2 Safety 2.1 Safety definitions Use only flexible trimmer line. Warnings, cautions and notes are used to point out specially important parts of the manual. Do not use metal cutting elements. WARNING: Used if there is a risk of injury or death for the operator or bystanders if the instructions in the manual are not obeyed.
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.
Item Description Use for Article number Air gap tool To measure the distance 502 51 34-02 between the flywheel and the ignition module. Piston assembly kit To assemble the piston. 521 54 83-01 Electrode gap tool To adjust the electrode gap. 502 51 91-01 Flywheel removal tool To remove the flywheel.
6 Repair instructions 6.1 Product overview for repair instructions 6.3 To install the loop handle 1. Starter cover 2. Muffler 1. Put the loop handle between the arrows on the 3. Flywheel shaft. 4. Ignition module 2. Tighten the bolt to attach the loop handle to the 5.
6.4 To install the cutting attachment guard 3. Use a pin to lock the shaft in the bracket (B). 1. Attach the bracket (B) to the shaft with the screw 4. Put the trimmer head (E) on the output shaft. (D).
6.7 Starter 4. Remove the screw (A) and the drive disc (B). 6.7.1 To disassemble the starter unit 1. Remove the 8 screws and remove the starter unit. 2. Pull out the rope approximately 30 cm /12 in and put 5.
7. Pull the starter rope to make it straight, remove your thumb and let the starter rope wind up. 3. Lubricate the starter spring and the stub axle of the starter pulley with Husqvarna grease. 4. Put the starter rope handle on the starter rope. 1023 - 001 - 24.04.2019...
8. Attach the starter unit to the crankcase with 8 4. Examine the gasket for damage. screws. 5. Replace all damaged parts. 6.8.3 To assemble the muffler 1. Assemble the muffler in the opposite sequence of disassemble the muffler on page 16 . 6.9 Air filter 6.9.1 To remove the air filter •...
6.10 Flywheel 8. Remove the flywheel from the crankcase with a flywheel removal tool. 6.10.1 To remove the flywheel 1. Remove the clutch cover. 2. Remove the clutch housing. To disassemble 3. Remove the starter cover. Refer to the starter unit on page 14 . To examine the 4.
3. Put the air gap tool between the flywheel and the • Replace the spark plug if it is necessary. ignition module. Attach the screw (A) and then the 6.11.3 To do a test of the ignition module screw (B) to make sure the flywheel are align with the ignition module.
6.11.5 To examine the spark plug cable 4. Put the end of the cable against the stop of the Servicing tools on page 9 . assembly pliers, refer to If there is no spark, do the procedure that follows to Then close the pliers to make the new hole.
8. Push the cable into the spark plug cap. 6.11.6 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. To disassemble 1.
4. Adjust the distance, if it is necessary. Loosen the 6.11.8 To install the ignition module screws and adjust the ignition module until the 1. Attach cable (A) to the ignition module. Put the distance is correct. Tighten the screws to the correct ignition module in the crankcase.
4. Make sure that the cables are in their correct 5. Remove the 4 screws (A). position. To assemble the 5. Install the starter unit. Refer to starter unit on page 15 . 6. Install the spark plug and the spark plug cap. 6.12 Carburetor 6.12.1 To disassemble the carburetor 1.
• Examine the wear to the lever arm and the needle 6.12.3 To assemble the carburetor valve. 1. Examine that the lever arm is flush with the carburetor housing without a gasket. • Clean the valve housing and make sure that the openings are clear.
3. Examine that the carburetor is sealed. increase the quantity of fuel. Less fuel increases the engine speed and a more fuel decreases the engine speed. The idle speed screw controls the throttle position. Turn the idle speed screw clockwise gives fast idle speed, turn it counterclockwise gives lower idle speed.
3. Carefully pull out the short circuit cable from the 7. Remove the throttle trigger lockout (A). throttle handle, and disconnect the connector. 4. Remove the screw (A) on the side of the throttle handle, and push the throttle handle forward onto the shaft.
4. Remove the screw (A) on the side of the throttle 6.14.3 To assemble the centrifugal clutch handle, and push the throttle handle forward onto 1. Install the centrifugal clutch shoes together with the the shaft. spring. 5. Loosen the screw and remove the shaft from the 2.
7. Remove the snap rings on the piston pin with a a) The top of the piston. small flat nose pliers. Hold your finger on the snap b) The combustion chamber of the cylinder. ring to make sure it does not eject. c) The exhaust port of the cylinder.
• Put the piston ring in the cylinder and measure the • Clean and examine the piston ring groove. It must space with an air gap tool. The space must not be not be more than 1.6 mm. more than 1 mm. •...
6.16 Crankshaft and crankcase 6.15.5 To install the cylinder and piston 1. Install the piston. The arrow at the piston top must 6.16.1 To disassemble the crankcase and be in the direction of the exhaust port. Push in the crankshaft piston pin and attach the snap ring.
5. Remove the ball bearings from the crankcase 6.16.2 To clean and examine the crankcase and halves. Increase the temperature of the crankcase crankshaft halves to 120ºC with a hot air gun. The crankshaft cannot be repaired. Replace it if it is worn or damaged.
• Examine the crankshaft bearing. There must be no 3. Put the crankshaft in the crankcase half. Lubricate radial play in the connecting rod. Make sure that the stub axle with some drops of oil and carefully there is axial play to sufficiently lubricate the move the crankshaft into the bearing.
6.17 Fuel tank 3. Remove the transparent fuel hose from the carburetor. Remove the 4 screws. 6.17.1 To do a tank venting test Note: Make a note of how the wires and components are installed before you disassemble them. Make sure to install them correctly to prevent damage when the product is assembled.
7 Troubleshooting 7.1 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...
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...
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...