Engine - Yamaha YFM70RY Service Manual

ENGINE REMOVAL ........................................................................................ 5-1
INSTALLING THE EXHAUST PIPES AND MUFFLER ............................. 5-2
INSTALLING THE ENGINE....................................................................... 5-7
CYLINDER HEAD............................................................................................ 5-8
REMOVING THE CYLINDER HEAD......................................................... 5-9
CHECKING THE CYLINDER HEAD ......................................................... 5-9
CHECKING THE CAMSHAFT SPROCKET............................................ 5-10
CHECKING THE TAPPET COVERS AND
CAMSHAFT SPROCKET COVER ......................................................... 5-10
CHECKING THE TIMING CHAIN TENSIONER...................................... 5-10
INSTALLING THE CYLINDER HEAD ..................................................... 5-11
CAMSHAFT ................................................................................................... 5-14
REMOVING THE ROCKER ARMS AND CAMSHAFT............................ 5-15
CHECKING THE CAMSHAFT................................................................. 5-15
CHECKING THE DECOMPRESSION SYSTEM..................................... 5-16
CHECKING THE ROCKER ARMS AND ROCKER ARM SHAFTS ........ 5-16
INSTALLING THE CAMSHAFT AND ROCKER ARMS .......................... 5-16
VALVES AND VALVE SPRINGS.................................................................. 5-19
REMOVING THE VALVES...................................................................... 5-20
CHECKING THE VALVES AND VALVE GUIDES .................................. 5-20
CHECKING THE VALVE SEATS ............................................................ 5-22
CHECKING THE VALVE SPRINGS........................................................ 5-23
INSTALLING THE VALVES .................................................................... 5-24
CYLINDER AND PISTON.............................................................................. 5-26
REMOVING THE PISTON ...................................................................... 5-27
CHECKING THE CYLINDER AND PISTON ........................................... 5-27
CHECKING THE PISTON RINGS........................................................... 5-28
CHECKING THE PISTON PIN ................................................................ 5-29
INSTALLING THE PISTON AND CYLINDER ......................................... 5-29
AC MAGNETO AND STARTER CLUTCH .................................................... 5-31
REMOVING THE AC MAGNETO ROTOR.............................................. 5-33
CHECKING THE STATOR COIL AND
CRANKSHAFT POSITION SENSOR ..................................................... 5-33
CHECKING THE STARTER CLUTCH .................................................... 5-33
CHECKING THE TORQUE LIMITER...................................................... 5-34
INSTALLING THE AC MAGNETO .......................................................... 5-34
ELECTRIC STARTER ................................................................................... 5-36
CHECKING THE STARTER MOTOR ..................................................... 5-38
ASSEMBLING THE STARTER MOTOR................................................. 5-39

ENGINE

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