1.5 Servicing tools The manual gives information about necessary servicing tools. Always use original tools from Husqvarna. 911 - 001 - 15.02.2019 Introduction - 3...
2 Safety 2.1 Safety definitions The product agrees with the applicable EC directives. Warnings, cautions and notes are used to point out specially important parts of the manual. yyyywwxxxx The rating plate shows serial number. WARNING: Used if there is a risk of injury or yyyy is the production year and ww is death for the operator or bystanders if the the production week.
3 Prepare and do servicing on the product 3.1 Maintenance schedule Maintenance Before After 100 After 40 h operation Clean the external surface. After each operation. Clean the muffler, exhaust pipe and engine from leaves, dirt and unwanted lubri- After each operation. cant.
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Item Description Use for Article number Piston stop To lock the crankshaft 521 54 83-01 Hook for fuel filter To remove the fuel filter 502 50 83-01 T-handle Torx For Torx screws 502 71 31-01 Piston assembly kit To assemble the piston 502 50 70-01 Air gap tool To measure the distance between the...
7 Repair instructions 7.1 Product overview for repair instructions 1. Starter unit 14. Vibration damping system 2. Muffler 3. Spark plug 7.2 To clean and examine the product parts 4. Flywheel • Clean and examine all parts fully. You find more 5.
7.3 Starter 3. Let the pulley rotate slowly rearward to release the tension of the recoil spring. 7.3.1 To disassemble the starter unit 1. Remove the 4 screws and remove the starter unit. 4. Remove the bolt (A) and washer. Carefully remove the starter pulley (B) together with the recoil spring (C).
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4. Lubricate the recoil spring and the stub axle of the starter pulley with Husqvarna grease. 5. Put the starter rope through the opening (H) in the 2. Put the starter pulley in a vise. The new spring is in starter housing.
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6. Put the starter rope handle on the starter rope. 8. Pull the starter rope to make it straight, remove your thumb and let the starter rope wind up. 7. Pull the starter rope up into the notch in the starter pulley.
7.4 Muffler 7.5 Air filter 7.4.1 To disassemble the muffler 7.5.1 To disassemble the air filter 1. Remove the 2 screws and remove the muffler cover. 1. Pull the clips (A) to the side to release the air filter cover (B). The air filter cover is connected to the air 2.
7.6 Flywheel 5. Remove the nut that holds the flywheel. 7.6.1 To disassemble the flywheel 1. Clean around the spark plug. 2. Remove the spark plug cap and the spark plug. 3. Put a piston stop in the spark plug hole. 6.
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8. Remove the locking washers (A) with a screwdriver. 7.6.3 To assemble the flywheel This causes deformation of the 2 washers. Discard 1. Make sure that the key in the flywheel and keyway in the 2 washers. the crankshaft are not damaged. 2.
4. Install the flywheel and attach the nut. Remove the 6. Install the starter unit. piston stop. 5. Put the air gap tool between the flywheel and the ignition module. Refer to Servicing data on page 6 for the correct distance. 7.
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• If the spark plug is dirty, clean it and make sure that 7.7.4 To do a test of the short circuit cable Technical data the electrode gap is correct, refer to • If there is no spark, disconnect the short circuit on page 52 .
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7.7.5 To examine the spark plug cable 4. Put the end of the cable against the stop of the Servicing tools on page 11 . assembly pliers, refer to If there is no spark, do the procedure that follows to Then close the pliers to make the new hole.
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8. Push the cable into the spark plug cap. 7.7.6 To examine the ignition module If there is no spark, do the procedure that follows to examine the connection between the spark plug cable and the spark plug. 1. Remove the starter unit. 9.
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3. Examine the distance between the flywheel magnet 7.7.7 To remove the ignition module and the ignition module with an air gap gauge. Refer 1. Remove the starter unit. Servicing data on page 6 for the correct distance. 4. Adjust the distance, if it is necessary. Loosen the screws and adjust the ignition module until the distance is correct.
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5. Remove the screws and cable (B). Pull up the 7.7.8 To install the ignition module ignition module and spark plug cable. 1. Attach cable (A) to the ignition module. Put the module in the crankcase. Attach the 2 screws and cable (B).
3. Adjust the distance. Tighten the screws when the 5. Install the starter unit. distance is correct. 4. Make sure that the cables are in their correct position. 6. Install the spark plug and the spark plug cap. 7.8 Carburetor 7.8.1 To disassemble the carburetor 1.
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3. Remove the 2 screws. Remove the air filter holder. 6. Remove the 4 screws (F). Note: The carburetor is only attached to the fuel hoses (D) and (E), the transparent hose and the throttle wire (C). 4. Make a note of the positions of the gaskets (A) and (B) as they can easily fall off.
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11. Examine the wear to the lever arm and the needle 7.8.3 To assemble the carburetor valve. 1. Examine that the lever arm is flush with the carburetor housing without a gasket. 12. Carefully lift up check valve (N). 2. Assemble the carburetor parts. 13.
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3. Examine that the carburetor is sealed. 7. Attach the air filter. 8. Close the air filter cover with the clips. 7.8.4 To adjust the carburetor a) Connect a pressure tester to the fuel inlet on the carburetor. Pump up the pressure to 50kPa. To adjust the carburetor means that you adjust the engine to the local conditions such as weather, altitude b) Lower the carburetor in a container with gasoline...
3. Remove the 3 screws and 1 nut. Basic factory adjustments H = high speed jet L = low speed jet 1.75 7.9 Handle and throttle trigger 7.9.1 To disassemble the handle The first 2 steps in the instruction is only necessary when you replace the throttle wire.
11. Remove the transparent fuel hose from the 4. Remove the 3 screws (A). carburetor. 12. Use pliers to open the clamp and remove the fuel hose from the fuel tank. 13. Remove the 6 screws and remove the vibration damping system and the vibration springs.
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9. Remove the clutch shoes from the hub with a small 11. Remove the gasket (A). screwdriver. CAUTION: Use rubber brackets in the vise to prevent damage to the clutch. 10. Remove the 6 screws and remove the gearbox cover. Use a flat screwdriver if it is necessary. 12.
7.11 Cutting equipment 22. Put the clutch drum in the thread holes in the gearbox housing to lock in position. Use a gear drive removal tool to remove the gear drive. Refer to 7.11.1 To remove the cutting equipment Servicing tools on page 11 . 1.
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7.12.2 To remove the cylinder and piston 1. Remove the 2 screws, the throttle wire cover and throttle wire. 2. Remove the 4 screws, the manifold and the gasket. 911 - 001 - 15.02.2019 Repair instructions - 35...
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3. Remove the cylinder cover. 5. Remove the 2 screws, the cylinder and the cylinder base gasket. Put a cloth above the crankcase opening below the piston. 4. Remove the heat shield, if it is attached. 36 - Repair instructions 911 - 001 - 15.02.2019...
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6. Remove the snap rings on the piston pin with a 9. Remove the piston ring, if it is necessary. small flat nose pliers. Hold your finger on the snap ring to make sure it does not eject. 7.12.3 To clean and examine the cylinder and piston CAUTION: Clean carefully.
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• Use a screwdriver to remove dirt particles from the • Put the piston ring in the cylinder and measure the cooling fins. space with an air gap tool. The space must not be more than 1 mm. • Clean all parts. •...
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• Clean and examine the piston ring groove. It must 7.12.6 To assemble the cylinder and piston not be more than 1.6 mm. 1. Lubricate the needle bearing with two-stroke oil and put it into the connecting rod. Make sure the bearing moves freely in the connecting rod.
5. Put a new cylinder base gasket on the crankcase. 7. Use the clamp from the piston assembly kit to compress the piston ring. Carefully push the piston into the cylinder opening. Tighten the 2 screws to Servicing data on page the specified torque.
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7.13.2 To disassemble the crankcase and 4. Use a screwdriver or equivalent to remove the sealing ring from the crankcase halves. crankshaft 1. Remove the 3 screws and disconnect the crankcase CAUTION: Remove the sealing rings halves. carefully. The crankcase is easily damaged. a) Flywheel side.
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a) Flywheel side. 7. Increase the temperature of the crankcase halves to 120ºC with a hot air gun. To get 8. Use a ball bearing removal tool, refer to access to the crankcase and crankshaft on page 40 , to remove the bearings from the crankcase halves. a) Flywheel side.
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b) Clutch side. • Examine the crankshaft bearing. There must be no radial play in the connecting rod. Make sure that there is axial play to sufficiently lubricate the crankshaft bearing. • Examine the crankcase halves for cracks and damages. 7.13.4 To assemble the crankcase and crankshaft 1.
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b) Clutch side. b) Clutch side. 3. Put the sealing ring in the crankcase half on the flywheel side. 2. Put the bearing in the crankcase. Carefully tap the To get removal tool for the ball bearing, refer to access to the crankcase and crankshaft on page 40 , with a rubber hammer until the bearing is in position.
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4. Put the crankshaft in the crankcase half on the 5. Install the gasket to the clutch side of the crankcase flywheel side. Lubricate the stub axle with some half. Lubricate the crankshaft pin with some drops of drops of oil and carefully move the crankshaft into oil and move the crankcase half on the clutch side the bearing.
7.14 Fuel tank 6. Put an assembly sleeve on the crankshaft on the clutch side to prevent damage to the sealing ring. Lubricate the crankshaft with oil and install the 7.14.1 To do a tank venting sealing ring. 1. Drain the fuel tank and put the product with the top down.
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7.14.2 To remove the fuel tank 7.14.3 To clean and examine the fuel filter 1. Empty the fuel tank and put the product with the top 1. Remove the fuel tank cap. down. 2. Pull the fuel hose and the fuel filter from the fuel tank 2.
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6. Put the fuel filter in the tank as shown in the illustration. 7.14.4 Fuel tank cap The fuel tank cap cannot be repaired. If the engine stops after a short period of time or if the O-ring on the fuel tank cap is damaged, the fuel tank cap must be replaced.
8 Troubleshooting 8.1 Troubleshooting Starting The engine is hard to start The stop screw for the throttle does not operate correctly Blocked fuel filter Blocked fuel hose Air in fuel pipes Incorrect/unsatisfactory fuel The needle valve is defective The lever arm of the needle valve is damaged The lever arm of the needle valve does not operate correctly The control diaphragm is damaged The control diaphragm has a defective seal...
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Idle speed (low speed) The idle speed does not become The stop screw for the throttle does not operate correctly stable Blocked fuel filter Blocked fuel hose Air in fuel pipes Incorrect/unsatisfactory fuel The needle valve is defective The carburetor is not attached correctly The lever arm of the needle valve does not operate correctly The needle valve spring is not attached correctly The control diaphragm is damaged...
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High speed Unsatisfactory performance at Blocked fuel filter high speed Blocked fuel hose Air in fuel pipes Incorrect/unsatisfactory fuel Vacuum pulse leakage Blocked vacuum pulse pipe Loose screws on the pump cover Defective pump diaphragm The needle valve is defective The carburetor is not attached correctly The lever arm of the needle valve is damaged The lever arm of the needle valve does not operate correctly...