Workshop Manual Chain Saws Contents General recommendations 1. Safety equipment 2. Starter unit 2 3 17 3. Electrical system 23 4. Fuel system 35 5. Centrifugal clutch 55 6. Lubrication system 65 7. Cylinder and piston 77 8. Crankshaft and crankcase 93 9. Tools 10.
General recommendations Keep this in mind: Special tools – Do not start the engine without the clutch and clutch drum fitted. – Do not touch hot parts such as the silencer and clutch before they have cooled sufficiently to avoid burn injuries. Some work operations in this workshop manual require the use of special tools. In each section where this is appropriate the tool and order number are illustrated. – Avoid getting petrol on bare skin or in the mouth.
1 Safety equipment 1. Contents Dismantling 4 Disassembly 4 Fitting 6 Dismantling, mod. 2054/2055 7 Fitting, mod. 2054/2055 9 Dismantling, mod. 2077/2083 10 Fitting, mod.
1 Safety equipment In addition to the chain brake the chain catcher and right-hand guard on the rear handle are also considered part of the chain saw’s safety equipment. It is obviously important that the chain brake functions as intended, but it is also important that the chain catcher is undamaged and in position. In the event of a chain break this will catch up the chain so that the hand will not be injured.
1 Safety equipment Remove the screws and the cover over the brake spring. Remove the screws and lift off the cover over the brake spring. ! WARNING! The brake spring is tensioned and can slip out of its position. Bend up the brake spring. Use a screwdriver and carefully bend up the spring. Press out the toggle-joint’s bearing pin and lift off the complete brake mechanism. Press out the toggle-joint’s bearing pin by means of a suitable mandrel. Lift off the complete brake mechanism.
1 Safety equipment The brake band must have a minimum thickness of 0.8 mm at the most worn point. Check the wear on the brake band. Remove the screw and replace the brake band. Remove the screw and fit a new brake band. At the most worn point the band must have a thickness of at least 0.8 mm. Otherwise it should be replaced with a new band. 0,8 mm Check after fitting that the brake band does not touch the toggle-joint and obstruct its movement.
1 Safety equipment A Fit the brake mechanism in the clutch cover. Place the brake mechanism in position on the clutch cover. Lubricate the bearing points with thin oil. Press in the toggle-joint’s bearing pin (A) and place the tubular pin (B) in position. Lubricate the bearing points with thin oil. B Press down the brake spring by means of a Phillips screwdriver. Press down the brake spring in the clutch cover by means of a Phillips screwdriver. Fit the cover.
1 Safety equipment Dismantle the protective plate over the guide bar attachment and the chain brake. Remove the protective plate over the guide bar attachment. Release the chain brake! Remove the screws and lift off the chain brake. Release the chain brake! ! WARNING! The brake spring is tensioned with a very large force and can cause personal injury if the brake is not released prior to further work. Remove the plate clamp over the brake spring and bend away the spring.
1 Safety equipment Dismantle the brake mechanism and replace worn or damaged parts. Dissassemble the brake mechanism and replace worn or damaged parts. The brake band should have a minimum thickness of 0.8 mm at the most worn place. 0,8 mm Assembly Mod. 2054/2055 Fit the brake in the reverse order to dismantling. Begin with by fitting the hand guard. Lubricate all moving parts with thin oil. Fit the brake spring and plate clamp over the spring. Fit the brake spring by means of a Phillips screwdriver.
1 Safety equipment Dismantling Dismantling Mod. 2077/2083 Mod. 2077/2083 Dismantle the chain brake’s bearing on the starter unit side. Remove the screw, sleeve and washer for the chain brake’s bearing on the starter unit side. Remove the clutch cover, guide bar and chain. Clean! Remove the clutch cover, guide bar and chain. Remove the screws and lift off the chain brake. Clean from sawdust and dirt.
1 Safety equipment Replace the hand guard’s bearing pin if it is worn. The hand guard’s bearing pin can now easily be replaced. Press out the sprung tubular pin and pull out the plate insert from the hand guard. Press out the spring tensioned tubular pin and pull out the complete plate insert from the hand guard. Replace the insert if the bearing pin is worn. Clean and check all parts. The thickness of the brake band should be at least 0.8 mm.
1 Safety equipment A Fit the brake band (A) and place the toggle-joint in position over its bearing pin (B). Press down the brake band in its rear attachment (A). Place the toggle-joint in position over its bearing pin (B). Make sure that it is correctly positioned. B Press together the brake spring far enough so that the guide pin in the back of the spring housing is released. Press the brake spring over the guide pin. Push the guide sleeve in the spring and outside of the guide pin.
1 Safety equipment Checking of the brake effect Checking of the brake effect Start the engine. Place the saw on a stable surface and start the engine. Hold the handle with both hands and rev up. Release the chain brake by turning the left wrist towards the hand guard without releasing the grip round the front handle. The chain should stop immediately. Hold the handle with both hands and rev up.
1 Safety equipment Fitting, mod. 2036/2040 Fitting mod. 2036/2040 Fit in the reverse order to dismantling. Replace any damaged parts and fit in the reverse order to dismantling. Note the following: ● Make sure that the spring comes on the correct side of the barrier in the throttle control. Check that the throttle cable is correctly fitted. ● Check that the throttle cable's ball lug sits in the recess (1).
1 Safety equipment Dismantling mod. 625/630/670 Dismantling mod. 625/630/670 Press out the fitted pin and dismantle the cover. Press out the fitted pin approx. 13-14 mm so that the throttle control lock comes loose. Dismantle the covers by means of pressing a screwdriver into the back edge of the covers. If the handle is electrically heated see chap. 3 ”Electrical system”. Dismantle the spring and throttle control lock.
1 Safety equipment Fitting mod. 2095 Fitting mod. 2095 Replace damaged or worn parts and fit in the reverse order to dismantling. Replace damaged or worn parts. Fit in the reverse order to dismantling. Pay attention to the following: ● The spring’s straight shank should be fitted in the throttle control lock (1). ● Make sure the throttle wire housing is well pressed down in the recess (2).
2 Starter unit 2.
2 Starter unit ! WARNING! When working on the starter unit wear protective glasses to avoid eye injuries in the event that the return spring flies out. Dismantling Dismantling 1. Dismantle the starter from the engine unit. 1. Remove all screws and lift off the starter. 2. Release the spring tension. 2. Release the spring tension. Pull out the starter cord approx. 30 cm. Brake the cord wheel with the thumb and place the cord in one of the recesses on the pulley. 3.
2 Starter unit 4. Remove the screw and the washer. 4. Remove the screw and washer in the centre of the pulley. 5. Remove the pulley and spring cassette, and return spring. 5. Lift off the pulley carefully. ! 6A.Remove the screws which hold the spring cassette and lift off. WARNING! Wear protective glasses. ! WARNING! Wear protective glasses. The return spring can fly out and cause injury. 6. Dismantle the cover disc and return spring from the starter unit housing.
2 Starter unit B. Press down a new spring in the starter housing. B. Return spring without cassette. Leave the lock shackle round the spring in position. 1. Place the spring over its seat in the starter housing. 2. Press down the spring in the correct position by means of the thumbs and let the lock shackle slide over the spring. 3. Fit the cover plate off the spring. ! ! WARNING! WARNING! Wear protective glasses. Wear protective glasses. Replacing starter cord 1.
2 Starter unit Assembly Assembly 1. Wind the cord approx. 4 turns clockwise round the pulley. 1. Wind the cord approx. 4 turns clockwise round the pulley. 2. Fit the pulley. 2. Lubricate the pulley’s bearing pin and the return spring with a few drops of motor oil or non-freezing lubricant and fit the pulley. Check that the return spring grips the pulley. The spring may require to be bent out further from the bearing pin. 3. Put the washer in place and tighten the screw. 3.
2 Starter unit 5. Assemble the starter in the reverse order to dismantling. 6. Assemble the starter. Pull out the starter cord a little. Put the starter in position. Release the starter cord and check that the pawls grip the pulley. Tighten the screws. NOTE! If the threads in the crankcase (made of plastic) are for any reason damaged an oversize screw (No. 503 21 22-01) is recommended. 503 21 22-01 22 Replacing starter pawls Replacing starter pawls See chapter 3 ”Electrical system”.
3 Electrical system 3.
3 Electrical system The chain saw is fitted with an electronic system consisting of flywheel, ignition coil, and trigger unit. Certain saw models are fitted with a generator system to heat the handles and carburettor. The ignition system is electronic and completely without moving parts. A defective component cannot be repaired and must be replaced.
3 Electrical system Try with a new plug Try with a new plug. If there is no spark disconnect the short circuiting contact. If there is still no spark remove the short circuiting cable from either the ignition module or short circuiting contact. Replace the contact if necessary. If there is no spark the fault lies in the stop contact. Replace the contact. Mod. 2077/2083 Mod. 2077/2083 Check that the earth cable is undamaged and that it has metallic contact with the crankcase.
3 Electrical system Check other cables and connections. Still no spark? Check the other cables and connections for poor contact (dirt, corrosion, cable break and damaged insulation). Tips! Use an Ohm-meter to check if there is a cable break, e.g. as a result of pinching. Check the air gap. Still no spark? Check the air gap between the flywheel permanent magnet and ignition module. The gap should be 0.3 mm (.012"). Use air gap measure 502 51 34-05. 0.3 mm 502 51 34-05 Adjust the air gap.
3 Electrical system 3. Fit the contact spiral on the ignition cable. 3. Fit the contact spiral on the ignition cable and make sure that the wire is folded along the cable. 4. Pull the contact spiral into the spark plug protection. NOTE! It is important that the point of the contact spiral meets the middle of the ignition cable to prevent sparking. Dismantling Dismantling Dismantle the plug, cylinder cover, starter unit, and air bar. Dismantle the plug, cylinder cover, starter unit, and air conductor.
3 Electrical system Remove the flywheel nut. Remove the flywheel nut by means of a suitable socket wrench. Pull off the flywheel. Pull off the flywheel by means of withdrawing tool 502 51 49-01 which is screwed in the hole for the starter pawls. NOTE! Centre the withdrawing tool over the shaft centre. Select suitable screws and tighten the withdrawing tool. 502 51 49-01 Tips! Tips! If the flywheel is tight give a few smart taps with a hammer on the extractor screw.
3 Electrical system Mod. 2054/2055 Mod. 2054/2055 Pull off the flywheel. Pull off the flywheel by means of ball bearing puller No. 504 90 90-01. NOTE! The claws on the tool should be placed on and opposite the permanent magnet on the flywheel so that this is not damaged. Is the flywheel stuck? Lift up the engine unit by holding the tool and hit the tool screw a few times with a hammer. 504 90 90-01 Starter pawls Starter pawls Check the starter pawls for wear and damage.
3 Electrical system When fitting the starter pawls check the following: ● Washer between flywheel and starter pawls. ● The spring is not clenched. ● The starter pawls move freely. ● Use Locktite on the screw. Assembly Assembly Check that the keyway and key in the crankshaft are undamaged. Check that the keyway and key in the crankshaft are undamaged. Fit a new key and make sure that it fits correctly in the keyway. Check that the keyway and the cast key respectively in the flywheel are undamaged.
3 Electrical system Electrically heated handles Electrically heated handles Certain of our chain saws are fitted with electric heating of both the the front and rear handles. The requisite output is generated by a generator placed behind the flywheel. The electrical system is maintenance free and is controlled by means of a switch on the left-hand side of the chain saw. The generator’s max. output is 80 W.
3 Electrical system Clean and measure both handle inserts between points 2 and 3. The switch should be in the switched off position. Correct measurement value: 1.4 - 1.8 Ohm. If the values measured differ from the recommended values measure each insert separately. Connect the instrument between points 4 and 2, and 4 and 3. Correct measurement value for one handle insert: 0.7 - 0.9 Ohm. Checking of the front handle element Connect the measuring instrument between the points 1 and 3.
3 Electrical system Replacing the generator Replacing the generator Replace the generator if it does not provide sufficient voltage. The generator must be replaced if the voltage proves to be insufficient when checked. The generator is placed behind the flywheel. Remove the screws and lift off the generator. Place the new generator in position and centre it before tightening the screws. Place the new generator in position against the crankcase. Check that the cable is not clenched. Use mandrel No.
4 Fuel system 4.
4 Fuel system In addition to the fuel tank and carburettor, the fuel system also includes the air filter, fuel filter and tank vent. All these components interact to ensure that the engine will have the optimum mixture of fuel and air to make it as efficient as possible. Very small deviations in the carburettor setting, or fouling of the air filter, have a great effect on the running and efficiency of the engine.
4 Fuel system Centrifugal cleaning (Turbo) By means of utilising the centrifugal power during the cleaning of the induction air to the carburettor the air filter is guarantied much longer cleaning intervals. By means of the centrifugal power the larger impurities are sorted out since they are thrown out to the periphery of the air shell and out past the cylinder. The air to the carburettor is captured by the ”turbo nozzle” and the finer impurities are effectively absorbed in the air filter.
4 Fuel system Carburettor Carburettor Dismantling, all models Dismantling, all models Dismantle the cylinder cover and carburettor cover and blow clean the carburettor chamber with compressed air. ● Dismantle the cylinder cover and carburettor cover. ● Close the choke valve to prevent dirt entering the engine. ● Blow clean the carburettor chamber with compressed air. Dismantling mod. 2036/2040 Dismantling mod. 2036/2040 Dismantle the carburettor.
4 Fuel system Place the gasket on the carburettor and tighten the screws. Connect the screwdriver guide. Fit the air filter. Tips! Place the carburettor gasket, preferably with gasket paste, on the carburettor. Position the screws through the holes approx. 5 mm to centre the gasket. Tighten the screws. Begin with the righthand side. Connect the screwdriver guide on the carburettor’s adjusting screws. Fit the air filter. Dismantling mod. 2041/2045/ 2050 Dismantling mod.
4 Fuel system Fix the carburettor gasket on the carburettor. Place the filter holder against the carburettor and push in the screws so that they stick out approx. 3 mm to simplify centring to the spacing piece. Fit the carburettor gasket on the carburettor with gasket paste. Make sure that it is turned the right way round so that the impulse channel is not blocked. Place the filter holder against the carburettor and fold in the screwdriver guide over the adjusting screws.
4 Fuel system 6 1 4 3 2 Lift up the carburettor and dismantle: Lift up the carburettor and dismantle: 1. The screwdriver guide for the carburettor’s adjusting screws. 1. The screwdriver guide for the carburettor’s adjusting screws. 2. The ventilation pipe from the nipple on the fuel tank. 2. The ventilation pipe from the nipple on the fuel tank. 3. The carburettor screws. 3. The carburettor screws. 4. The air filter connection. 4. The air filter connection. 5. The choke lever. 5.
4 Fuel system Unscrew the carburettor screws and lift up the carburettor. Unscrew the carburettor screws and lift up the carburettor. NOTE! The screw (A) which holds the vibration damper should not be dismantled. A Fitting mod. 625/630/670 Fitting mod. 625/630/670 Fit the carburettor in the reverse order to dismantling. Fit the carburettor in the reverse order to dismantling. Place the air filter connection and carburettor screws on the carburettor.
4 Fuel system Lift up the carburettor and remove the air filter holder, throttle push rod and fuel pipe. Lift up the carburettor and remove the air filter holder, throttle push rod, and fuel pipe. Fitting mod. 2077/2083 Fitting mod. 2077/2083 Fit the carburettor in the reverse order to dismantling. Fit the carburettor in the following order: 1. Connect the fuel pipe. 2. Connect the throttle push rod. 3. Connect the impulse pipe. 4.
4 Fuel system Lift up the carburettor and release the throttle wire. Lift up the carburettor and give full throttle by turning the throttle shaft. Lift up the throttle wire from the guide and release the tank vent pipe. Fitting mod. 2095 Fitting mod. 2095 Fit the carburettor in the reverse order to dismantling. Fit the carburettor in the reverse order to dismantling. Pay attention to the following: ● Do not forget the brass ring in the suction pipe.
4 Fuel system The pumping section The pumping section This pumps fuel from the tank to the carburettor. The pump diaphragm which pumps fuel from the tank to the carburettor’s metering section is placed here. The diaphragm is activated by the pressure variations in the engine’s crankcase via an impulse channel. If the channel is blocked, e.g. by grease or an incorrectly positioned gasket, the pump will not function and it will not be possible to start the engine.
4 Fuel system Check the needle valve and lever for wear. Check the needle valve for wear on the point and in the groove for the lever. Replace damaged parts with new ones. Check the lever for wear on the groove for the lever and on the contact point to the metering diaphragm. Replace damaged parts with new ones. Remove the pump diaphragm. Check the diaphragm for wear. Remove the screw which holds the cover over the pump diaphragm. Lift off the cover, gasket and diaphragm.
4 Fuel system Dismantle the welch plug (1) and main jet nozzle (2). 1 Drill a small hole in the welch plug (1) and carefully break it loose with a pointed object. Press out the main jet nozzle (2) with a suitable mandrel. 2 Check the valve and valve shafts for wear. Replace if necessary. Dismantle the valve and valve shafts. If these parts are worn the engine will not idle correctly. Always replace the valve and valve shafts at the same time.
4 Fuel system Fit the valve and valve shafts. ● Fit the valve and valve shafts. NOTE! NOTE! Use Locktite on the valve screws. Check that the valve and valve shafts are turned the right way round and that they seal completely tight in closed position. Fit the pump section parts in the reverse order to dismantling. Use Locktite on the valve screws. Tips! Any number designations on the valve should be able to be read from outside. Replace the fuel filter if it is damaged or cannot be cleaned.
4 Fuel system Fit the metering diaphragm. Place the gasket on the carburettor housing followed by the metering diaphragm. Check that the air hole in the cover is open and screw tight the cover. Carburettor setting ! WARNING! When test running the engine in connection with adjusting the carburettor, the clutch and clutch cover must without exception be fitted. Otherwise there is a risk that the clutch can come loose and cause serious personal injury.
4 Fuel system The following rpm are recommended: Low-speed nozzle L Max overspeed Model During running in After running in* 625 11.800 – 11.900 12.500 630 11.700 – 11.900 13.000 670 12.700 – 12.900 13.500 2036 12.200 – 12.400 13.000 2040 12.200 – 12.400 13.000 2041 11.700 – 11.900 12.500 2045 11.700 – 11.900 12.500 2050 11.700 – 11.900 12.500 2054 12.200 – 12.400 13.000 2055 13.700 – 13.900 14.500 2077** 12.700 – 12.900 13.500 2083 12.700 – 12.900 13.500 2095 12.
4 Fuel system B C A Fuel tank vent The tank air vent has a great effect on the function of the carburettor. If it is not functioning either an overpressure or underpressure can develop in the tank. Overpressure results in flooding the carburettor. Underpressure results in diminished or no fuel flow to the carburettor. The purpose of the tank air vent is therefore to maintain atmospheric pressure in the tank during all operating conditions.
4 Fuel system Model 625/630/670 Model 625/630/670 The valve is pressed in the tank on the right-hand side immediately behind the handlebar attachment. The valve is pressed in the tank on the right-hand side immediately behind the handlebar attachment. NOTE! NOTE! The valve is not screwed secure. The valve is not screwed secure. The valve can be replaced as follows: The valve can be replaced as follows: 1. Remove the tank cover completely. 1. Remove the tank cover completely. 2.
Adjustments 1. Low speed needle (L) 2. High speed needle (H) High speed N. Will not run at full throttle O. Low power P. Will not 4 cycle Acceleration and deceleration K. Will not accelerate L. Engine stops when closing throttle M. Over-rich acceleration Idle (Low speed) D. Will not idle E. Rich idle F. Idles with L-needle closed G. Irregular idle H. "L"-needle needs frequent adjustment J. Loads up while idling Start A. Hard starting B. Fuel dripping from carburettor C.
5 Centrifugal clutch 5. Contents Mod. 2036/2040 Dismantling 56 Fitting 57 Mod. 2041/2045/2050 Dismantling 57 Fitting 58 Mod. 2054/2055 Dismantling 59 Fitting 59 Mod. 625 Dismantling 60 Fitting 61 Mod.
5 Centrifugal clutch The centrifugal clutch has the purpose of transferring the power between the engine and the cutting equipment. As the name implies it works according to the centrifugal principle. This principle implies that the clutch’s friction shoes are slung outwards towards the clutch drum at a specific engine speed. When the friction against the drum becomes sufficient it is driven round at the same speed as the engine.
5 Centrifugal clutch Inspect the wear on the clutch drum. The inner diameter must not exceed 64.4 mm. Lift off the clutch drum and inspect it for wear on the drive wheel and friction surface on the clutch shoes. The drum’s inner diameter must not exceed 64.4 mm. Otherwise replace the clutch drum. Fitting mod. 2036/2040 Fitting mod. 2036/2040 Fit the clutch and lubricate the clutch drum’s needle bearing with grease. First place the clutch spring in position in one clutch shoe.
5 Centrifugal clutch The clutch shoes must have a thickness of at least 1 mm. Check that the shoes have a thickness of at least 1 mm at the most worn point. min. 1 mm All three shoes must be replaced at the same time to avoid imbalance. Check the spokes of the clutch centre and the shoe guide grooves for wear. Check that the clutch centre’s spokes are not severely worn or show signs of cracking, and that the guide groove in the clutch shoes is not worn.
5 Centrifugal clutch Place the clutch hub in position. Brace the clutch in a vice and stretch out the spring with a screwdriver so that the third clutch shoe can be fitted. Place the clutch hub in position and brace the clutch in a vice. Use a screwdriver to stretch out the spring so that the third clutch shoe can be pressed in place. If necessary use a pair of flat pliers to get the spring in place. Lubricate the clutch drum’s needle bearing with grease and fit the clutch on the crankshaft.
5 Centrifugal clutch Dismantling, mod. 625 Dismantling, mod. 625 Dismantle the clutch from the crankshaft. Replace the plug with piston stop No. 502 50 33-01 and dismantle the clutch from the crankshaft. 502 50 33-01 Remove the clutch spring. Remove the clutch spring by means of tool No. 502 50 49-01 and a screwdriver. 502 50 49-01 Clean and inspect the clutch parts for damage and wear. Clean and inspect the clutch hub’s spokes and clutch shoes for wear. min.
5 Centrifugal clutch Fitting, mod. 625 Fitting, mod. 625 Place two clutch shoes and the spring on the clutch hub. Place two clutch shoes and the spring on the clutch hub. NOTE! The spring’s coupling point should lie opposite one of the hub’s spokes. Fit the remaining clutch shoe. Fit the remaining clutch shoe. Use tool No. 502 50 49-01 and a screwdriver. 502 50 49-01 Lubricate the clutch drum’s needle bearing by means of a grease gun.
5 Centrifugal clutch Remove the clutch springs with a small screwdriver. Remove the clutch springs with a small screwdriver. Clean and inspect the clutch parts for damage and wear. Clean and inspect the clutch hub’s spokes and clutch shoes for damage. min. 1 mm There must be a thickness of at least 1 mm left at the most worn place on the clutch shoes. All the shoes must be replaced at the same time. Inspect the chain gear and clutch drum’s splines for damage. Replace damaged parts.
Centrifugal clutch Fit the centrifugal clutch on the crankshaft. Do not forget the steel washer next to the oil pump on mod. 630/670 5 Lubricate the clutch drum’s needle bearing with grease, including the connection to the pump pinion. On mod. 630/670 the steel washer next to the oil pump should also be lubricated with grease. Fit the clutch drum and clutch on the crankshaft.
6 Lubricating system 6. Contents Mod. 2036/2040, 2041/2045/2050 Dismantling 66 Fitting 67 Mod. 2054/2055 Dismantling 67 Fitting 68 Mod. 625/630/675 Dismantling 69 Fitting 70 Mod.
6 Lubricating system The chain saw’s lubrication system should ensure that the bar and chain receive an effective and adequate lubrication during different operating conditions and engine speeds. The operation of the oil pump can take place either via the clutch drum or directly by the crankshaft. In the former case the pump is stopped during idling (no unnecessary oil consumption) and in the latter case it works continuously.
6 Lubricating system A Clean the different parts of the pump and inspect them for damage and wear. B Clean the different parts of the oil pump and inspect them for damage and wear. Pay attention to the following points: A. Wear on the pump wheel’s cam curve and guide pin in the pump housing. B. That the pump housing’s inlet and outlet are not blocked. C C. That the rubber connection’s sealing ribs to the pump housing are undamaged. A D. That the pump wheel cogs are undamaged.
6 Lubricating system Remove the oil pump. Remove the screw and clip which holds the oil pump in position. Bend carefully with a screwdriver and pull out the oil pump from the pump housing. Remove the oil pipe. Remove the oil pipe, first at the bar attachment (note from which direction the pipe goes into the the rubber seal) and then at the pump housing. Bend carefully with a screwdriver. Dismantle the oil hose. See chapter 8 ”Crankshaft and crankcase” for the pump gear.
6 Lubricating system Dismantling, mod. 625/630/670 Dismantling, mod. 625/630/670 Bend up the oil pump from the crankcase by means of screwdriver. Dismantle the clutch cover and centrifugal clutch.Remove the screws. Remove the plate from the bar attachment. Stick a screw driver in each recess and bend the oil pump. B Dismantle the oil hose and clean the filter. Lift the oil suction hose out of the oil tank and clean the oil pick-up filter. Check that the pick-up and pressure passages are open.
6 Lubricating system Dismantle the pump piston by tapping the pump housing on a wooden block. 4. Knock the edge of the pump housing against a piece of wood to make the pump piston slide out of the casing. 5. Check the wear of the pin (G) against which the cam curve of the pump drive runs. If worn, the pin should be removed from the housing, turned half and pushed back in its place. Assembly, mod. 625/630/670 G Clean and check all parts for wear and damage.
6 Lubricating system Screw tight the pump gear and lock the screw with Loctite or lock-paint. Fit the lock screw and make sure that it fits in the recess in the axle. Lock the screw with Loctite AA or lock paint. Check that the pump can be rotated easily and that it is easy to move axially. Fit the adjuster shaft. Turn the pump gear so that the cam curve comes to its highest position against the control pin and fit the adjuster shaft.
6 Lubricating system Place the suction hose in the oil tank. Place the suction hose in the oil tank. Place protective sleeve No. 502 50 53-01 on the crankshaft. Use sleeve No. 502 50 53-01 to protect the sealing ring when the pump is fitted into the crankcase. 502 50 53-01 Fit the oil pump in the crankcase and fit the other parts in the reverse order to dismantling. Fit the pump in the crankcase and tighten the three screws. Fit the steel washer closest to the sealing ring and drive wheel.
6 Lubricating system Lift up the oil pick-up hose and clean or replace the filter. Lift up the oil pick-up hose from the oil tank. Use a screwdriver if necessary. Clean the filter with a brush. Fit a new filter if it cannot be cleaned or if it is damaged. Remove the adjusting screw and its lockpin. Dismantle the oil pump. Dismantle the plastic plug and the pump shaft by giving the pump housing a sharp tap on a wooden block.
6 Lubricating system Fit he oil pump in the reverse order to dismantling. Lubricate the pump shaft and gear with grease before it is pushed into the pump housing. Press in the pump shaft as far as it goes and fit the adjusting screw. Screw it in first as far as it goes and then unscrew it: – 3 turns for mod. 2077/2083. – 1 turn for mod. 2095. The pump will now give maximum oil flow. If less oil flow is required turn the screw clockwise. Fit the oil hose in the crankcase. Replace if it is damaged.
6 Lubricating system Oil tank venting Oil tank venting Check that the ventilation functions by increasing the air pressure in the oil tank. In order to avoid a vacuum developing in the oil tank when the oil is consumed, and thereby resulting in inferior chain lubrication, there is a ventilation passage built into the crankcase. There are different ventilation designs, see chapter 8 ”Crankshaft and crankcase”. Check that the ventilation functions by increasing the air pressure in the oil tank.
7 Cylinder and piston 7. Contents Dismantling General 78 Mod. 2036/2040, Mod. 2041/2045/2050 78 Fitting Mod. 2036/2040, Mod. 2041/2045/2050 80 Dismantling Mod. 2054/2055 82 Fitting Mod. 2054/2055 83 Dismantling Mod. 625/630/670, Mod. 2077/2083, Mod. 2095 84 Fitting General 85 Decompression valve 85 Mod. 625/630/670, Mod. 2077/2083, Mod.
7 Cylinder and piston The cylinder and piston are two of the components which are exposed to the greatest tensions in the engine. They must withstand high revs, large heat variations and high pressure. They must also be resistant to wear. Despite these severe working conditions serious piston and cylinder malfunctioning is relatively unusual. A contributory factor to this is the new lining material in the cylinder barrel, new types of lubricants and refined technology during the manufacturing.
7 Cylinder and piston Mod. 2036/2040 Mod. 2036/2040 Remove the bearing holder. Remove the screws which hold the bearing holder to the cylinder. Remove the bearing holder from the cylinder by carefully tapping it with a plastic mallet. WARNING! Do not use a screwdriver to prise off the bearing holder. The thin sealing surfaces can easily be damaged! Lift off the crankshaft. Lift off the crankshaft together with the piston. Note how the crankshaft is positioned so that it can be re-fitted correctly.
7 Cylinder and piston Dismantle the piston from the connecting rod. Remove the piston bolt’s circlips by using a pair of flat pliers and press out the piston bolt from the piston with mandrel No. 505 38 17-05. Note which direction the arrow points to on the piston head to simplify refitting. 505 38 17-05 Fitting Fitting Mod. 2036/2040 Mod. 2036/2040 Fit the piston on the connecting rod. Make sure that the arrow on the piston head is turned towards the exhaust port.
7 Cylinder and piston Fit the cylinder with crankshaft in the crankcase. Fit the cylinder with crankshaft in the crankcase. NOTE! Use Locktite on the screws and tighten them crosswise. Tightening torque: 11 Nm. Re-tighten the cylinder screws. Fit the other parts in the reverse order to dismantling. Check when fitting the adapter that the inlet pipe and impulse channel are correctly positioned and seal tightly. NOTE! The cylinder screws shall be re-tightened.
7 Cylinder and piston 1 4 Check that the bearing holder's rubber seals are undamaged. Check that the rubber seals on the bearing holder are undamaged. Press down the crankshaft’s bearing holder in the bearing seats on the cylinder and tighten the cylinder screws crosswise. Press down the crankshaft’s bearing holder in the bearing seats on the cylinder. It is not necessary to use sealing compound. Tighten the cylinder screws crosswise. Use Locktite on the screws. Tightening torque: 11 Nm.
7 Cylinder and piston Dismantle the piston from the connecting rod. Cover the crankshaft’s bearing housing with a cloth and remove one of the piston bolt’s circlips by using a pair of flat pliers. Press out the piston bolt from the connecting rod and lift off the piston. Fitting Fitting Mod. 2054/2055 Mod. 2054/2055 Fit the piston on the connecting rod. Before fitting the piston and cylinder refer to chapters ”Cleaning, inspection” and ”Analysis and procedure”.
7 Cylinder and piston Press down the cylinder to the crankcase. Fit the cylinder screws and use Loctite on the threads. Press down the cylinder to the crankcase and make sure that the rubber seal to the carburettor chamber is positioned correctly and seals as intended. Fit the cylinder screws. Use Locktite on the threads and tighten them crosswise. Fit the other parts in the reverse order to dismantling. Refer to respective chapters if necessary. Dismantling Dismantling Mod. 625/630/670 Mod.
7 Cylinder and piston Release the cylinder screws and the screw which holds the spring element to the cylinder (mod. 2095). Release the cylinder screws. Use tool 502 50 57-01 (3/16") for mod. 626/630/ 670 and mod. 2095. Use tool 504 90 00-02 for mod. 2077/ 2083. Lift the cylinder and place a cloth in the crankcase opening to prevent dirt from dropping down into the crankcase. 502 50 57-01 Dismantle the piston from the connecting rod. 504 90 00-02 Dismantle the piston from the connecting rod.
7 Cylinder and piston Lubricate the piston bolt’s needle bearing with a few drops of engine oil and fit the piston. Lubricate the piston bolt’s needle bearing with a few drops of engine oil. Align the arrow on the piston head to the exhaust port. Press in the piston bolt and fit the circlips. NOTE! Place a cloth in the crankcase opening to prevent the circlip dropping down into the crankcase if it should fly off.
7 Cylinder and piston Fit the other parts in the reverse order to dismantling. Fit the other parts in the reverse order to dismantling. Mod. 2077/2083 Observe care when fitting the inlet pipe so that it is not damaged. Lubricate with oil so that it will slide more easily on the induction sleeve on the cylinder. Tighten the clip and check that the connection is tight. Tighten the cylinder screws. Tightening torque: 10-12 Nm. Cleaning, inspection The different parts are cleaned after dismantling: 1.
7 Cylinder and piston Insufficient lubrication The piston displays small to medium sized scratches usually opposite the exhaust port. In severe cases the heat development can be so great that material from the piston adheres along the piston skirt and also in the cylinder bore. The piston ring is as a rule undamaged and can move freely in the piston ring groove. Scratches may also be found on the piston’s inlet side. Reasons: Procedures: ● Incorrect carburettor setting. Recommended max.
7 Cylinder and piston Piston seizures resulting from severe carbon deposits Excessive carbon deposits can result in damage similar to that caused by insufficient lubrication. The piston skirt, however, is darker in colour as a result of the hot combustion gases which are pressed past the piston ring. This type of piston damage begins at the exhaust port where carbon deposits can loosen and stick between the piston and cylinder wall. Medium to deep scratches on the exhaust side.
7 Cylinder and piston The guide pin for the piston ring has been pres- Deep and irregular grooves caused by a loose Irregular grooves on the piston's inlet side caused sed up through the piston head. by a broken bearing cage. circlip. Here on the piston's inlet side. Loose vibrated guide pin for piston ring Damage on circlips for the piston bolt Excessively high engine revs can result in the piston ring ends hammering against the guide pin when the piston ring moves in its groove.
7 Cylinder and piston Reasons: Procedure: ● Defective air filter. Small dust particles pass through the filter. Fit a fine-mesh filter. ● The filter is worn out as a result of overcleaning, whereby small holes have been made in the filter material. Check the filter carefully for holes and damage each time it is cleaned. Change the filter if necessary. ● Insufficient maintenance of the filter, e.g. the use of incorrect method or incorrect solvent.
7 Cylinder and piston Service tips Defect: Procedure: Broken cooling fins, damaged threads or broken screw at exhaust port. In severe cases - replace the cylinder. Repair the thread with Heli-Coil. Seizure marks in the cylinder bore (especially at the exhaust port). Rub the damaged part with fine emery cloth to remove adhered aluminium. With deeper seizure scratches the cylinder and piston should be replaced. The surface lining in the cylinder bore is worn (primarily at the head of the cylinder).
8 Crankshaft and crankcase 8. Contents Replacement of sealing ring on magneto side Mod. 625/630/670, mod. 2077/2083, mod. 2095 94 Replacement of sealing ring on clutch side Mod. 625/630/670, mod. 2077/2083, mod. 2095 95 Replacement of bar attachment bolts Mod. 2036/2040, mod. 625/630/670 96 Vibration damper 96 Mod. 2036/2040 Tank unit (crankcase), crankshaft 100 Mod. 2041/2045/2050 Crankcase, crankshaft 101 Mod. 2054/2055 Crankcase, crankshaft 103 Mod.
8 Crankshaft and crankcase The purpose of the crankshaft in the engine is to convert the forward and backward movement of the piston to rotation. In order to do this a stable construction is required which can withstand high pressure, torsional and flexural stress, and also high rotational speeds. The connecting rod is also exposed to high accelerational and retarding tensions when it moves between the top and bottom dead centres.
Crankshaft and crankcase 8 Replacement of sealing ring on the clutch side Replacement of sealing ring on the clutch side Mod. 625/630/670 Mod. 625/630/670 The sealing ring is in the oil pump housing on these models. The sealing ring is in the oil pump housing on these models. Dismantle the oil pump and press out the sealing ring with a suitable mandrel. Dismantle the centrifugal clutch and pump housing. Press in the new sealing ring from the back of the pump housing to approx. 0.
8 Crankshaft and crankcase Fit the new sealing ring with the plate mantle turned outwards. Lubricate the shaft with a few drops of engine oil and place the new sealing ring in position. The plate mantle should be turned outwards. Press in the sealing ring to the crankcase plane with a suitable mandrel. 504 91 28-00 Mod. 2077 Mod. 2077 Fit the oil pump gear on the crankshaft. Fit the oil pump gear on the crankshaft. The milled end of the gear should be towards the sealing ring.
Crankshaft and crankcase 8 Mod. 2036/2040 Mod. 2036/2040 Remove the screws (A) and separate the front handlebar from the rear handle. Fit a new damper. The vibration damper to the cylinder can be replaced after the screws (A) have been removed and the front handlebar has been removed from the rear handle. Remove the screw (B) and fit a new damper. C The vibration damper to the crankcase can be dismantled and replaced when the screw (B) inside the damper has been removed.
8 Crankshaft and crankcase Remove the screws which hold the vibration dampers. These models have 6 vibration dampers – 3 on each side. Remove the screws which hold the dampers on both sides of the chain saw. Separate the engine unit and tank unit so that the vibration dampers become accessible. Separate the engine unit and the tank unit completely, or at least so that the damaged rubber element becomes accessible for replacement. Dismantle the vibration dampers and fit new ones.
Crankshaft and crankcase A 8 Remove the screws and bend away the connection bar far enough so that the screw for the damper element can be removed. Remove the screws which hold the connection bar between the front and rear handles. Remove the screws which hold the vibration dampers on the other side of the chain saw far enough so that the engine section and handle section can be separated.
8 Crankshaft and crankcase Remove the screw (A) and then release the inner screw (B). A Dismantle the rear vibration damper by means of first removing the outer screw (A) and then enter the tool through the spring and release the inner screw (B). Hold tight the nut with a 10 mm U-key. Use tool 504 90 00-02. Fit a new vibration damper in the reverse order to dismantling. B 504 90 00-02 Release both stop screws, bend away the handlebar, and pull out the vibration damper.
Crankshaft and crankcase 8 Crankshaft Crankshaft Dismantle the crankshaft from the cylinder. Dismantle the crankshaft from the cylinder. If necessary refer to chapter 7 ”Cylinder and piston”. Remove the oil pump gear by means of an extractor, including the sealing rings. Lift off the ball bearing. Remove the oil pump gear from the crankshaft by means of extractor 530 03 11-36. Lift off the sealing rings and ball bearings. Inspect the crankshaft. Refer to chapter ”Checking of crankshaft”.
8 Crankshaft and crankcase Dismantle the ball bearings from the crankshaft. Inspect the crankshaft as per the section ”Checking of crankshaft”. Dismantle the ball bearings from the crankshaft by means of extractor No. 504 90 90-01. Inspect the crankshaft as per the section ”Checking of crankshaft”. 504 90 90-01 Dismantle the sealing rings. Press out the sealing rings from the bearing seats by means of mandrel No. 505 36 17-09. 505 38 17-09 Fitting Fitting Fit the ball bearings on the crankshaft.
Crankshaft and crankcase 8 Lubricate the shaft journal on the clutch side with grease and place one bearing seat in position. Lubricate the shaft journal on the clutch side with grease and place one bearing seat in position. Fit the oil pump gear. Fit the oil pump gear by means of tool 502 50 30-09 502 50 30-09 Lubricate the shaft journal on the flywheel side and fit the other bearing seat. Turn both bearing seats so that they lock to each other.
8 Crankshaft and crankcase Crankshaft Crankshaft Dismantling Dismantling Remove the screw which holds the crankshaft’s bearing housing. The crankshaft’s bearing housing is attached in the crankcase with a screw placed to the side of the oil pump. It is accessible from underneath the crankcase. Lift up the crankshaft and bearing housing from the crankcase. Lift up the crankshaft and bearing housing from the crankcase. Separate the bearing housing and crankshaft.
Crankshaft and crankcase 8 Fitting Fitting Fit the ball bearings on the shaft journals. Fit the ball bearings on the shaft journals. Heat the bearings with a heat gun to approx. 150–200° C and push them in position. Fit the oil pump gear and new sealing rings. Heat the oil pump gear with the heat gun to approx. 150–200° C and then push it quickly on the shaft. Lubricate the shaft journals with grease and fit new sealing rings turned with the plate mantle outwards.
8 Crankshaft and crankcase Press out the crankshaft from the flywheel side’s crankcase half. Use the same tool and press out the crankshaft from the flywheel side’s crankcase half. Inspect the crankshaft as per the section ”Checking of crankshaft”. 502 51 61-01 Heat each crankcase half so that the ball bearing can be removed. Heat each crankcase half to 150–200° C by means of a heat gun. Tap the crankcase half against a piece of wood so that the ball bearing falls out.
Crankshaft and crankcase 8 Heat the flywheel side’s crankcase half and put the ball bearing in position. Heat the flywheel side’s crankcase half to 150–200° C and place the ball bearing in position against the shoulder in the bearing seat. Pull the crankshaft into the flywheel side’s crankcase half by means of tool 502 50 30-04 (use the sleeve from 502 50 30-08). Pull the crankshaft into the flywheel side’s crankcase half by means of tool 502 50 30-04 (use the sleeve from 502 50 30-08).
8 Crankshaft and crankcase Check that the crankshaft rotates easily. Check that the crankshaft rotates easily. Fit the sealing ring on the flywheel side. Lubricate the shaft journal with oil and fit the seal on the flywheel side by means of mandrel 506 38 17-09 The plate mantle should be turned outwards. Press in the sealing ring far enough so that it lies level with the conical surface. Mod. 2077/2083 Mod.
Crankshaft and crankcase Press out the crankshaft from the flywheel side’s crankcase half. 8 Press out the crankshaft from the flywheel side’s crankcase half with tool 502 51 61-01. Inspect the crankshaft as per chapter ”Checking of crankshaft”. 502 51 61-01 Dismantle the ball bearings and sealing rings. Clean the crankcase halves and check that the oil tank vent functions. Heat the crankcase halves and dismantle the ball bearings and sealing rings in the same way as described for mod. 625/ 630/670.
8 Crankshaft and crankcase Press the crankcase halves together. Put the flywheel side’s crankcase half in position and press the crankcase halves together by means of tools 502 50 30-13 and 502 50 30-14. Check that the crankcase gasket does not move out of position. Tighten all the crankcase screws. 502 50 30-13 Mod. 2077 502 50 30-14 Mod. 2083 Check that the crankshaft rotates easily. Check that the crankshaft rotates easily. Fit a new sealing ring on the flywheel side.
Crankshaft and crankcase Press the crankcase halves apart. Press out the crankshaft and inspect it for wear and damage. 8 Press apart the crankcase halves and press out the crankshaft in the same way as described for mod. 625/630/670. Inspect the crankshaft as per section ”Checking of crankshaft”. Dismantle the ball bearings and sealing rings. Clean the crankcase halves and check that the oil tank vent functions.
8 Crankshaft and crankcase Check that the guide sleeves are in position and place a new gasket on the sealing surface. Check that the guide sleeves in the flywheel side’s crankcase half are in position and place a new gasket on the sealing surface. Fix it with a little grease. Press the crankcase halves together and tighten the crankcase screws. Place the drive side’s crankcase half in position and press the crankcase halves together by means of tool 502 50 30-08. Tighten the crankcase screws.
Crankshaft and crankcase Check the connecting rod small end. 8 Check the connecting rod small end. If there are signs of seizure marks or discolouring on the bearing race, the crankshaft should be replaced. Check the crankshaft bearing. Check the crankshaft bearing. The connecting rod should not have any radial play (upwards and downwards). It should, however, have axial play in order to ensure adequate lubrication of the crankshaft bearing.
9 Tools 9.
9 Tools Generator Model Oil pump 530 03 11-36 505 38 18-17 502 71 26-01 502 54 09-01 502 71 35-01 502 71 23-01 2036 ● – – – – – 2040 ● – – – – – 2041 – ● – – – – 2045 – ● – – – – 2050 – ● – – – – 2051 – – ● – – ● 2054 – – ● – – – 2055 – – ● – – ● 625 – – – – – – 630 – – – – – – 670 – – – – – – 2077 – – – ● – – 2083 – – – – – – 2094 – – – – ● – 2095 – – – – – – 116
9 Tools Vibration damper Model Clutch 18 mm 11 mm 14 mm 502 54 04-01 530 03 11-12 502 50 49-01 502 50 66-02 502 50 67-01 502 51 00-02 2036 – ● – – – – 2040 – ● – – – – 2041 – – – – – – 2045 – – – – – – 2050 – – – – – – 2051 – – – – – – 2054 – – – – – – 2055 – – – – – – 625 – – ● ● ● ● 630 – – – ● ● ● 670 – – – ● ● ● 2077 ● – ● ● – – 2083 – – – – – – 2094 – – – ● – – 2095 – – – – – – 117
9 Tools Crankshaft Model Ball bearing 502 50 30-04 502 50 30-08 502 50 30-09 502 50 30-13 502 50 30-14 504 90 90-01 2036 – – – – – ● 2040 – – – – – ● 2041 – – ● – – ● 2045 – – ● – – ● 2050 – – ● – – ● 2051 – – – – – ● 2054 – – – – – ● 2055 – – – – – ● 625 ● – – – – ● 630 ● – – – – ● 670 ● – – – – ● 2077 – – – ● – ● 2083 – – – – ● ● 2094 – ● – – – ● 2095 – ● – – – ● 118
9 Tools Model Sealing ring 1 2 1 505 38 17-09 38 17-39 504 91 40-01 502 50 55-01 502 50 53-01 504 91 28-00 504 91 28-06 2036 – – – – – – 2040 – – – – – – 2041 – – – – – ● 2045 – – – – – ● 2050 – – – – – ● 2051 ● – – ● – – 2054 ● – – ● – – 2055 ● – – ● – – 625 ● – ● – ● ● 630 ● – ● – ● ● 670 ● – ● – ● ● 2077 ● ● – – – ● 2083 ● ● – – – ● 2094 ● ● – ● – ● 2095 ● ● – ● – ● 2 505 119
9 Tools Ignition system Model Cylinder and piston 502 50 33-01 504 91 06-05 502 50 70-01 505 38 17-05 502 51 94-01 504 91 08-07 2036 ● – ● ● ● – 2040 ● – ● ● ● – 2041 ● – ● ● – ● 2045 ● – ● ● – ● 2050 ● – ● ● – ● 2051 – ● ● ● – – 2054 – ● ● ● – – 2055 – ● ● ● – – 625 ● – ● ● – – 630 ● – ● ● – – 670 ● – ● ● – – 2077 ● – ● ● – – 2083 ● – ● ● – – 2094 ● – ● ● – – 2095 ● – ● ● – – 120
9 Tools Ignition system Model Crankcase 502 71 13-01 502 50 06-01 502 51 34-05 504 91 08-03 502 51 49-01 502 51 61-01 2036 ● ● ● – – – 2040 ● ● ● – – – 2041 ● ● ● – – – 2045 ● ● ● – – – 2050 ● ● ● – – – 2051 ● ● ● ● – – 2054 ● ● ● ● – – 2055 ● ● ● ● – – 625 ● ● ● ● ● ● 630 ● ● ● ● ● ● 670 ● ● ● ● ● ● 2077 ● ● ● ● ● ● 2083 ● ● ● ● ● ● 2094 ● ● ● ● ● ● 2095 ● ● ● ● ● ● 121
9 Tools Tightness testing Model Chain brake Fuel pick-up 502 54 11-01 503 84 40-01 502 50 38-01 502 50 37-01 502 71 30-01 502 50 83-01 2036 ● ● ● ● – ● 2040 ● ● ● ● – ● 2041 ● ● ● ● ● ● 2045 ● ● ● ● ● ● 2050 ● ● ● ● ● ● 2051 ● ● ● ● ● ● 2054 ● ● ● ● ● ● 2055 ● ● ● ● ● ● 625 ● ● ● ● – ● 630 ● ● ● ● – ● 670 ● ● ● ● – ● 2077 ● ● ● ● – ● 2083 ● ● ● ● – ● 2094 ● ● ● ● – ● 2095 ● ● ● ● – ● 122
9 Tools Model Workshop equipment 504 90 00-01–04 + 505 38 13-08 = 3/16" 3 mm 502 71 14-01 502 51 02-01 503 26 70-01 504 90 00-06 502 50 57-01 504 90 00-04 2036 ● ● ● ● – – 2040 ● ● ● ● – – 2041 ● ● ● ● – – 2045 ● ● ● ● – – 2050 ● ● ● ● – – 2051 ● ● ● ● – – 2054 ● ● ● ● – – 2055 ● ● ● ● – – 625 ● ● ● ● ● ● 630 ● ● ● ● ● ● 670 ● ● ● ● ● ● 2077 ● ● ● ● – – 2083 ● ● ● ● – ● 2094 ● ● ● ● – – 2095 ● ●
9 Tools Model Workshop equipment 4 mm 5 mm 6 mm 8 mm 25 x 150 30 x 200 504 90 00-02 504 90 00-03 504 90 00-01 505 38 13-08 502 71 27-01 502 71 31-01 2036 ● – – ● – – 2040 ● – – ● – – 2041 ● – – ● ● – 2045 ● – – ● ● – 2050 ● – – ● ● – 2051 ● – – ● ● – 2054 ● – – ● – – 2055 ● – – ● – – 625 ● ● – ● – – 630 ● ● – ● – – 670 ● ● – ● – – 2077 – – – ● ● ● 2083 ● ● – ● ● ● 2094 ● ● – ● ● ● 2095 ● ● –
9 Tools Model Workshop equipment M6 M5 M4 502 51 67-01 502 50 88-01 502 50 87-01 502 50 86-01 502 51 54-01 Size 46: 108 07 21 46 48: 108 07 21 48 50: 108 07 21 50 52: 108 07 21 52 54: 108 07 21 54 56: 108 07 21 56 58: 108 07 21 58 2036 – – – ● – ● 2040 – – – ● – ● 2041 – – – ● – ● 2045 – – – ● – ● 2050 – – – ● – ● 2051 – – – ● – ● 2054 – – – ● – ● 2055 – – – ● – ● 625 – – ● ● ● ● 630 – – ● ● ● ● 670 – – ● ● ● ● 2077 ●
10 Technical data 10.
128 0.20 7.0 Oil pump capacity at 6000 rpm, ml/min 13–16 33–41 15.5 Bar length, inches Bar length, cm Chain speed at max. power, m/s – – Decompression valve 7–8 Silencer Crankcase 10–12 Cylinder 3–4 Carburettor Flywheel 2–3 25–30 Clutch Starter device 20–22 30–35 Plug Tightening torque, Nm .325 Chain pitch, inches Chain gear, number of cogs 0.40 2.0/2.0 Carburettor setting, H/L Oil tank, litres WT289 Carburettor, type Fuel tank, litres Walbro 0.
