1.5 Servicing tools The manual gives information about necessary servicing tools. Always use original tools from Husqvarna. 1291 - 001 - 27.09.2019 Introduction - 3...
2 Safety 2.1 Safety definitions Use a protective helmet in locations where objects can fall on you. Use approved Warnings, cautions and notes are used to point out hearing protection. Use approved eye specially important parts of the manual. protection. 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 Servicing schedule The descriptions of the maintenance procedures are in the operator's manual. Maintenance task Before After Every 10 Every 25 each use hours hours Clean the external surfaces. √ Clean the air filter. Replace if it is necessary. √...
• Always use a fuel container with an antispill valve. • If Husqvarna two-stroke oil is not available, use a • If there is some fuel on the container, remove the two-stroke oil of good quality for air-cooled engines.
7.3 Starter 7. Centrifugal clutch 8. Flywheel 7.3.1 To disassemble the starter 9. Cylinder and piston 10. Crankcase and crankshaft WARNING: Use protective glasses to prevent 11. Fuel tank injury to the eyes if the recoil spring ejects. 12. Frame and harness 13.
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6. Let the starter pulley rotate rearward until the spring 7.3.2 To replace the recoil spring in the starter tension stops. housing To disassemble the 1. Disassemble the starter, refer to starter on page 12 . 2. Put the recoil spring in the starter groove of the starter housing.
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5. Put the starter rope through the opening in the 4. Make a small knot on the starter rope and pull the starter housing and the opening in the bearing knot into the handle. journal. 7.3.4 To assemble the starter 1.
7.4 Muffler 7. Tilt the starter slightly forward to make sure that the starter is installed correctly on the cylinder cover and on the muffler. 7.4.1 To remove and install the muffler 1. Remove the 3 screws and the muffler cover. 7.3.5 To replace the starter pawl assembly To disassemble the 1.
4. Make sure that the muffler is correctly attached to 6. Install the air filter in the opposite sequence. the product. 7.5.2 To clean and examine the air filter 7.4.3 To clean and examine the muffler CAUTION: Do not use gasoline to clean the air WARNING: Risk of burn injury or fire.
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4. Connect the fuel hose to a pressure tester. Refer to 7.6.2 To remove the fuel tank from the frame Servicing tools on page 8 . 1. Remove the fuel hoses from the carburetor. 2. Remove the 4 screws and pull up the engine from the fuel tank.
7.7 Carburetor 7.6.4 To remove the fuel filter 1. Pull out the fuel filter through the opening in the fuel 7.7.1 Carburetor structure Servicing tools tank with a fuel filter hook. Refer to on page 8 . 2. Loosen the hose clamp to remove the fuel filter from 1.
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the carburetor. The pulse causes the pump diaphragm When the engine operates at idle speed, the throttle to move up and down in the pump chamber. This valve (11) is in the idle position (3). The idle position movement causes the fuel to move into the carburetor means that the throttle valve of the carburetor is not fully chambers.
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3. Diaphragm 3. Remove the throttle wire from the carburetor (E). 4. Screen 5. Fuel inlet 6. Valve, inlet 7. Gasket 8. Diaphragm 9. Pump 7.7.4 To disassemble the carburetor 1. Turn the engine to get access to the air filter assembly.
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8. Remove the 4 screws (Q). Remove the bellows of 10. Carefully remove the pump diaphragm and its the fuel pump (R), the valve housing (S) and the gasket. Examine the diaphragm for wear, where the control diaphragm. illustration shows (V). Hold the pump diaphragm in front of a light to find holes in the material.
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c) Make sure that the lever arm is flush with the Note: Replace the seat, needle valve and lever arm diaphragm housing. If the lever arm is set too at the same time. The seat of the needle valve must high, too much fuel goes into the carburetor.
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3. Connect the pressure tester to the fuel inlet on the 5. Measure the height (A) of the lever arm and adjust carburetor. Increase the pressure to 50kPa. Refer to the height if it is necessary. Correct height is Servicing tools on page 8 . 4±0.5mm.
3. Turn the idle adjustment screw counterclockwise 3. Connect the ignition tester to the spark plug cap and until the cutting attachment stops. ground the clip to the cylinder. Technical data on page 46 for the Note: Refer to recommended idle speed. 7.8 Ignition system 7.8.1 Introduction The engine has an electronic ignition system fully...
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3. Turn the spring to remove it from the cable. 6. Put the spring into the new hole. 7. Put the cable with the open spring into the other slot in the pliers. Close the pliers to bend the spring. 4.
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10. Use the pliers or a screwdriver to align the spring 5. Disconnect the throttle wire from the carburetor. with the hole in the spark plug cap. 6. Disconnect the cables. CAUTION: Be very careful to prevent damage to the spark plug cap. A damaged spark plug cap can cause an electrical shock.
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8. Remove the 4 screws (C and D) and the cylinder 13. Remove the 2 screws and the 2 washers that hold cover (E). the centrifugal clutch. Remove the centrifugal clutch and the 2 washers between the flywheel and the 9.
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16. Attach the center unit to the flywheel puller. Hold the 3. Attach the flywheel and the centrifugal clutch with flywheel puller and use a wrench to tighten the the spacers and screws as shown in the illustration. center bolt until the flywheel releases. Note: Turn the clutch until you can see the arrows that show the direction of rotation.
7.9 Centrifugal clutch 5. Use a feeler gauge to make sure that the distance between the ignition module and the flywheel is 0.3-0.5 mm. 7.9.1 To remove the centrifugal clutch 1. Pull up the knob and remove the shaft. 2. Remove the 4 screws. Remove the clutch drum assembly.
4. Remove the 2 screws that hold the centrifugal 7.9.2 To clean and examine the centrifugal clutch clutch. Remove the centrifugal clutch and the flat 1. Examine the spring and outer edge for wear and washers that are behind the clutch shoes. damage.
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6. Remove the air filter cover, the air filter and the air 6. Push the wrist pin from the piston with a punch of filter holder. the correct dimension. 7. Remove the carburetor, the distance piece and the heat shield. 7.10.2 To disassemble the cylinder and piston To get access to the 1.
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7.10.3 To clean the cylinder and piston • Make sure that the cylinder does not have score marks. CAUTION: Clean carefully. The soft aluminum parts are easily damaged. • Remove the carbon deposits from these parts: 7.10.5 To examine the piston •...
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• Put the piston ring in the cylinder and measure the 7.10.6 To assemble the cylinder and piston space with an air gap tool. The space must not be 1. Carefully put the piston ring on the piston. Make more than 1 mm. sure that you do not cause damage to the piston ring or the piston.
7.11 Crankshaft and crankcase 5. Attach the G snap rings. 7.11.1 To disassemble the crankshaft and crankcase To get access to the crankshaft and crankcase, you must remove all components of the product. Refer to the manual section for each component for instructions. To disassemble the 1.
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9. Use a hot air gun to increase the temperature of the 7.11.2 To clean and examine the crankshaft and crankcase and the crankcase cover to 110°C. Hit the crankcase crankcase and the crankcase cover against a The crankshaft can not be repaired, it must be replaced wooden block to make the bearings fall out.
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a) Put the bearings in the crankcase and the a) Lubricate the stub axle of the crankshaft and the crankcase cover. large end of the connecting rod with some drops of two-stroke oil. Do not put oil on the threads. b) Use a hot air gun to increase the temperature of the crankcase and crankcase cover to 110°C.
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4. Lubricate the crankshaft journal with some drops of d) Attach the flywheel. two-stroke oil and move the crankcase cover into position. Do not put oil on the threads. 7. Attach and lubricate the cylinder. a) Put the cylinder base gasket (G) in the correct 5.
7.13 Handle and throttle trigger 8. Assemble the remaining parts in the opposite sequence to how they were disassembled. 7.13.1 To disassemble the handle 7.12 Harness frame 1. Remove the 7 screws and 2 nuts. 7.12.1 To remove the engine from the harness frame 1.
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5. Remove the screw (I) and connection plate (J) that 7.13.2 To assemble the handle are attached below the stop switch (H). 1. Assemble the black cable (G) and red cable (F) in the cable retainer (K). Install the cable retainer on the left handle half.
7.14 Gearbox 4. Put the spring (C) on the throttle lock (D) and put it in the correct position on the handle half. Put the throttle trigger (A) on the handle, make sure the end 7.14.1 To remove the gearbox of the spring (B) is in the correct position in the 1.
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7.14.2 To disassemble the gearbox 6. Remove the input shaft assembly (O) from the gearbox. 1. Remove the gearbox from the product. Refer to remove the gearbox on page 40 . 2. Remove the bushing (K). 7. Increase the temperature of the gearbox to approximately 140°C.
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3. Put on protective gloves. Use a hot air gun to 9. Attach the snap ring (L) for the bearing on the output increase the temperature of the angle gear to shaft. approximately 140°C. 4. Put the output shaft into the gearbox. Make sure that the bearings are in their correct positions.
8 Troubleshooting 8.1 Troubleshooting Start The engine is not easy 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.
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Idle speed (low speed) The engine stops at idle speed. The stop screw for the throttle does not operate correctly. Blocked fuel filter. Blocked fuel hose. Air in fuel pipes. The needle valve is defective. Defective heat insulation seal. The lever arm of the needle valve is too high. The lever arm of the needle valve does not operate correctly.
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Increase and decrease speed The engine stops when the speed is de- The lever arm of the needle valve is too high. creased. The lever arm of the needle valve does not operate correctly. The needle valve is worn. Object in the needle valve groove. The engine cannot increase speed.
9 Technical data 9.1 Technical data 333RB Mark II Engine Cylinder displacement, cm 32.6 Cylinder bore, mm Stroke, mm Idle speed, rpm 3000±300 Recommended max speed, rpm 10600 Max. engine output, according to ISO 8893, kW @ rpm 1.0 kW...