Introduction and safety regulations 1 Introduction and safety regulations 1.5 Layout 1.1 General This Workshop Manual can be used in two different This Workshop Manual provides a comprehensive ways: description of how to troubleshoot, repair and test the chainsaw. A description of different safety measures that •...
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Introduction and safety regulations 1.1 General instructions 1.2 Special instructions The workshop where chainsaw repairs are to be done The fuel used in the chainsaw has the following must be equipped with safety equipment as set out in hazardous properties: local regulations.
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Introduction and safety regulations 1.3 Symbols on the chainsaw 1.4 Symbols in this Workshop Manual The following symbols are moulded into the chainsaw casing. This symbol indicates a risk of personal Choke injury if instructions are not followed. Use protective gloves. Fuel pump Use protective goggles.
Technical data 2 Technical data Displacement Bore Stroke Max. power/rpm / cubic inch Ømm/Øinch mm/inch kW/hp / rpm 38.2/2.33 39/1.535 32/1.260 1.5/9000 38.2/2.33 39/1.535 32/1.260 1.6/9000 Spark plug gap Ignition system Air gap Carburettor type mm/inch mm/inch 0.5/0.02 Digital MBU-84 0.3/0.01 Walbro WTA 36 0.5/0.02...
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Technical data Idling speed Engage speed Max. speed Spark plug 3000 /- 200 4200 12500 NGK BPMR7A 3000 /- 200 4200 12500 NGK BPMR7A Fuel tank volume Oil pump capacity Oil tank volume Automatic oil pump Litres/US pint /min Litres/US pint 0.35/0.74 9 cm /min at 9000 rpm...
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Service tools The tools listed here are service tools intended for use on the chainsaw in question. In addition to these tools, a standard set of hand tools is required. Item Description Used for Article number Piston stop Locking the crankshaft 575 29 36-01 Cover plate, exhaust Sealing the exhaust port...
Chain brake 5 Chain brake 5.1 Dismantling WARNING! Exercise care to ensure the spring does not fly out and cause personal injury. Wear protective goggles. 1. Loosen the bar nuts and remove the clutch cover, guide bar and saw chain. See figure 1. 2.
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Chain brake 5.2 Cleaning and inspection • Carefully clean and check all parts. Parts must be replaced if cracked or show signs of other defects. Always use original spare parts. • Measure the thickness of the chain brake band. It must not be less than 0.6 mm at any point. See Figure 5.
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Chain brake 5.4 Function check For this test, the engine must not be running. Check that the chain brake engages as follows: 1. Hold the chainsaw over a stable surface as shown in Figure 9. The distance between the bar and surface is given in the table below.
Chain catcher 6 Chain catcher 6.1 Dismantling the chain catcher 1. Remove the clutch cover. 2. Dismantle the bar and chain. 6.2 Cleaning and inspection Inspect the chain catcher and replace it if it is damaged. See figure 1. 6.3 Assembly 1.
Muffler 7 Muffler 7.1 Dismantling WARNING! Do not touch the muffler until it has cooled. Risk of burn injuries. 1. Remove the cylinder cover. 2. Remove the screw (A) and the muffler cover (B). 3. Remove the bolts (C) and pull out the: - muffler (D), - gasket (E), - cooling plate (F).
Start/stop switch 8 Start/stop switch 8.1 Dismantling 1. Remove the cylinder cover. 2. Remove the air filter. 3. Use a screwdriver to eject the primer bulb (A) from the air filter holder (B). See Figure 1. Fig. 1 4. Remove the screws (C). See Figure 2. 5.
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Start/stop switch 8.4 Function check Clean the mating surfaces and check the resistance as follows: Measure the resistance by connecting a multimeter to the blue cable and the cylinder (earth). See Figure 4. NOTE! The switch must be in the “on” position to give the correct reading.
Throttle trigger lockout, throttle trigger and spring 9 Throttle trigger lockout, throttle trigger and spring 9.1 Dismantling 1. Remove the cylinder cover, air filter, air filter holder and clutch cover. 2. Remove the screw (A) holding the antivibration ele- ment (B). See Figure 1. 3.
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Throttle trigger lockout, throttle trigger and spring 9. Remove the tank unit and front handle. See Figure Fig. 4 10. Remove the screw (J) and the handle cover (K). See Figure 5. 11. Knock out the pin (L) and remove the throttle trigger (M) See Figure 5.
Starter 10 Starter 10.1 Dismantling 1. Loosen the four screws holding the starter to the crankcase. Lift the starter off the chainsaw. See Figure 1. 2. Pull out the handle 20-30 cm (A) and take out the cord from the slot in the starter pulley (B). See Figure 2.
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Starter 10.4 Cord tension check 1. Wind the cord onto the starter pulley and rotate the pulley clockwise until the cord is correctly tensioned. See Figure 5. 2. Pull out the cord completely. 3. In this position it should be possible to turn the pul- ley by hand an additional 1/2 - 3/4 turn.
Ignition system 11 Ignition system 11.1 Test the ignition system If there is a fault in the ignition system the ignition module must be tested before the ignition system is removed. See chapter 20. 11.2 Dismantling 1. Remove the cylinder cover and the starter unit. 2.
6. Remove the screws (A), pawls (B), springs (C) and washers (D). See Figure 2. Fig. 2 7. A special tool (502 51 49-02 )from Husqvarna is required to dismantle and assemble the flywheel. Center the tool on the crankshaft. Select the appropriate screw, supplied with the tool, and fit the screws in the holes for the start hooks.
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Flywheel 8. Mount the screw press in the center and screw it down far enough to ensure it is secure in the plate. Lock the outer socket with a wrench and screw in the centre screw until the flywheel releases. See Figure 4.
Centrifugal clutch 13 Centrifugal clutch 13.1 Dismantling 1. Make sure that the chain brake is disengaged. 2. Remove the cylinder cover. 3. Remove the clutch cover, bar and chain. 4. Disconnect the spark plug cable. Remove the spark plug and fit piston stop 502 54 15-01 in its place. 5.
Lubrication system 14 Lubrication system WARNING! Insufficient lubrication of the chain can result in the chain breaking, which can cause serious or even life-threatening injury. The lubrication system consists of the following parts: • Oil pump • Suction hose with filter •...
Carburettor 15 Carburettor WARNING! The fuel used in the chainsaw has the following hazardous properties: 1. The fluid and its vapour are poison- ous. 2. Can cause skin irritation. 3. Is highly inflammable. 15.1 Description The drawings accompanying this description do not cor- respond with the carburettor on the chainsaw.
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Carburettor 15.3 Function The carburettor operates differently in the following modes: • Cold start mode • Idling mode • Part throttle mode • Full throttle mode In the cold start mode (see Figure 4) the choke valve (H) is fully closed. This increases the vacuum in the car- burettor so that fuel is sucked more easily from all the diffuser jets (D, E and F).
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Carburettor 15.4 Dismantling the carburettor 1. Remove the cylinder cover. 2. Remove the air filter. 3. Use a screwdriver to eject the primer bulb (A) from the air filter holder (B). See Figure 8. Fig. 8 4. Remove the screws (C). See Figure 9. 5.
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Carburettor Fig. 12 13. Loosen the screws (A) and remove top cover (B). • That the fuel screen is intact and clean. Remove control diaphragm (C) and gasket (D). • That the inlet manifold is undamaged. See Figure 12. 14. Loosen the screw (E) and lift out the needle valve (I) with the lever arm (F), the axle (H) and the spring (G).
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Carburettor 15.6 Assembly Observe cleanliness when assembling the carburettor. The slightest contamination can cause malfunctions. 1. If throttle and choke valves with shafts, lever arms and springs have been removed, these must be assembled. The springs are tightened 1-2 turns. Lubricate the shaft bearings using a light oil.
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Carburettor 15.8 Manifold 1. Pull the flange (L) off the inlet pipe (J). See Figure Fig. 15 2. Remove the 4 screws. See Figure 16. Fig. 16 3. Remove the insulation wall (K) and inlet pipe (J) from the cylinder. See Figure 17. 15.9 Assemble on the saw 1.
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Carburettor 15.10 Carburettor adjustment WARNING! The guide bar, saw chain and clutch cover must be fitted before the chain saw is started, other-wise the clutch may come loose causing personal injury. WARNING! Wear ear protection when making adjustments with the engine running. WARNING! Do not use the chainsaw until it has been adjusted so that the saw chain is still...
Tank unit 16 Tank unit WARNING! The fuel used in the chainsaw has the following hazardous properties: The fluid and its fumes are poisonous. Can cause skin irritation. Is highly inflammable. 16.1 Dismantling Fuel hoses positions. See Figure 1. NOTE! Fluted pliers may not be used with the fuel hose.
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Tank unit 16.3 Replacing the primer bulb Unsnap the suction hose (B) and return hose (A) from the primer bulb (E). See Figure 1. 16.4 Cleaning and inspection Clean all parts and check that the fuel hose is intact. 16.5 Assembly 1.
Anti-vibration system 17 Anti-vibration system WARNING! The fuel used in the chainsaw has the following hazardous properties: 1. The fluid and its fumes are poisonous. 2. Can cause skin irritation. 3. Is highly inflammable. 17.1 Dismantling 1. Remove the cylinder cover, air filter, air filter holder and clutch cover.
Piston and cylinder 18 Piston and cylinder 18.1 Dismantling 1. Remove: - Cylinder cover - Spark plug - Air filter and air filter holder - Starter unit and air guide plate - Ignition module - Flywheel - Clutch cover - Clutch - Muffler - Anti-vibration element - Oil system...
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Piston and cylinderr 8. Remove the circlips (A) and press out the gudgeon pin (B). Remove the piston. See Figure 3. 9. Remove the piston ring (C). 18.2 Cleaning and inspection Clean all parts, scrape off all the remains of any gasket material and scrape off carbon deposits from the follo- wing surfaces: 1.
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Piston and cylinder 7. That the intake manifold and it’s rubber seals are undamaged. See figure 6. Fig. 6 Faults and causes Score marks on the piston (A). See Figure 7. 1. Incorrect carburettor setting. Too high over-speed. 2. Too low octane fuel. 3.
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Piston and cylinder 2. Place the piston with the arrow facing the exhaust port. Slide the gudgeon pin bearing (D) in and fit the circlips (C). See figure 3. 3. Compress the piston ring with a piston ring squeeze tool (589 55 57-01). Insert the tool into the cylinder and carefully fit the cylinder on the piston.
Bar bolt 19 Bar bolt 19.1 Dismantling 1. Drain the oil tank. 2. Knock through the old guide bar bolts so that they fall into the oil tank. See Figure 1. Fig. 1 3. Remove the bolts from the oil tank. See Figure 2. Fig.
20 Test the ignition 20.1 Spark test Disconnect the spark plug from the cylinder. Connect Ignition Tester to spark plug cap and ground the clip to the cylinder fins. See Figure 1. Adjust the knob to 6 mm gap between the two electrodes, read 6 marks on the corresponding scale.
Troubleshooting 21 Troubleshooting Uneven idling Blocked fuel filter 21.1 General troubleshooting Blocked fuel line Leaking inlet hose (rubber) The different faults which may occur on the chainsaw Loose carburettor mounting are divided into four groups. Within each group Worn throttle valve axle possible operating faults are listed to the left while the Loose throttle valve screw probable fault alternatives are listed to the right.
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Troubleshooting Low power Tank venting clogged Blocked fuel filter Impulse channel leaking Blocked impulse channel The cover on the carburettor pump side is loose Faulty pump diaphragm Blocked air filter Control system sticking Leaking control system (air or fuel) Control system incorrectly as- sembled Loose diaphragm Hole in diaphragm...