ENGINE 500cc. 4T - 4V - H2O WORKSHOP MANUALS

Transcription

1 C ENGINE 500cc. 4T - 4V - H2O 4T WORKSHOP MANUALS 1 05/04

2 INTRODUCTION All checks, maintenance, repairs or replacements of spare parts in the vehicles manufactured by Malaguti are to be performed by skilled and expert technical personnel with specific experience in state-of-the-art technology and full knowledge of the quickest and most rational procedures, technical characteristics, setting values and tightening torques, information as to which may only be properly and exhaustively provided by the manufacturer. The present publication concerning four-stroke engines provides mechanics operating on Malaguti vehicles, whether working out of authorised service centres or self-employed, the essential information for operating in accordance with the latest Good Working Practices and Work Safety regulations. The present publication provides all necessary information for routine procedures on all the MALAGUTI motor vehicles equipped with four-stroke engines currently in production at the date of issue. The information provided deals with the MOTORS of the motor vehicle. Some basic technical information has been intentionally omitted as it is considered to be common knowledge. Additional information is available in the SPARE PARTS CATALOGUES of each model. It is important that before referring to the specific motor-bike manual, the information given in this general section be carefully read as it provides all the essential hints and guidelines for best consulting the various topics and main technical subjects. Note: the present manual provides the necessary information and instructions for the routine maintenance and servicing of Malaguti scooter engines. This information has been furnished to us by the engine manufacturers. Malaguti therefore declines all responsibility for any error, omission or misrepresentation. MALAGUTI reserves the right to make any changes and modifications hereto it deems necessary without prior notice. For further information and details, please contact Malaguti Servicing or Engineering Division. MANUAL UPDATE The up-date pages of this publication will be delivered by us (in due course) already punched and therefore ready for insertion in the Manual. The superseded sheets should not be removed from the manual as they remain applicable to the servicing of premodified models. The table of contents will be duly updated in case of the insertion of new pages causing difficulty in the rational consultation of the manual. IMPORTANT! The workshop manual is to be considered as an essential work instrument to be properly kept upto-date so as to maintain its validity over time. NOTES FOR EASY CONSULTATION PAGE LAYOUT X Engine model Y Section (chapter) W Page No. Z Date of issue X Y MODIFIED PAGES Modified pages shall bear the same number as those in the previous edition /pre-modified ones/ followed by the letter M, with the date of issue appearing in the appropriate box. Any modified illustrations shall bear the same numbers as the pre-modified ones followed by a letter. The picture which has been given a negative number (example F. 85 ), indicates that the previous numbers have been intentionally omitted. ADDITIONAL PAGES Any additional pages shall bear the last number of the section to which they belong followed by the letter A together with the date of issue. 2 05/04 W Z

3 EDITING SYMBOLS: Symbols have been provided for quick and easy reference, identifying situations requiring utmost attention or providing practical suggestions or simple information. These symbols may appear next to a text (in which case they refer solely to the text itself), next to a figure (in which case they refer to the topic illustrated in the figure and to the relative text), or at the top of the page (in which case they refer to all the topics dealt with in the page). Note: The meaning of the symbols should be duly memorised as their scope is to avoid having to repeat basic technical concepts or safety recommendations. They are therefore to be considered as veritable memory tags. In case of any doubt as to their meaning, consult the page in which they are fully described. CAUTION! Recommendations and precautions regarding rider safety and motor vehicle integrity. IMPORTANT! NO! Operations to be absolutely avoided. MECHANICAL MAINTENANCE. Operations to be performed only by an expert mechanic. ELECTRICAL MAINTENANCE. Operations be performed only by an expert electrical/ electronic technician. SPARE PARTS CATALOGUE. Indicates information which may be obtained by referring to said catalogue. GAUGE MEASUREMENTS MICROMETER MEASUREMENTS CENTESIMAL COMPARATOR MEASUREMENTS BORE METER MEASUREMENTS Abbreviations F Figure Cs Tightening torque P Page Pr Paragraph S Section Sc Diagram T Table V Screw Other symbols L O LOCTITE N... Molibdenum disulfite oil. Note - The operative symbols refer to assembling operations. M Engine oil. S Lithium-soap base grease. P Lithium-soap base grease. NEW Replace at each assembling. 3 05/04

4 GENERAL WORK PROCEDURES The advice, warnings and recommendations given hereafter are aimed at ensuring maximum work safety as well as at considerably reducing the risk of accidents, personal injury, equipment damage and idle times, and should therefore be strictly adhered to. ADVICE Only use quality tools and equipment. Only use equipment conforming to EU Directives for lifting the vehicle. During operations, always keep tools and equipment at hand, possibly laying them out according to the sequence in which they are to be used. Absolutely avoid putting them on the vehicle itself, out-of-sight or in poorly accessible places. Always keep the work area neat and clean. When tightening screws or nuts, start with the larger diameter or inner fasteners, and tighten them in progressive pulls using a criss-cross pattern. Preferably use open-end box wrenches by pulling and not pushing. Adjustable wrenches (F. 1) should preferably not be used as the movable jaw tends to open thus risking damaging or not properly tightening the bolt to the correct torque. Use only in case of emergency, i.e. when a properly sized box wrench is not available. In any case, when using an adjustable wrench, take care to proceed as shown in Figure 1. F. 1 WARNINGS Before carrying out any operation, turn off the engine, remove the ignition key and wait for all parts to cool down. For operations requiring two mechanics, make sure that the various steps to be performed by each of them are clearly defined and co-ordinated beforehand. Make sure that each component has been properly mounted before proceeding with assembling the next one. Lubricate all parts (where applicable) before reinstalling them. Always replace gaskets, O-rings, circlips and split pins at every refitting. The torque settings specified in the manuals refer to the final torque, which must be attained progressively by steps. Loosen and tighten aluminium alloy parts (covers) only after the engine has fully cooled down. Only use screwdrivers with sizes suitable to the screws to be loosened or tightened. Make sure that the vehicle is stable and not to have to take on awkward working positions. Never reuse old gaskets or circlips. Never use a screwdriver as a lever or chisel. Never use pincers to loosen or tighten screws or nuts because, in addition to not providing a sufficient clamping force, they may also damage the screw head or nut hexagon. Never tap the wrench with a hammer or other similar tool to loosen or tighten screws and nuts (F. 2). Never attempt to increase the lever arm by fitting a tube into the wrench (F. 3). 4 05/04

5 F. 2 F. 3 Never use open flames for any reason. Never leave open containers or containers not suitable for holding fuel in passageways, close to heat sources, etc. Never use petrol to clean the vehicle or the floor of the workshop. Always use low flash point solvents to clean the vehicle components. Never suck from or blow into the fuel pipe. When welding, make sure that there are no flammable liquids in the vicinity. Always remove the tank, even if completely empty, and disconnect the negative cable (-) from the battery. Never leave the engine running in closed or poorly ventilated areas. Before any servicing, make sure that the motor-bike is perfectly stable. The front wheel should preferably be anchored to the equipment integral with the lifting board. ENGINE REMOVAL For removal of the engine from the frame, refer to the cycle shop manual which lists all the operations required. ENGINE DISASSEMBLY The manufacturer declines all responsibility for damage of any kind caused by disassembly and reassembly of the engine and its parts if unsuitable tools ar used. Only use ORIGINAL MALAGUTI SPARE PARTS. 5 05/04

6 INDEX S CONTENTS P A General characteristics 8 B Special tools and torque wrench settings 9-10 Maintenance Spark plug 12 Engine oil C Transmission oil 14 Timing inspection 15 Valve clearance inspection/adjustment End of stroke compression pressure inspection 16 Automatic transmission Cover 17 External air conveyor Air conveyor filter 18 Air conveyor, transmission cover Timing belt antiflapping roller Driving pulley 19 Mobile driving semi-pulley 21 D Clutch bell Pipe pulley unit 22 Clutch disassembling Pins check collar 23 Fixed driven half pulley ball bearings Fixed driven half pulley 24 Mobile driven half pulley Mobile driven half pulley spring Clutch shoes 25 Driving belt Final reduction Reduction gear cap 26 Wheel axis and return shaft E Hub box ball bearings 27 Wheel axis ball bearing on the hub cover Intermediate shaft bearing on the hub cover Hub cover control 28 Hub shafts inspection Flywheel cover Coolant pump cap 29 Flywheel cover disassembling F By-pass flywheel cover components disassembling Stator 31 Lamellar valve Impeller 32 Flywheel and starting Starter 34 G Magneto flywheel Freewheel 36 Components inspection /04

7 S CONTENTS P Thermal unit and timing system Intake manifold 39 Tappet cover Timing system control device 40 Camshaft and rocking levers 42 Camshaft inspection 43 Further controls Head 44 Timing system components inspection Valves 47 Cylinder H Piston Pin inspection 48 Connecting rod small end inspection Piston inspection 49 Gas rings 50 Cylinder base gasket selection 51 Head inspection Cylinder inspection 52 Connections between piston and cylinder Valves inspection 53 Valve clearance inspection 54 Valve seats wear inspection Valves tightness test Washers, cotters inspection 55 Springs inspection Intake manifold I Injector 56 Throttle valve Motor case and driving shaft Motor case opening 58 Driving shaft removal Countershaft removal 59 Notes on reassembling Oil pump removal 60 Ball bearings replacement 61 Driving shaft controls L Driving shaft- case end float Driving shaft - connecting rod axial space 62 Driving shaft concentricity inspection Motor half casing inspection 63 Main bushing inspection 64 Countershaft control Oil pump inspection /04

8 MAIN 500 cc A FEATURES ENGINE Type:... 4-strokes Number of cylinders:... 1 Bore: mm Stroke: mm Piston displacement: cm 3 Compression ratio:... 10,5 : 1 Timing system:... flywheel side chain driven overhead camshaft; three-arm rocking lever with threaded register. Valves clearance :... suction: 0,15 mm. cold working... exhaust pipe: 0,15 mm. cold working motor idling ± 50 g/min air filter... sponge, impregnated with fuel mixture (50% fuel and 50% oil). CO Value % Valore CO% (idling, warm) ,5% Starting system... Electric starter with freewheel Lubrication... With pump (inside the case) Lubrication pressure... 4 bars Minimum pressure allowed (at 100 C)... 0,8 bars Supply... Electronic injection with electrical fuel pump, throttle valve Ø 38 mm and single injector Max. power allowed kw (39CV) at 7250 rev/min. Max. torque allowed N * m (4 Kg * m) at 5500 rev/min. Cooling system... with liquid, through a pump operated by the motor, three-way thermostat and electrical fan. Transmission... automatic variator with expanding pulleys, and torque server, V belt, automatic clutch, reduction gear and transmission space with cooling system by pump. Motor oil... ~ 1.7 litres (when dry) ~ 1.5 litres (when you change oil and filter) Rear hub... ~ 250 cc. Spark plug... NGK CR7EKB CHAMPION RG6YC Generator... alternate current, threephase generator 8 05/04

9 ATTREZZI SPECIAL SPECIALI TOOLS B Tool Description Notes Code Y Y Y009 Bell N Y010 N Y Y Y mm Y006 Pliers 15 mm Y mm Y mm Y034 Tool Description Notes Code Driven pulley spring compressor Adaptor 32x35 mm Y 24 mm Y Y 37 mm Y Driving shaft alignment support Y Flywheel extractor Y Punch Pin case punch Y Y Pin retainers assembling Y Adapter Guide 32x35 mm Y 37x40 mm Y 42x47 mm Y 52x55 mm Y 28x30 mm Y 12 mm Y 15 mm Y 17 mm Y 20 mm Y 25 mm Y 30 mm Y Countershaft timing pin Flywheel Stop Driving pulley stop Y Y Y009 Handle for adapters Valve cotters removal Y Y Piston position inspection Y Roller case assembling punch, driven pulley Extractor for valve oil retainer Oil pressure manometer union Y Y Y Countershaft stop Piston assembling fork Flywheel lock caliper wrench Y Y Y Magnetic base with comparator Y Case separation plate Y 9 05/04

10 B TORQUE WRENCH SETTINGS Particular Q.ty Torques (N * m) DRIVING SHAFT CASE Countershaft fastening nut Motor oil filter Motor oil drain plug Case connecting screws Gear screws on the driving shaft Oil pump compartment closure screws FINAL REDUCTION Hub cover screws TRANSMISSION COVER Driven pulley nut Driving pulley nut Transmission cover fasteners M Fastener M Antiflapping roller fastening Clutch ring nut Internal air conveyor screws Water pump cover screws External transmission cover screws Flywheel cover screws Transmission oil drain plug cap FLYWHEEL COVER Flywheel fastening nut Stator fasteners Blow-by recovery duct fastening screws Freewheel fastening screws on the flywheel Stator harness guide hanger screws Coolant pump impeller LUBRICATION Oil pump connecting screws 2 0,7 0,9 Oil pump fastening screws MOTOR UNIT Starter fasteners /04

11 B TORQUE WRENCH SETTINGS Particular Q.ty Torques (N * m) THERMAL UNIT AND TIMING SYSTEM Spark plug Head fastening stud bolts 4 *** Head fastening nuts Exhaust / intake head fastening nuts Head lubrication control jet Coolant temperature sensor Coolant temperature sensor support nut Counterweight mass fastening screw 1 7 8,5 Tightener shoe fastening screw Chain guide shoe retaining plate screws Stroke revolutions sensor fastening screw Injection fastening screw Valve lifter mass stopping bell fastening screw Intake manifold fastening screws Tappets cover fastening screws Throttle valve fastening screws Camshaft retaining brackets fastening screws Tightener fastening screws Tightener fastening central screw Head tightening screw Camshaft retaining brackets screws *** Operate first a torque wrench setting of 7 N * m in cross section sequence. Tighten of 90 in cross section sequence. Tighten again of 90 in cross section sequence /04

12 MAINTENANCE C SPARK PLUG Inspection each Km Replacement each Km Remove the spark plug while the engine is hot (taking utmost care to avoid scalding!). The carbon deposits and the colour of the insulator (around the central electrode) provide good information as to the heat range of the spark plug and to carburetion, lubrication and general condition of the engine. A light brown colour of (the insulator) indicates that engine working conditions are generally correct. Sooty black mat deposits, dry (to the touch), are a sign that working temperature is too low, i.e., that the heat range of the spark plug is too high, mixture too rich or ignition defective. A whitish colour of the insulator is indicative of too lean a mixture or of too low a heat range of the spark plug (i.e., spark plug too hot ). Check electrode gap (F. 4) (even if the spark plug is new) by means of a calibrated thickness gauge. If need be, adjust by acting only on the earth electrode F. 4 Advised spark plug: CHAMPION RG6YC NGK CR7 EKB ENGINE OIL Level inspection This operation has to be carried out when the motor is cold, following the here reported instructions: 1) Position the vehicle on its central stand and on a level ground. 2) Unscrew the dipstick/cap A, dry with a clean cloth and reinsert it, tightening it. 3) Remove again the dipstick/cap and be sure that the level is between the indexes Max and Min (F. 6); top up, if necessary. D A The reference of the MAX level shows a quantity of about 1700 cc of oil into the motor. Note - Should the control operations be carried out after having used the vehicle, that is to say when the motor is warm, the level line will be lower; in order to carry out a correct inspection, it is necessary to wait for at least 10 minutes after having stopped the motor. F. 5 D Oil top up The oil topping up, when necessary, should be carried out after the level inspection and, in any case, add oil up to the Max level; be sure never to pass this limit. The oil topping up from Min to Max requires about 400 cc. F. 6 A 12 05/04

13 C Oil and oil filter change Note - The engine oil has to be changed when the engine is warm. Remove the filler cap (A - F. 5). Drain the oil removing the drain (B - F. 7) Let that the oil flows into the appropriate container. Remove and clean the pre-filter (C - F. 9) with compressed air. Remove the cartridge filter by means of a wrench for filters (D - F. 5). Be sure that the O-rings (D - F. 9) of the pre-filter and of the drain plug are in good condition. Lubricate them and install again the pre-filter and the plug, tightening it to the specified torque. Install a new cartridge filter and do not forget to lubricate the O-ring before the installation; screw to the gasket contact point, tightening by hand. Pour the oil in the oil pan until it reaches the level between MIN and MAX. (the plug B is screwed tight). Close the oil filler plug (A - F. 5). Start the engine in order to load the filter and the lubrication system. Stop the engine and wait approx minutes. Reset the level to the MAX level. Oil used: SBK RACING 15W - 50 B F. 7 B F. 8 C F. 9 D 13 05/04

14 C TRANSMISSION OIL Level control Position the vehicle on a level ground and on its central stand. Unscrew and extract the oil dipstick (A), dry it with a clean cloth and reinsert it, tightening it. Extract again the dipstick, controlling that the oil level is between the indexes of MAX and MIN on the dipstick (F. 11); should the level be under the MIN notch, it will be necessary to restore the right quantity of oil into the hub. Screw again the dipstick, checking the tightening. A F. 10 A F. 11 Oil replacement Remove the oil filler cap (A). Arrange for an adequate container. Unscrew the oil drain plug (B) and let that the oil flows out completely. Screw again the oil drain plug with its relative gasket (C) and supply new oil. Screw again the oil filler cap. Oil used: ZC90 - SAE 80W90 C Prescribed oil quantity ~ 250 cc. F. 12 B B F. 12/a 14 05/04

15 C TIMING INSPECTION OF THE TIMING SYSTEM By means of a wrench, type TORX, remove the timing inspection cap, positioned on the flywheel cover. Remove the transmission cover and the relative soundproofing material. Rotate the driving shaft by means of the driving pulley, so that the reference point on the magnet support collimates with the one on the flywheel cover (PMS - F. 13). F. 13 Remove the head cover (F. 14). F. 14 Be sure that the reference point operated on the phonic wheel is aligned with the one operated on the head. Should the reference point be on the opposite side of the reference point operated on the head, make the driving shaft rotate once more. F /04

16 C VALVE CLEARANCE INSPECTION/ADJUSTMENT This control has to be carried out when the motor is cold. In order to carry out the inspection of the valves clearance, it is necessary that the timing reference points of the timing system collimate (see previous paragraph). Control, by means of a feeler gauge, that the clearance between the valve and the register corresponds to the indicated values. Should the values of the valve clearance, intake and exhaust, be different from those reported here following, proceed with their registration by loosening the counter nut (A) and operating with a screwdriver on the register (B). Intake work: 0,15 mm Exhaust work: 0,15 mm A B F. 16 COMPRESSION END PRESSURE INSPECTION This control has to be carried out when the motor is cold. Remove the spark plug cap. Remove the spark plug. Insert into the spark plug seat a compression gauge, by means of a 10 mm spark plug connector, at the right torque wrench setting: Connector to test compression: 10 N * m Disconnect the connector of the stroke revolutions sensor. Start the motor by means of the starter with the throttle valve fully opened, as long as the pressure gauge reading is stable. If the pressure is higher than 8 11 bars, remove the pressure gauge and proceed with the reassembling of the spark plug, of the cap and of the stroke revolutions connector. When the pressure values are lower than those indicated, check the engine revolution number at which the test is carried out; if lower than 450 rev/1', check the starting unit. Should the revolution number be the correct one, or slightly higher, proceed as follows: - Check the timing of the timing system - Check the valve clearance - Check the valve seal - Check the piston ring seal - Check the correct selection of the compression rate (cylinder base gasket) /04

17 AUTOMATIC TRANSMISSION D COVER Unscrew the four screws (A). Remove the cap (B). Remove the plastic cover (C). A 7 9 A B C F. 17 Unscrew the seven screws (M6). Unscrew the four screws (M8). Unscrew the fastening nut (D) of the driven pulley shaft, preventing the rotation of the shaft itself by means of a socket hexagonal wrench. M M8 M D M6 F. 18 Remove the nut (D), with the relative washers. Remove the transmission cover. D F. 19 Check that the transmission cover ball bearing rotates freely; should this not be the case, replace it. F /04

18 D EXTERNAL AIR CONVEYOR Unscrew the four fastening screws of the external air conveyor. F. 21 Remove the external air conveyor. F. 22 AIR CONVEYOR FILTER Unscrew the two fastening screws and remove the air conveyor filter (A). A F. 23 AIR CONVEYOR, TRANSMISSION COVER Unscrew the two screws (B) and remove the air conveyor (C). B C F. 24 B /04

19 D TRANSMISSION TIMING BELT ANTIFLAPPING ROLLER Control that the roller rotates freely (A) and that there isn t any sign of anomalous wear. If necessary, replace the roller with its bearing. B A F. 25 C V Unscrew the M8 screw (V). Remove the antiflapping roller (A). V A V F. 26 DRIVING PULLEY By a 27 mm wrench, turn the nut (C), so that the inner holes align horizontally, for the installation of the special tool: code Y009 First insert the retaining ring of the tool on the pulley, so that the slot (B - F. 25) fits well. Then insert the tool, so that the stud bolts on the ring fit well with the holes on the tool itself. Tighten (manually) the two tool fastening nuts. C C F. 27 Unscrew the nut (C). Remove the plain washer and the cone-shaped washer. Remove the fixed driving half pulley. C F /04

20 D Remove the washer on the bush. F. 29 Move the driving belt. Hold up the disk on which are leaning the rollers and extract the mobile driving semi-pulley with its relevant bush. Be careful not to cause the rollers discharging. F. 30 Extract the bush. F. 31 Remove the rear washer /04 F. 32

21 D MOBILE DRIVING SEMI-PULLEY Inspect the bush inner diameter (A). B A Ø standard: 30,021 mm Ø max. : 30,120 mm Inspect the pulley sliding bush (A) external diameter. Ø standard: 29,959 mm Ø min. : 29,950 mm F. 33 The rollers (B) have to be positioned as shown in the picture. The covered part must turn out to be the support on the inner pressure side of the rollers container. B Control that the rollers (B) are not damaged or excessively worn. Ø standard: 24,9 mm Ø min. : 24,5 mm F. 34 Control that the pads (C) of the plate (D) on which are leaning the rollers are not worn. Control furthermore the state of use of the rollers housing slots and the surfaces in contact with the driving belt, on both semi-pulleys. C D F /04

22 D CLUTCH BELL Removal Extract the spacer (A) and extract the clutch bell. A F. 36 Inspections Control that the clutch bell is not damaged or excessively worn. Control the inner diameter (B) of the clutch bell. B B standard : 160,2 mm B max. : 160,5 mm Maximum eccentricity value allowed: 0,2 mm. F. 37 DRIVEN PULLEY UNIT Extract the driven pulley unit, transmission belt included. F. 38 CLUTCH DISASSEMBLY In order to separate the clutch from the driven pulley, it is essential to use the special tools. Spring compressor - code Y F /04

23 D Prearrange the tool, with the median pins screwed in position E (reference point on the tool), on the inner side. Assemble the driven pulley unit on the tool, inserting the pins into the ventilation holes. Operate so that the setscrew fits well with the fixed driven pulley. F. 40 The tool has to be correctly secured within a vise and the central screw should be brought into contact with the tool itself. Too high a value of the torque may deform the special tool. By means of the specific 55 mm wrench, remove the fastening ring nut (G); then, disassemble the clutch unit. G mm wrench - code Y009 PINS RETAINING COLLAR Extract the collar, by using two screwdrivers. F. 41 G F. 42 Extract the four guiding pins. Extract the mobile driven half pulley. P F /04

24 D FIXED DRIVEN HALF PULLEY BALL BEARINGS Verify the total absence of damages and excessive wear. Remove the stop ring, using adequate pliers. A Support the pulley adequately, in order not to damage the thread. F. 44 By means of the special tool, inserted through the roller bearing, expel the ball bearings. Special tooling: Handle - code Y Adapter 24 mm - code Y 20 mm guide - code Y When replacing the bearings of a driven pulley assembly, it is necessary to support as follows: F. 45 Bell - code Y002 Overturn the pulley and, by means of the special tool, remove the roller bearing. Special tooling: Handle - code Y 25 mm guide - code Y Adapter 28 x 30 mm - code Y Bell - code Y002 FIXED DRIVEN HALF PULLEY Inspections Control if there is any sign of wear on the contact surface of the transmission belt. Verify the external diameter (A - F. 44). Ø standard: 49,965 mm Ø min. : 49,960 mm FIXED DRIVEN HALF PULLEY Inspections MOBILE DRIVEN HALF PULLEY Inspections Verify if there is any sign of anomalous wear on the contact surface of the transmission belt. Remove the o-rings, internal and external ones. Measure the inner diameter (B) of the mobile half pulley bush. B Ø B standard : 50,085 mm Ø B max. : 50,080 mm The O-Rings are of two different sizes. The biggest one is installed on the range of action at the base of the half pulley. F /04

25 D SPRING OF THE MOBILE DRIVEN HALF PULLEY Measure the free length (L) of the spring. L standard : 125,5 mm L min. : 120,0 mm F. 47 CLUTCH SHOES Control the thickness of the frictional material (A) of the clutch shoes. Minimum thickness allowed: 1 mm. A A F. 48 A The clutch shoes should not present any trace of lubricant. If any, accurately control the tightness of the driven pulley unit. During the running-in phase, the clutch shoes have to be subjected to homogeneous wearing (central contact surface). Different conditions might cause the sliding of the clutch. Do not open the clutch shoes with tools, in order to avoid a loading variation of the return springs. A F. 49 DRIVING BELT Should the driving belt present any damages, even the slightest one, replace it. Check the width (L) of the belt. L standard: 26,2 mm L min. : 25,0 mm F /04

26 FINAL REDUCTION E REDUCTION GEAR COVER Drain the oil from the rear hub, removing the cap (T - F. 54) positioned on the lower part of the engine. Use an appropriate container. Do not dispose of the oil in the natural environment. F. 51 Unscrew the seven fastening screws (V - F. 54) of the cover. F. 52 Remove the hub cover and the relative gasket. F. 53 NEW V V F. 54 T T /04

27 E WHEEL AXIS AND RETURN SHAFT Remove the return shaft and the wheel axis, together with its gear. F. 55 HUB BOX BEARINGS Verify the condition of the bearings: smoothness (anomalous frictions), noise during rotation, end plays. In case of malfunctions, replace the bearings by means of the special tools. Be careful not to lose or forget the centring bushes (A). As far as the removal of the bearing (wheel axis) on the engine case is concerned, use: Pliers 15 mm - code Y34 Bell - code Y031 B F. 56 A As far as the removal of the bearing (return shaft) on the engine case is concerned. use: Pliers 20 mm - code Y006 Bell - code Y035 As far as the removal of the bearing is concerned (driven pulley shaft), remove beforehand the Seeger ring (B). By means of the specific tools, remove the bearing of the driven pulley shaft from the engine case. Handle for punch - code Y Adapter code Y Guide 25 mm - code Y WHEEL AXIS BEARING ON THE HUB COVER Remove the Seeger ring from the external side of the hub cover /04 F. 57

28 E Support the hub cover, by using a stud bolts kit. Remove the bearing by means of the special tooling: Stud bolts Kit - code Y Handle - code Y Adapter 37 mm - code Y 30 mm guide - code Y Remove the oil retainer with a screwdriver (from the external side of the cover). F. 58 INTERMEDIATE SHAFT BEARING ON THE HUB COVER Support the hub cover, by using a stud bolts kit. Remove the bearing by means of the special tooling: Stud bolts Kit - code Y Pliers - code Y006 Bell - code Y007 INSPECTION OF THE HUB COVER Control that the coupling surface is not deformed or dented. In case of anomalies, replace the hub cover. HUB-SHAFTS CONTROL Verify that the three shafts are not excessively worn or deformed on the threaded surfaces and on the ball bearing/oil retainer coupling diameters (as shown by the letters in the different points). In case of anomalies, replace the damaged parts ) Return shaft 2) Wheel axis 3) Driven pulley shaft. 2 F. 59 Capacity diameter for return shaft: A = Ø 20-0,01-0,02 mm Capacity diameter for wheel axis: B = Ø 30-0,010-0,023 mm C = Ø 15-0,01-0,02 mm Capacity diameter for driven pulley shaft: D = Ø 17-0,01-0,02 mm E = Ø 20-0,01-0,02 mm F = Ø 25-0,01-0,02 mm F /04

29 FLYWHEEL COVER F Cut the clamps (A - B). Disconnect the two rubber sleeves, being careful not to damage the connectors. A NEW V6 F. 61 B NEW COOLANT PUMP CAP Unscrew the six fastening screws (V6) and remove the cap of the coolant pump. V6 3 4 F. 62 Note - if necessary, it is possible to remove the pump cap complete with its sleeves. F. 63 HUB COVER DISASSEMBLING Prepare an appropriate container. Unscrew the motor oil drain cap (S). S F /04

30 F Extract the precleaner (A). A F. 65 Unscrew and remove the motor oil filter cartridge (B), using a filter wrench. B F. 66 B Unscrew the 14 fastening screws (C) (the screws are of 4 different lengths. Take note of each position). Remove the flywheel cover with the relative gasket and the support for the rubber sleeves. NEW C C NEW F /04

31 F BY-PASS FLYWHEEL COVER COMPONENTS DISASSEMBLING Remove the by-pass (A) and the spring (B). Verify the absence of damages or scorings on the outer diameter of the by-pass (Ø 10,5 mm). Verify the free length of the spring (B): A B standard min. : 65,2 mm : 64,0 mm STATOR Unscrew the screws (V2) and remove the retaining bracket (C) of the harness. Unscrew the screws (V3) and remove the stator (D), complete with its harness. F. 68 D V3 V2 C V2 3 4 V Stator inspection Control the good condition of the stator and of the relative harness. Verify the continuity among the three phases and the mass insulation of each phase. (Resistance of each phase: 0,2 1 Ω). In case of anomalies, control the harness accurately. F. 69 LAMELLAR VALVE Unscrew the two fastening screws and remove the support of the lamellar valve with side wall. F. 70 Unscrew the fastening screw and extract the gas branch pipe, with the relative O-Ring. F /04

32 F Remove the blow-by lamellar valve, with its relative sealing gasket. F. 72 Be sure that the blade of the blow-by circuit, closes correctly. F. 72/a WATER PUMP IMPELLER Unscrew the coolant pump impeller from its relative shaft and remove it. A 4 5 There is a right-hand thread. It is necessary to prevent the rotation of the shaft, by inserting a 12 mm wrench in order to stop the shaft. F. 73 Extract the shaft with its relative washer. M F /04

33 F Verify that the coolant pump shaft does not present any sign of anomalous wear. F. 75 Verify that the impeller of the pump does not present any deformation or damage. Be sure that the plastic part is perfectly integral to the metallic part. F. 76 Remove the sealing ring (pump impeller side). F. 77 Remove the ceramic ring and the relative seal. In order to avoid damages to the ceramic seal, carry out the assembling manually. Accurately verify the lubrication ducts: the three channels of the by-pass, the water pump shaft oil feeding duct, the pump drain pipe, the feeding duct of the oil pressure sensor, the decantation chamber of the oil vapor. F /04

34 FLYWHEEL AND STARTING G Control that the cover of the coolant pump does not present any deformation or cracks. Before repositioning the pump cover, replace the O-Ring, paying attention that the latter does not enter into contact with lubricating agents. Note - Disassemble the flywheel cover as described in the previous paragraphs. F. 79 NEW STARTER Note - This operation can be carried out with the flywheel cover assembled. V Unscrew the fastening screws (V2) and extract the whole starter. V2 F. 80 MAGNETO FLYWHEEL Align the two holes on the magneto flywheel, with the housing on the case (seat A), so that to allow the insertion of the special tool: Stopping flywheel device - code Y A F. 81 Screw the stopping flywheel device bush on the thread destined to the extractor. F /04

35 G Insert the special tool, paying attention that the pins are inserted correctly into the holes previously aligned, on the magneto flywheel. B Do not insert the device pin (B), into the bearing, but be sure to insert it into the case seat (A - F. 81). Position the device correctly (it should be almost aligned with the flywheel). Insert the wrench into the device and unscrew the fastening nut of the magneto flywheel. Remove the special tool and the fastening nut. Flywheel fastening nut F. 83 Remove the washer. F. 85 Insert the specific extractor. With a wrench of 27 mm and one of 19 mm, unblock the magneto flywheel and extract it. V3 3 4 Flywheel extractor - code Y Unscrew the screws (V3) and remove the retaining plate of the chain guide shoe. F. 86 V /04

36 G Remove the key from its seat. F. 87 Remove the starting ring gear. F. 88 S Extract the intermediate gear, provided with the torque limiting device. F. 89 FREEWHEEL When disassembling the freewheel, it is advisable to loosen beforehand the six fastening screws, with the flywheel still assembled on the driving shaft. Unscrew the screws (V6). V6 V L 243 F /04

37 G The freewheel and the magneto flywheel are closely connected and their separation might be difficult. Screw two opposed screws to be used as grip, in order to facilitate the extracting operation. COMPONENTS INSPECTION Magneto flywheel Control: the integrity of the magnets. That the magnets support cage does not present any deformation or damages. That the riveted joints of the flywheel do not present any loosening. F. 91 M Freewheel Control that there isn t any sign of anomalous wear on the rollers. F. 92 Starting ring gear Control that there isn t any sign of excessive wear in the toothing and hub. B Check the diameter (A). Ø (A) = 45,665 Check the diameter (B). + 0, ,005 mm Ø (B) = , ,041 mm A F. 93 Anomalies occurring to the hub require the replacement of the starting ring gear and the freewheel; in case of excessive wear of the bearing brass only (B), it is only necessary to replace the starting ring gear. Control, in this case, also the driving shaft /04

38 G Intermediate gear and torque limiting device Verify the absence of anomalous wear to the toothing. Control the diameter (A) on both sides. -0 Ø (A) = 12 mm - 0,011 A Control also the diameter of the seats within the engine case and in the flywheel cover. F. 94 Ø ,034-0,016 mm Note - The torque limiting device is provided with four gears which operate as the driving disks of the clutch. The driven disks have been implemented with four grooved Belleville washers, allowing to transmit torques which are lower than 10 Kg * m. In case of wrong starting manoeuvres, the torque limiting device avoid counterstrokes, if any, with consequent reversal of rotation of the driving shaft, which might cause serious damages to the engine. The torque limiting device cannot be rebuilt; in case of anomalies, it is therefore necessary to replace it /04

39 THERMAL UNIT AND TIMING SYSTEM INTAKE MANIFOLD Unscrew the screws (V3) and remove the whole intake manifold unit. V V3 H F. 95 TAPPETS COVER Unscrew and remove the screws (V6) and the relative rubber seals. Remove the tappets cover and the relative gasket. F. 96 V6 Before reassembling the tappet cover, clean it accurately. Control the condition of the gasket and, if necessary, replace it. Once reassembled the tappet cover, tighten the screws (V6) (first the two screws shown in the picture with 1 and 2, then, in cross section sequence, the remaining four screws: 3-4, 5-6). V V6 3 F /04

40 H COMMANDE DE DISTRIBUTION Rotate the driving shaft so that to have the reference (A) in the position shown in the picture (closing point of the intake valves). Unscrew the central screw (V) and remove the stop bell of the valve lifter mass, by using the special tool. A V F. 98 V Special tooling: Caliper wrench - code Y F. 99 Remove the return spring, paying attention not to let it fall inside the motor. F /04

41 H Extract the valve lifter mass. Remove the stop washer, being careful not to make it fall inside the engine. F. 101 Align the three points of reference: A - B - C. F. 102 V Loosen the screw (V1) of the chain tightener. Unscrew the screws (V2) and remove the chain tightener with the relative gasket. V1 V1 5 6 V V2 F. 103 Unscrew the screw (V) and remove the counterweight. V 7 8,5 V F /04

42 H Remove the timing system chain gear. F. 105 Remove the phonic wheel (A). F. 106 Unscrew the fastening screw (V) and remove the phaserev. sensor and relative O-Ring ( NEW ). Remove the clamp from its hole on the head gasket. For the inspection of the phase-rev. sensor, please consult the Manual concerning the Injection. V 3 4 V F. 107 CAMSHAFT AND ROCKING LEVERS Unscrew the screws (V3) and remove the camshaft retaining bracket. V3 V3 4 6 F /04

43 H Extract the camshaft. F. 109 Remove the pins and the rocking levers, operating through the holes on the transmission side. F. 110 CAMSHAFT INSPECTION Verify there isn t any sign of anomalous wear or scorings on the surface of the camshaft. By means of a micrometer, measure the various diameters. Ø A standard : 42-0,060-0,085 mm Ø A min. : 41,910 mm Ø B standard : 20-0,020-0,041 mm Ø B min. : 19,940 mm F. 111 By means of a micrometer, verify the height of the cams. Inlet Exhaust (standard) : 33,988 mm (min.) : 33,740 mm (standard) : 33,417 mm (min.) : 33,170 mm End play (standard) : 0 0,22 mm (max.) : 0,30 mm Note - Verify there isn t any sign of anomalous wear in the groove (C). F /04

44 H FURTHER INSPECTIONS Verify that there isn t any sign of wear on the automatic valve lifter cam, on the counterweight, on the stop roller and on the rubber beat of the retaining bell. Be sure that the valve lifter spring is not yielded. Finding out worn pieces, replace them. F. 113 Verify that the pins of the rocking levers do not present any sign of excessive wear or scorings. Verify the internal diameter (A) of the rocking levers. - 0,010 Ø standard pin : 13 mm - 0,018 internal Ø A : 13 mm + s0, ,015 Verify that there isn t any sign of wear on the contact surface of the shoe (B) with the cam and on the pans (C) of the registers. In case of excessive wear, replace the component. F. 114 HEAD Remove the temperature sensor (S) of the coolant. S Note - For the inspections to carry out on the temperature sensor, please consult the Manual concerning the Injection. S Cut the fastening clamp (A) or coupling. Remove the outlet coupling of the coolant system, complete with its thermostat (T). F. 115 NEW A F /04

45 H Unscrew the fastening nut (A). A F. 117 A Unscrew the fastening nut (B). B F. 118 B Unscrew the two nuts (C - M6) and the nut (D - M6), complete with its thermostat support. 4 1 E C D Loosen (repeatedly and in cross section sequence) the four stud bolts (E) for the head-cylinder connection. C D During the reassembling operations, please see the following instructions: - Screw the four stud bolts in cross section sequence, as shown in the picture, at the torque of 7 N * m. Tighten of a 90 angle the four stud bolts, always in the sequence shown in the picture. - Tighten of further 90, always in the sequence shown in the picture. Cs E 7 N * m F /04

46 H Extract the head unit with the utmost care. Note - In this phase, provide for an adequate container for the coolant container inside the thermal unit. F. 120 Remove the head gasket (G). It is a steel-made gasket and its thickness is a standard one. NEW G F. 121 Unscrew the fastening screw (V) of the chain tightening shoe. V V F. 122 Extract the chain tightening shoe, the chain guide shoe and the chain itself. Mark the chain, in order to guarantee the original rotation way. F /04

47 H TIMING SYSTEM COMPONENTS INSPECTION Verify that the guide shoe and the tightening shoe are not excessively worn. Control that there isn t any sign of wear on the timing system gear unit which controls the camshaft and the driving shaft pinion. Finding out that the shoes are worn, replace them, or should the chain or gear be worn, replace the whole unit. Note - Should the chain cause damages to the pinion, it is necessary to replace the driving shaft, operating as described within the chapter Case and shaft. F. 124 VALVES By means of the special tool, complete with its adapter, disassemble the cotters, the pans, the springs. Tool for the removal of valves - code Y Adapter - code Y012 F. 125 Lay down the valves so that to remember their original position on the head (flywheel side and transmission side). Remove the oil retainers by means of the special tool: Extractor for oil retainers - code Y Remove the spring supports, by injecting compressed air into the housings, in order to facilitate the removal operations. CYLINDER Extract the cylinder (with care), the relative basket and the dowel. Support the piston during the removal of the cylinder, in order to avoid damages. NEW NEW F /04

48 H PISTON Remove the two stop rings (A) of the piston pin, operating through the specific slots. Extract the piston pin and remove the piston. Occlude the piston housing (B) with paper or a cloth, in order not to make accidentally fall the stop rings of the piston pin or other objects inside it. B F. 127 A Remove the piston pin from the piston. F. 128 Take note of the original position of the piston ring seals, so that not to make mistakes during reassembling operations. Remove the O-rings and the scraper rings of the piston. Do not damage the O-rings during the disassembling operations. F. 129 PISTON PIN CONTROL Check the outside diameter of the piston pin. Ø standard : ,004 mm F /04

49 H CONNECTING ROD SMALL END INSPECTION Measure the diameter (A) of the connecting rod small end. Ø A standard : , ,015 mm A Finding out a higher diameter, replace the connecting rod. Note - Clearance (standard) between connecting rod small end piston pin : 0,015 0,029 mm. F. 131 PISTON INSPECTION Measure the diameter (B) of the pin seat, on the piston. Ø B standard : , ,001 mm The measuring of the diameter has to be carried out in accordance with the axis of the piston. F. 132 The pin housings have two lubrication ways. F. 133 Note - Accurately clean the housing of the sealing rings. Verify, by means of a thickness gauge, the clearance (E) between the O-rings and the slots of the piston. Finding out higher clearance values than those shown in the table reported here following, replace the piston. E 1 Compression 2 Compression Scraper ring F /04

50 H Measures (mm) Segmenti O-rings 1 Compression A = 0,9-0, ,003 C = 0,9-0, ,010 B = 1,5-0, ,05 D = 2-0,030-0,02 2 Compression 12-0,005 12,5 + 0,03 Scraper ring 2,5-0,005 2,5 + 0,03 F. 135 SEAL RINGS Note - Insert the three piston ring seals in the area of the cylinder where the original diameter is maintained. The insertion should be an orthogonal one (at this purpose use the piston). Measure the fissure (opening) (E), of the rings, by means of the thickness gauge. Finding out higher values than those shown in the table reported here following, replace the components (piston ring seals). E (mm) Piston rings Standard Max. Compression 0,15 0,35 0,50 Scraper ring 0,25 0,50 0,65 F. 136 Assembly Note - The 2 seal segments are made with a cylinder conical contact surface in order to reach a better setting. The 1 compression piston ring seal has an L section. Lubricate the parts with motor oil and use a insertion special tool, in order to facilitate the assembling of the piston ring seals. M F. 137 Position the spring of the scraper ring on the piston. Install the scraper ring with the opening opposite to the spring joint and the top writing facing the piston crown. In any case, the machining chamfering has to be positioned towards the piston crown. Install the 2 seal segment with the identification letter or the top writing facing the piston crown. In any case, the working step has to face the part opposite to the piston crown. Install the 1 seal segment with the top writing or the reference mark facing the piston crown. Stagger the segment openings at 120, as shown in the picture /04 F. 138

51 H CYLINDER BASE GASKET SELECTION Install temporarily the cylinder on the piston, without the base gasket. Install a test indicator on the special tool, using the short coupling device, as shown in the picture. Special tooling: Support to check the piston position - code Y F. 139 By means of a surface plate, reset the comparator with a preloading of some millimetres. Fasten the comparator correctly. Verify the correct sliding of the feeler pin. Assemble the tool on the cylinder, without changing the position of the comparator. Fasten the tool by means of the head fastening original nuts. Rotate the driving shaft until the P.M.S. (comparator s rotation reverse point). Measure, on the comparator, the deviation from the reset value. By means of the here reported table, identify the thickness of the cylinder-base gasket to use for the reassembling. The correct identification of the cylinder-base gasket thickness leads to the maintaining of the correct compression ratio. Remove the specific tool and the cylinder. F. 140 Note - In case of deviations (protrusions or recesses) almost in the proximity of the category change, repeat the measuring from the opposite side. Repeat the device assembling by inverting its position. The measure A (without gasket) is a piston recess value; it indicates how much the surface, formed by the crown of the piston, goes down with respect to the surface, formed by the advanced part of the cylinder. The more the piston descends inside the cylinder, much lesser will be the S thickness of the base gasket to apply (in order to restore the correct compression ratio), and vice versa. R = Recess S = Projection A S R/R - 0,185-0,10 0,4 ± 0,05 R/S - 0,10 + 0,10 0,6 ± 0,05 S/S + 0,10 + 0,185 0,8 ± 0, /04 F. 141

52 H HEAD INSPECTION By means of a ground bar and thickness gauge, verify the flatness of the head base. max. tolerance allowed: 0,1 mm Then verify the bases of the manifolds: Intake and exhaust. Finding out anomalies, replace the head. F. 142 CYLINDER INSPECTION Measure the internal diameter of the cylinder (orthogonally and at three different heights). Ø standard : , ,010 mm F. 143 Indication of the three heights at which is necessary to carry out the measuring of the cylinder diameter (F. 144) Verify that the covering is not damaged or that there isn t any trace of scaling. Verify the flatness of the connection plane surface with the head. max. tolerance allowed: 0,05 mm F /04

53 H PISTON AND CYLINDER COUPLING Measure the external diameter (E) of the piston at the height reported in the picture. F. 145 Measure the internal diameter (F) of the cylinder at the height reported in the picture. Note - Pistons and cylinders are classified into categories; in function of the diameter, the coupling has to be carried out in function of equal diameters: (A - A / B - B / C - C / D - D). Coupling category Name Cylinder Piston Assembling clearance A 91,990 91,997 91,947 91,954 B 91,997 92,004 91,954 91,961 C 92,004 92,011 91,961 91,968 D 92,011 92,018 91,968 91,975 0,036 0,050 F. 146 VALVES CONTROL Control the conservation condition of the sealing surface (A) of the valves; discontinued or bent surfaces require the replacement of the valves. Do not change the assembling position of the valve (right - left). F. 147 Verify the diameter of the valve stems, at the three points shown in the picture. (mm) Valve Ø Standard Ø min. Intake work 4,987 4,972 4,96 Exhaust work 4,975 4,960 4, /04 F. 148

54 H By means of a concentricity support, verify the linearity (deviation, if any) of the valve stems. Max.: 0,01 mm F. 149 Rotate the valve and verify the perfect concentricity of the head. Limit allowed: 0,03 mm F. 150 Control the wearing condition of the part in contact with the registers articulated terminal. Valves standard length Intake work : 95,0 ± 0,3 mm Exhaust work : 94,2 ± 0,3 mm F. 151 VALVE RADIAL CLEARANCE CONTROL Measure the inner diameter of the valve guides and verify the clearance with the stems previously measured. RADIAL CLEARANCE (mm) Valves Standard MAX. Intake work 0,013 0,04 0,08 Exhaust work 0,025 0,052 0,09 F /04

55 H INSPECTION OF THE WEAR OF THE VALVE SEATINGS Accurately clean the valve seats from any carbon residuals. Through the Prussian blue, control the impression on the V valve seat. Take down all measurements taking into account the direction of the rocking lever thrust, at three different levels. V standard : 1 1,3 mm V max. : 1,6 mm F. 153 In case the impression width values on the valve seat are higher than the expected limit values, rectify the seats with a milling cutter at 45 and grind. In case of excessive wearing or damages, replace the whole head unit. VALVE TIGHTNESS TEST Insert valves in the head. Test alternatively inlet and exhaust valves. This test has to be performed filling with gasoline the manifold and checking that the head does not bleed from the valves, holding them pressed only with the fingers. F. 154 F. 154/a CAPS, COTTERS CONTROL Check that the superior support caps of the springs and the cotters do not show unusual wears. F. 155 SPRINGS INSPECTION Measure the free length (L) of the springs. L - standard : 44,4 mm L - min. : 42,4 mm 55 05/04 F. 156

56 INJECTOR INTAKE MANIFOLD I The injector has to be removed exclusively in case we are sure of its malfunction. The operative tests have to be carried out with the injector assembled on the manifold. V Unscrew the central screw (V). Extract the injector from the manifold. F. 157 F. 158 V THROTTLE VALVE The throttle valve is supplied complete with all its components. V3 Unscrew the screws (V3). F. 159 The throttle valve is pre-set by the manufacturer. Therefore avoid any intervention on the valve register controlling the opening and closure of the throttle valve itself, which has been appropriately sealed for the idle adjustment. Please consult the Manual concerning the Injection. Accurately clean with a compressed air jet the gas valve and the relative pipe. F /04

57 I Then clean the supplementary air pipe, controlled by the stepper-motor. F. 161 Verify the good condition of the tightening lips on the coupling level surfaces between manifold-throttle valve and between manifold-head. Air leaks, if any, might prejudice the functionality of the injection system, in particular when the motor is idling. Note - After the replacement of the throttle valve, if necessary, proceed with the T.P.S. reset and the adjustment of the CO%. F. 162 V 3 4 V NEW P L 243 V3 V NEW NEW F /04

58 CASING AND DRIVING SHAFT L Before proceeding to the opening of the motor case, it is necessary to verify the end float of the shaft, using the special tooling: Crankcase separation plate - code Y Magnetic base with test indicator - code Y Standard play Play max. : 0,10 0,50 mm : 0,60 mm OPENING OF THE ENGINE CRANKCASE Unscrew and remove the 14 case connecting screws. Note - The fastening screws are of three different lengths. Take note of the reassembling sequence. V F. 164 Separate the cases, keep the driving shaft in position on the half-case, flywheel side. Remove the connection gasket. NEW DRIVING SHAFT REMOVAL Before removing the driving shaft, verify the timing with the countershaft: rotate the driving shaft until you obtain the alignment between the two holes on the driving shaft with the hole present on the control gear of the countershaft. F /04 F. 166

59 L Remove the driving shaft with the shim adjustment washer (A), flywheel side. During the removal of the driving shaft, be careful that the threaded parts do not enter into contact with the bench bearing brasses. F. 167 COUNTERSHAFT REMOVAL Fasten the special tool on the two threaded holes of the case. F. 168 Special tool: Countershaft stopping wrench - code Y F. 169 On the opposite side of the case, unscrew and remove the fastening nut and the relative washer. Nut Remove the special tool and extract the countershaft complete with control gear. M 59 05/04 F. 170

60 L REASSEMBLING NOTES P P L 243 P P F. 171 OIL PUMP REMOVAL Unscrew the screws (V2) and remove the case which closes the oil pump compartment. V V2 F. 172 Unscrew the two screws (V) (through the gear eyelets). Extract the oil pump, complete with its gear. V 5 6 V 60 05/04 F. 173

61 L Remove the gasket of the oil pump. NEW F. 174 BEARINGS REPLACEMENT Verify the correct smoothness of the bearings and the absence of noise, frictions and anomalous wear. Otherwise, proceed with their replacement. On the other side of the half case (flywheel side), remove the bearing, by using the special tool and a fibre mallet. Special tooling: Adapter handle - code Y F. 175 Adapter 37x40 code Y 17 mm guide - code Y Remove the bearing from the half case, transmission side. Before assembling a new bearing, heat the half case (with an electrical heating gun), flywheel side. Position the half case on a wooden level surface. P Always grease the bearings seats, before their installation. Note - The bearings with a plastic cage have to be assembled with the balls turned towards the internal side of the case. DRIVING SHAFT INSPECTIONS By means of a concentricity control support, control the end float (A) of the connecting rod (0,20 0,40 mm). Control the radial clearance (B) of the connecting rod (0,046 0,076). F /04

62 L DRIVING SHAFT - CASE END FLOAT Standard clearance (A): 0,1 0,5 mm (cold). DRIVING SHAFT - CONNECTING ROD Standard size of the compartment (B): 22-0,10-0,15 mm A B F. 177 DRIVING SHAFT CONCENTRICITY INSPECTION Position the shaft on the concentricity control support; measure the misalignment, if present, in the four reference points shown in the picture. Max. eccentricity value allowed (mm) A = 0,15 B = 0,01 C = 0,01 D = 0,10 F. 178 Verify the good condition of the driving shaft at all reference points pointed out in the picture. Note - In case of anomalies, replace the driving shaft. The diameters of the bench bearers cannot be grounded. The connecting rod cannot be replaced singularly. F /04

63 L During the washing and cleaning operations of the driving shaft, verify that are not inserted, into the lubrication hole (A) of the driving shaft, foreign matters or simple contraries. In case of replacement of the driving shaft, composed by two half shafts of different category, it is also necessary to replace the two half cases, pairing the shaft and the case of the same category. F. 180 Verify the width (L) of the driving shaft, being careful that the measure taken, has not been changed by the radiuses. L standard: 63,45 63,60 mm F. 181 ENGINE HALF CASE INSPECTION Clean, first thing, all the surfaces and all the lubrication pipes. In the half case, transmission side, operate in particular on the bench bearing brasses, on the cooling jet (J) and on the lubrication pipe. Note - The jet (J) is supplied by the bench bearing brasses. The correct working of this component improves the cooling of the piston crown. Its occlusion might determine negative effects, which are really difficult to be detected (increase of the piston temperature). Losses or leaks may drastically lower the lubrication pressure to the bench bearing brasses and to the connecting rod. F /04

64 L For the half case, flywheel side, pay the utmost attention to the lubrication pipes of the bench bearing brasses, to the compartment and to the pipes of the oil pump and to the by-pass pipe (B) located on the flywheel cover. Note - As already described in the lubrication chapter, it is extremely important that the by-pass housing does not show any wears, which may compromise a good seal of the piston adjusting the lubrication temperature. The duct for the head lubrication is equipped with a shutter jet: this causes a head lubrication of the low pressure type; this choice has been made in order to contain the oil temperature in the oil pan. F. 183 The jet occlusion compromises the head lubrication and the timing mechanism. The lack of the jet results in a reduction of the lubrication pressure both of the journal brasses and of the connection rod. Check that the levels do not show any dents or deformations, paying particular attention to the cylinder-crankcase levels and to the casing coupling. A possible defect of the crankcase or levels coupling gasket may cause a leakage of the oil under pressure, damaging the lubrication pressure of the journal brasses and of the connection rod. Check that the containment surfaces of the driving shaft end play do not show any wear. To perform the dimensional check, refer to what explained for the checks of the end play and the dimensions on the driving shaft. JOURNAL BRASSES INSPECTION In order to obtain a good lubrication of the journal brasses, it is necessary to have both an excellent lubrication pressure (4 bar) and a good oil capacity; it is essential that the bearings are positioned correctly, so as to avoid chokings of oil feeding holes. Journal brasses are made by 2 half bearings, one solid and one with holes and slots for the lubrications. The solid half bearing supports the thrusts due to the combustion, therefore it is positioned opposite the cylinder. In order to avoid chokings of the oil feeding holes, the coupling level of the two half bearings has to be perfectly orthogonal to the cylinder axle. The section of the oil feeding holes is also influenced by the driving depth of the brasses, as to the containment level of the driving shaft end play. Note - To keep such position of the brasses on the crankcase, the driving has to be forced on steel rings cast-in in both half casings. Check the brasses diameter in the 3 directions shown. Repeat the measurements for the other half of the brass. Avoid the measurements on the coupling level of the 2 half bearings, avoid measurements on the connection level surface of the two half bearings, in fact the ends can be adjusted so that to allow a deformation during the driving. The standard diameter of the brasses after the driving may vary according to a coupling selection. The seats of brasses in the crankcase are classified in 2 categories as for the driving shaft: Cat. 1 e Cat. 2. Brasses are divided in 3 categories according to the thickness; see the here reported table. F. 184 TYPE IDENTIFICATION THICKNESS A Red 1,982 1,987 B Blue 1,987 1,992 C Yellow 1,992 1, /04

65 L COUNTERSHAFT INSPECTION Measure the diameters (A - B) of the countershaft. Ø standard: 17-0,01-0,02 mm Verify that there isn t any sign of excessive wear to the water pump dragging device. OIL PUMP CONTROL Remove the screws (V2) and the oil pump cap. F. 185 V2 0,7 0,9 V2 Remove the snap ring for the retaining of the internal rotor; rotate it until you take the opening in correspondence with the cut-off of the spindle. Remove the rotors, carrying out an adequate cleaning with petrol and compressed air. Extract the spindle with its gears; verify its good conditions and possible wearing on the spindle itself. Reassemble the rotors with the pump unit, so that the two reference points are well in sight. Insert the spindle with gears, install the sealing ring and rotate it, paying attention to keep the opening on the other side of the spindle cut-off. Control if there is any anomalous clearance between spindle and pump unit. M F. 186 F. 187 By means of a thickness gauge, control the distance (A) existing between the rotors. Limit clearance allowed: 0,012 mm Control the distance (B) existing between the external rotor and the pump unit. Limit clearance allowed: 0,25 mm Control the axial clearance of the rotors, using a rectified bar as reference surface. Limit clearance allowed: 0,1 mm 65 05/04 F. 188