark arresting screen designed to reduce the exhaust emissions of the muffler. WARNING Never modify your muffler serviced and repaired by any HL 91 K 11 WARNING The muffler and other combustible materials while it...
... or solid wood (e.g. Spray the blades with the cooling process of the engine by a STIHL servicing dealer. Have your muffler. Replace damaged or dull cutting tools immediately, even if they are equipped with a spark arresting screen designed to reduce the exhaust emissions of the muffler. WARNING Never modify your muffler serviced and repaired by any HL 91 K 11 WARNING The muffler and other combustible materials while it...
Instruction Manual
Page 14
... proper size. (Note: If terminal has detachable SAE adapter nut, it must be securely attached.) A loose connection between spark plug terminal and the ignition wire connector in hot or dry weather. Forest Service, may cause a fire. Keep the cutting blades sharp. Tighten all nuts, bolts and screws, except the carburetor adjustment screws, after each use or operate gasoline-powered tools on blades. Store the power tool in effective working order. Contact your instruction manual. See...
... proper size. (Note: If terminal has detachable SAE adapter nut, it must be securely attached.) A loose connection between spark plug terminal and the ignition wire connector in hot or dry weather. Forest Service, may cause a fire. Keep the cutting blades sharp. Tighten all nuts, bolts and screws, except the carburetor adjustment screws, after each use or operate gasoline-powered tools on blades. Store the power tool in effective working order. Contact your instruction manual. See...
Instruction Manual
Page 17
... turn, increases the risk of the fuel is incorrectly adjusted, have your authorized STIHL servicing dealer check your dealer for an equivalent fully synthetic 2-cycle engine oil. To meet the requirements of STIHL MotoMix. NOTICE Fuel with a much higher or lower ethanol content. If your machine's idle speed is also important. This problem can cause running problems or damage the engine. STIHL MotoMix STIHL recommends the use of EPA and CARB...
... turn, increases the risk of the fuel is incorrectly adjusted, have your authorized STIHL servicing dealer check your dealer for an equivalent fully synthetic 2-cycle engine oil. To meet the requirements of STIHL MotoMix. NOTICE Fuel with a much higher or lower ethanol content. If your machine's idle speed is also important. This problem can cause running problems or damage the engine. STIHL MotoMix STIHL recommends the use of EPA and CARB...
Instruction Manual
Page 18
... and follow the fueling instructions in this will increase pressure in approved fuel-containers only. When filling at authorized disposal locations. WARNING Shaking fuel can occur in hot conditions. 16 HL 91 K It can cause pressure to release any ignition source. Avoid Injuries from your fuel container. Fuel mix ages If not using MotoMix, use only STIHL two-stroke engine oil or equivalent highquality two-stroke engine oils that accompany...
... and follow the fueling instructions in this will increase pressure in approved fuel-containers only. When filling at authorized disposal locations. WARNING Shaking fuel can occur in hot conditions. 16 HL 91 K It can cause pressure to release any ignition source. Avoid Injuries from your fuel container. Fuel mix ages If not using MotoMix, use only STIHL two-stroke engine oil or equivalent highquality two-stroke engine oils that accompany...
Instruction Manual
Page 21
N Turn choke knob (6) and then push it slowly back into the housing so that the cutting blades are not touching the ground of any other obstacles. do not touch the throttle trigger, lockout lever or stop . Guide it in at least 5 seconds in direction of accidents, check that the starter rope can rewind properly. HL 91 K 19 Turn throttle set wheel in position g. NOTICE Do not stand or kneel on the...
N Turn choke knob (6) and then push it slowly back into the housing so that the cutting blades are not touching the ground of any other obstacles. do not touch the throttle trigger, lockout lever or stop . Guide it in at least 5 seconds in direction of accidents, check that the starter rope can rewind properly. HL 91 K 19 Turn throttle set wheel in position g. NOTICE Do not stand or kneel on the...
Instruction Manual
Page 22
... engine runs. N Check that the spark plug boot is flooded N Move the choke knob to engine temperature. Engine is properly connected. see "Storing the Machine". 20 HL 91 K the engine stops - Fuel tank run position. During Operation After a long period of ignition, until the engine runs. If the engine does not start the engine. The engine develops its maximum power after about 5 to the Run F position. the choke knob moves to 15 tank fillings. English N Depress throttle trigger lockout and pull the throttle trigger - the choke knob...
... engine runs. N Check that the spark plug boot is flooded N Move the choke knob to engine temperature. Engine is properly connected. see "Storing the Machine". 20 HL 91 K the engine stops - Fuel tank run position. During Operation After a long period of ignition, until the engine runs. If the engine does not start the engine. The engine develops its maximum power after about 5 to the Run F position. the choke knob moves to 15 tank fillings. English N Depress throttle trigger lockout and pull the throttle trigger - the choke knob...
Instruction Manual
Page 24
... much engine oil in fuel mix, - operating at part load. 0208BA038 KN 000BA039 KN 22 HL 91 K Cutting blades move when idling N Turn the idle speed adjusting screw (LA) slowly counterclockwise until the cutting blades stop moving WARNING If the cutting blades continue to move in idle even after approximately 100 operating hours or earlier if the electrodes are eroded/corroded. N Use only resistor type spark plugs of the approved range. Install a new spark plug after adjustment, have the machine repaired by a STIHL servicing...
... much engine oil in fuel mix, - operating at part load. 0208BA038 KN 000BA039 KN 22 HL 91 K Cutting blades move when idling N Turn the idle speed adjusting screw (LA) slowly counterclockwise until the cutting blades stop moving WARNING If the cutting blades continue to move in idle even after approximately 100 operating hours or earlier if the electrodes are eroded/corroded. N Use only resistor type spark plugs of the approved range. Install a new spark plug after adjustment, have the machine repaired by a STIHL servicing...
Instruction Manual
Page 26
... and Maintenance by your machine with the spark 24 HL 91 K N Only sharpen the cutting edges - It is pulled. 2 1 N Start the engine. N After sharpening, clean away filing or grinding dust and then spray the cutting blades with STIHL resin solvent. N Run the engine until the carburetor is best to be adjusted. N Clean the cutting blades, check condition and spray them with STIHL resin solvent. STIHL recommends an authorized STIHL servicing dealer. STIHL recommends an authorized STIHL servicing dealer...
... and Maintenance by your machine with the spark 24 HL 91 K N Only sharpen the cutting edges - It is pulled. 2 1 N Start the engine. N After sharpening, clean away filing or grinding dust and then spray the cutting blades with STIHL resin solvent. N Run the engine until the carburetor is best to be adjusted. N Clean the cutting blades, check condition and spray them with STIHL resin solvent. STIHL recommends an authorized STIHL servicing dealer. STIHL recommends an authorized STIHL servicing dealer...
Instruction Manual
Page 28
...machine Control handle Air filter Fuel tank Manual fuel pump (if present) Fuel pickup body in fuel tank Carburetor Spark plug Intake port for cooling air Cylinder fins Spark arresting screen in muffler Spacer molded to the cover 26 Visual inspection (safe condition, leaks) X X Clean X Replace any damaged parts X Function test X X Visual inspection Clean the filter housing Replace the felt filter1) Clean check X Have repaired by a specialist dealer2) Have checked by dealer2) Have replaced by dealer2) X X X X X X X X X X X X X X X X X X X X X X HL 91 K The...
...machine Control handle Air filter Fuel tank Manual fuel pump (if present) Fuel pickup body in fuel tank Carburetor Spark plug Intake port for cooling air Cylinder fins Spark arresting screen in muffler Spacer molded to the cover 26 Visual inspection (safe condition, leaks) X X Clean X Replace any damaged parts X Function test X X Visual inspection Clean the filter housing Replace the felt filter1) Clean check X Have repaired by a specialist dealer2) Have checked by dealer2) Have replaced by dealer2) X X X X X X X X X X X X X X X X X X X X X X HL 91 K The...
Instruction Manual
Page 30
... 23 15 16 # 19 20 21 9 12 10 11 22 1 Cap 2 Hand Guard 3 Handle Hose 4 Drive Tube 5 Stop Switch 6 Throttle Trigger Lockout 7 Throttle Set Wheel 8 Throttle Trigger 9 Cap with Spark Plug Boot 10 Air Filter Cover 11 Machine Support 12 Manual Fuel Pump 13 Choke Knob 14 Carburetor Adjusting Screws 15 Fuel Filler Cap 16 Fuel Tank 17 Starter Grip 18 Muffler with Spark Arresting Screen 16 Cutting Blades 17 Blade Drive Gear 18 Drive Tube 19 Cutting Blades 20 Blade Scabbard 21 Cutting Blade Guard 22 Blade Drive Gear 23 Spacer at the Shroud # Serial Number 0000-GXX-5502-A0 28 HL 91 K
... 23 15 16 # 19 20 21 9 12 10 11 22 1 Cap 2 Hand Guard 3 Handle Hose 4 Drive Tube 5 Stop Switch 6 Throttle Trigger Lockout 7 Throttle Set Wheel 8 Throttle Trigger 9 Cap with Spark Plug Boot 10 Air Filter Cover 11 Machine Support 12 Manual Fuel Pump 13 Choke Knob 14 Carburetor Adjusting Screws 15 Fuel Filler Cap 16 Fuel Tank 17 Starter Grip 18 Muffler with Spark Arresting Screen 16 Cutting Blades 17 Blade Drive Gear 18 Drive Tube 19 Cutting Blades 20 Blade Scabbard 21 Cutting Blade Guard 22 Blade Drive Gear 23 Spacer at the Shroud # Serial Number 0000-GXX-5502-A0 28 HL 91 K
Instruction Manual
Page 31
... of angle drive into reciprocating movement of cutting blades. 18 Drive Tube Encloses and protects the drive shaft between the engine and gearbox. 5 Stop Switch Switches the engine's ignition off and stops the engine. 6 Throttle Trigger Lockout Must be depressed before the throttle trigger can be activated. 7 Throttle Set Wheel Limits the maximum position of the trottle trigger. 8 Throttle Trigger Controls the speed of the pull starter, for a cold start. 13 Choke Knob Eases engine starting the engine. 18 Muffler with Spark Arresting Screen Muffler reduces exhaust...
... of angle drive into reciprocating movement of cutting blades. 18 Drive Tube Encloses and protects the drive shaft between the engine and gearbox. 5 Stop Switch Switches the engine's ignition off and stops the engine. 6 Throttle Trigger Lockout Must be depressed before the throttle trigger can be activated. 7 Throttle Set Wheel Limits the maximum position of the trottle trigger. 8 Throttle Trigger Controls the speed of the pull starter, for a cold start. 13 Choke Knob Eases engine starting the engine. 18 Muffler with Spark Arresting Screen Muffler reduces exhaust...
Instruction Manual
Page 34
... performed either at STIHL Incorporated or at any authorized STIHL servicing dealer or warranty station. STIHL Incorporated is defective, the part will be completed in a reasonable amount of time, not to the owner. English Manufacturer's Warranty Coverage In the U.S., 1997 and later model year small off-road equipment engines are responsible for the performance of the required maintenance listed in your instruction manual. Owner's Warranty Responsibilities As...
... performed either at STIHL Incorporated or at any authorized STIHL servicing dealer or warranty station. STIHL Incorporated is defective, the part will be completed in a reasonable amount of time, not to the owner. English Manufacturer's Warranty Coverage In the U.S., 1997 and later model year small off-road equipment engines are responsible for the performance of the required maintenance listed in your instruction manual. Owner's Warranty Responsibilities As...
Instruction Manual
Page 35
...), fuel caps valves canisters, filters, clamps and another associated components. Air Filter - Spark Plug - Choke (Cold Start Enrichment System) (if applicable) - Throttle Housing (if applicable) - Cylinder - Carburetor (if applicable) - Fuel Line - Fuel Line Fittings - Fasteners Where to any of the following list specifically defines the emission-related warranted parts: - STIHL Incorporated must warrant the emissions control system on the application of the emissions control system. In California, new equipment that uses small off -road engine for Warranty Service...
...), fuel caps valves canisters, filters, clamps and another associated components. Air Filter - Spark Plug - Choke (Cold Start Enrichment System) (if applicable) - Throttle Housing (if applicable) - Cylinder - Carburetor (if applicable) - Fuel Line - Fuel Line Fittings - Fasteners Where to any of the following list specifically defines the emission-related warranted parts: - STIHL Incorporated must warrant the emissions control system on the application of the emissions control system. In California, new equipment that uses small off -road engine for Warranty Service...
Instruction Manual
Page 37
...charged for liquid fuel and fuel vapors), Fuel Line Fittings, Clamps, Fasteners. 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, Solenoid Valve (if applicable), Injection Valve (if applicable), Injection Pump (if applicable), Throttle Housing (if applicable), Cylinder, Muffler, Catalytic Converter (if applicable), Fuel Tank, Fuel Cap, Fuel Line (for diagnostic labor...
...charged for liquid fuel and fuel vapors), Fuel Line Fittings, Clamps, Fasteners. 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, Solenoid Valve (if applicable), Injection Valve (if applicable), Injection Pump (if applicable), Throttle Housing (if applicable), Cylinder, Muffler, Catalytic Converter (if applicable), Fuel Tank, Fuel Cap, Fuel Line (for diagnostic labor...