SV150 by WORKSHOP MANUAL Rel. 1.0 - 01/2005 The manufacturer reserves the right to make all the necessary technical or commercial improvements to its products, so there may be some differences between the series of lawnmowers and the contents of this manual. However the basic specifications and different operating procedures will remain the same.
<= ...BACK... <= WORKSHOP MANUAL i.0 TABLE OF CONTENTS MAIN CHAPTERS SV 150 2004 to •••• page 1 / 1 from ening torques, expendable materials and spare parts available. 1. Rules and procedures for Service Centres This chapter covers all the main aspects of the relationship between the manufacturer and the service centres.
WORKSHOP MANUAL <= ...BACK... <= SV 150 ii.0 INTRODUCTION 2004 to •••• page 1 / 1 from INTRODUCTION The purpose of this manual is to help Service Centres service, disassemble and repair SV150 engines. Each page of this manual states the following information: G B G WORKSHOP MANUAL C from 2004 to •••• 1/2 page F 6.
<= ...BACK... <= WORKSHOP MANUAL 1.1.0 RULES AND PROCEDURES FOR SERVICE CENTRES SV 150 2004 to •••• page 1 / 1 from 1.1 RULES AND PROCEDURES FOR SERVICE CENTRES A) Warranty validity The warranty is supplied under the terms, procedures and limits stated in the contract. B) Post-warranty assistance The Service Centre is obliged to compile a report for every service, stating the engine serial number[ 3.1.A], the summary of claims, the operation carried out and any spare parts used.
<= ...BACK... <= WORKSHOP MANUAL 2.1.0 GENERAL AND SAFETY REGULATIONS 2.1 GENERAL AND SAFETY REGULATIONS A) Qualification of operators All maintenance, disassembly and repairs must be carried out by expert mechanics who are familiar with all the accident prevention and safety regulations after reading through the procedures in this manual. B) Safety measures All the engines are built in conformity with the European safety regulations in force.
<= ...BACK... <= WORKSHOP MANUAL 3.1.0 TECHNICAL DATA AND SPECIFICATIONS A) Identification All the engines have a serial number stamped on the right-hand side of the crankcase; this 9figure code identifies: • - ••• - ••••• Year of manufacture Date Daily progressive number The serial number must be reported on every operating sheet in the warranty application and is fundamental for identifying and ordering spare parts. B) Technical data Piston displacement ....................................
WORKSHOP MANUAL <= ...BACK... <= 3.1.0 TECHNICAL DATA AND SPECIFICATIONS G) Spare parts Below is a list of spare parts available, not including parts that are easily available or whose replacement would entail particularly expensive assembly and disassembly operations. To order a spare part, refer to the code on the exploded view regarding the year of manufacture.
<= ...BACK... <= WORKSHOP MANUAL 4.1.0 ENGINE TUNING AND TESTING 4.1 ENGINE TUNING AND TESTING A) Operating guidelines The instruction manual describes a series of operations for the client to ensure minimum basic maintenance. For operations beyond the client’s capability, the Service Centre should see to keeping the engine in perfect working order by: – Tuning the engine whenever possible. – Recommending the client a routine maintenance program at set intervals (e.g.
<= ...BACK... <= WORKSHOP MANUAL 5.1.0 TROUBLESHOOTING SV 150 2004 to •••• page 1 / 5 from A) The engine does not start Probable cause Comment Solution Lawnmower problems The cable control does not activate the coil earth switch. Adjust and/or replace the cable [ 6.7.A] The microswitch is faulty If the microswitch remains locked in the pressed position, it does not stop the coil earth connection. Replace the microswitch [ 6.7.
WORKSHOP MANUAL <= ...BACK... <= 5.1.0 TROUBLESHOOTING SV 150 2004 to •••• page 2 / 5 from Carburation problems Carburettor is dirty If the jet and the pipes inside the carburettor clog up, the petrol flow drops and the engine fails to function correctly. Check and clean the carburettor [ 6.4.A] Poor seal of carburettor needle valve If the needle valve does not close, excess fuel in the float chamber can reach the combustion chamber through the intake manifold.
WORKSHOP MANUAL <= ...BACK... <= 5.1.0 TROUBLESHOOTING SV 150 2004 to •••• page 3 / 5 from chamber, the engine stops. After a few minutes, the float chamber fills up and the engine is able to restart, only to stop soon after. Fuel filter clogged Inside the tank, the filter has a metal mesh which can clog up with dirt or with a film of old fuel. Empty and clean the tank [ 6.1.
WORKSHOP MANUAL <= ...BACK... <= SV 150 5.1.0 TROUBLESHOOTING 2004 to •••• page 4 / 5 from Environmental problems The engine is used at a high altitude The rarefaction of air in the mountains causes a drop in power of approx. 10-12% every 1000 metres of altitude. Advise your client to adapt the strain of the lawnmower to the limited power available.
WORKSHOP MANUAL <= ...BACK... <= 5.1.0 TROUBLESHOOTING SV 150 2004 to •••• page 5 / 5 from Electrical problems The earth cable is disconnected or broken The broken or disconnected cable prevents the microswitch from closing the electric circuit to earth Check the earth connection [ 6.7.B] J) The engine judders Probable cause Comment Solution Blade not balanced The imbalanced or loose blade causes judders and the premature wear of all the parts inside the engine.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.1.0 TANK AND SUPPLY 2004 to •••• page 1 / 2 from 6.1 TANK AND SUPPLY GENERAL INFORMATION The supply system consists of a petrol tank (built into the upper conveyor) connected to the carburettor by a pipe. A mesh filter on the bottom of the tank stops deposits and impurities from reaching the carburettor.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.1.0 TANK AND SUPPLY 2004 to •••• page 2 / 2 from reverse order. WARNING! Check that the petrol pipe (4) is intact and secured correctly before pouring in new fuel. 5 B) Cleaning the tank 11 Remove the conveyor (1) secured by three nuts (2). 4 12 Remove the ring (5) from the tank side, disconnect the petrol pipe (4) and drain all the fuel from the tank into a suitable container.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.2.0 STARTING SYSTEM 2004 to •••• page 1 / 3 from 6.2 STARTING SYSTEM GENERAL INFORMATION The starting system is built into the upper conveyor (which also includes the tank) and consists of a cable wound onto a pulley. The movement from the pulley to the flywheel (and the engine shaft) is transmitted by a pair of hooks. The cable is returned and rewound by a spiral spring.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.2.0 STARTING SYSTEM 6 Fit the other end of the cable in the conveyor hole, securing it to the handle (5) with a knot. 7 Turn the pulley (3) and the cable (4) anticlockwise for approx. 5 complete revs to load the spring, then release the pulley carefully to wind the entire cable onto the pulley. 8 Check that the pulley (3) is free to rotate.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.2.0 STARTING SYSTEM 2004 to •••• page 3 / 3 from 33 If the spring is not already released, keep hold of the pulley (3) and slowly unwind the entire cable (4) clockwise to release the return spring gradually. 34 Dismount the hooks [ point “B”]. 9 35 Remove the pulley (3), making sure that the return spring (9) stays in place underneath the pulley.
<= ...BACK... <= WORKSHOP MANUAL 6.3.0 INTAKE SYSTEM SV 150 2004 to •••• page 1 / 2 from 6.3 INTAKE SYSTEM GENERAL INFORMATION The intake system uses an air filter which is directly connected to the carburettor and a manifold which conveys the air/petrol mixture towards the induction valve. The intake system can malfunction in the following ways: • no or difficult starting or insufficient power (if not due to other causes): = Air filter clogged [ 6.3.
<= ...BACK... <= WORKSHOP MANUAL 6.3.0 INTAKE SYSTEM SV 150 2004 to •••• page 2 / 2 from B) Removing the filter body 11 Clean the area around the filter cover (1). 12 Remove the cover (1) by releasing the rear flap (2) and take out the sponge filtering element (3). 2 13 To remove the filter body (5), loosen the screw (7) fastening the governor system bracket and the two screws (8), remembering that both these screws also fasten the carburettor to the engine block.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.4.0 CARBURATION 2004 to •••• page 1 / 3 from 6.4 CARBURATION GENERAL INFORMATION The carburettor has a float with a fixed jet and a “CHOKE” control. The carburettor can malfunction in the following ways: • difficult or failed start or insufficient power (if not due to other causes): = Carburettor dirty [ 6.4.A]. • engine runs irregularly (if not due to other causes): = Air has seeped into the carburettor [ 6.4.A].
<= ...BACK... <= WORKSHOP MANUAL 4 SV 150 6.4.0 CARBURATION 2004 to •••• page 2 / 3 from Loosen the central screw (5) fastening the float chamber (6) and carefully collect all the petrol left in the float chamber. 10 5 Pull out the pin (7), dismount the float (8) and remove the gasket (9). 11 6 Undo the screw (10) and pull out the jet (11). 10 9 7 Clean the jet and the carburettor thoroughly by immersing them in clean petrol (or a detergent) for 24 hours.
<= ...BACK... <= WORKSHOP MANUAL 6.4.0 CARBURATION SV 150 2004 to •••• page 3 / 3 from C) Adjusting minimum speed 21 Check that the throttle cable is adjusted correctly [ 6.5.A]. 22 Let the engine heat up for a few minutes, then set the throttle control to “SLOW”. Check the rotation speed on the speed indicator (21). 21 NOTE The engine’s minimum speed must be between 2200 and 2500 rpm.
<= ...BACK... <= WORKSHOP MANUAL 6.5.0 GOVERNOR SYSTEM OF THE CARBURETTOR SV 150 2004 to •••• page 1 / 3 from 6.5 GOVERNOR SYSTEM OF THE CARBURETTOR GENERAL INFORMATION The carburettor’s governor system consists of a lever system mounted on a support attached to the engine’s cylinder head, with a built-in pneumatic device. This device consists of a fin disc which tends to close the carburettor’s choke under the pressure of the flywheel air, against the main spring of the control lever.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.5.0 GOVERNOR SYSTEM OF THE CARBURETTOR 2004 to •••• page 2 / 3 from B) Adjusting maximum speed 11 Check that the throttle cable is correctly adjusted [ point “A”]. 12 Let the engine heat up for a few minutes then set the throttle control to “FAST”. Check the rotation speed on the speed indicator (21). 21 NOTE The engine’s maximum speed must be between 2800 and 3000 rpm; if you do not read this value, proceed as follows.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.5.0 GOVERNOR SYSTEM OF THE CARBURETTOR 2004 to •••• page 3 / 3 from element (32), then loosen the screw (33). 23 Loosen the three screws (34) fixing the support (35) to the cylinder head, then remove the support (35) by unhooking the spring (36) from the fin disc (37) and the tie rod (38). 24 When mounting, remember to tighten the screws (34) to the specified levels and avoid a drop in pressure with the risk of burning the cylinder head gasket.
<= ...BACK... <= WORKSHOP MANUAL 6.6.0 IGNITION SYSTEM SV 150 2004 to •••• page 1 / 3 from 6.6 IGNITION SYSTEM GENERAL INFORMATION The ignition system has a flywheel with an electronic coil which supplies high voltage to the spark plug. The starting system can malfunction in the following ways: • the engine does not start (if not due to another cause): = no spark on the spark plug due to a faulty coil [ 6.6.A]; = coil to earth [ 6.6.B and 6.7.
<= ...BACK... <= WORKSHOP MANUAL 6.6.0 IGNITION SYSTEM SV 150 2004 to •••• page 2 / 3 from and to earth on the engine (5). Activate the starter and see in the instrument if the spark jumps. 3 If the test has a positive result, clean the electrodes (2) with compressed air and adjust the distance to 0.6-0.8 mm. Remount the spark plug and tighten it to the specified levels. 5 Otherwise, check the system parts as described in point “B”.
<= ...BACK... <= WORKSHOP MANUAL 6.6.0 IGNITION SYSTEM SV 150 2004 to •••• page 3 / 3 from 17 Carry out a spark test as described in point “A”: – If the spark jumps = the coil functions correctly, so if the system malfunctions, it is due to the earth microswitch or relative cable [ 6.7.B]; 17 16 – If the spark does not jump = the coil is faulty and must be replaced [ point “C”]. 18 Remount the conveyor [ 6.1.A]. C) Replacing the coil 21 Remove the conveyor with the tank [ 6.1.A].
<= ...BACK... <= WORKSHOP MANUAL 6.7.0 TURNING OFF AND STOPPING THE ENGINE SV 150 2004 to •••• page 1 / 3 from 6.7 TURNING OFF AND STOPPING THE ENGINE GENERAL INFORMATION The engine is turned off and stopped by releasing a lever on the lawnmower. The cable acts on a lever which simultaneously activates a microswitch that sends the coil to earth as well as a brake which acts on the flywheel. The brake must be able to stop the engine within 3 seconds after it is turned off.
<= ...BACK... <= WORKSHOP MANUAL 6.7.0 TURNING OFF AND STOPPING THE ENGINE SV 150 2004 to •••• page 2 / 3 from B) Checking the ignition off microswitch 11 Remove the upper conveyor [ 6.1.A]. 12 Disconnect the faston (11) from the coil. 13 Using an Ohmmeter tester, make contact with the prods on terminals “1-COM” and “3-NO” of the microswitch (12); the instrument should read: 11 - ∞ = microswitch pressed - 0 = microswitch free 14 Remount the upper conveyor [ 6.1.A].
<= ...BACK... <= WORKSHOP MANUAL 6.7.0 TURNING OFF AND STOPPING THE ENGINE SV 150 2004 to •••• page 3 / 3 from D) Replacing the system for turning off and stopping the engine 31 Remove the upper conveyor [ 6.1.A]. 25 32 Disconnect the brake wire (21) from the lever (22). 22 29 33 Unscrew the stud bolt (23) and the screw (24) fastening the supporting bracket (25). 21 34 Disconnect the two cables (26) and (27) of the microswitch (28).
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.8.0 EXHAUST SYSTEM 2004 to •••• page 1 / 1 from 6.8 EXHAUST SYSTEM 2 GENERAL INFORMATION The exhaust system consists of a muffler installed on the cylinder together with a gasket, a spacer and a heatproof baffle. A malfunctioning exhaust system may lead to a loss in power or excess noise. However, the muffler is a preassembled part which cannot and must not be disassembled or repaired but only replaced.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.9.0 ENGINE BLOCK 2004 to •••• page 1 / 2 from 6.9 ENGINE BLOCK GENERAL INFORMATION This engine is designed to significantly reduce the need for servicing internal part, which would often turn out so expensive that it would not be worth the money. This chapter describes the only operations that can be carried out on the engine and how to replace it.
<= ...BACK... <= WORKSHOP MANUAL SV 150 6.9.0 ENGINE BLOCK 2004 to •••• page 2 / 2 from facilitate access to the lower part and drain all the oil. 12 Remove the oil filling cap (11) and position a suitable container for collecting the oil. Unscrew the drain plug (12) and let all the oil pour out. 11 13 When fitting the drain plug (12), check that the gasket underneath is intact and positioned correctly. C) Removing the engine 21 Empty the tank of fuel [ 6.1.A].
