Engine - Yamaha 2009 YFM25RY Service Manual

ENGINE REMOVAL ......................................................................................5-1
INSTALLING THE ENGINE ....................................................................5-4
INSTALLING THE MUFFLER AND EXHAUST PIPE..............................5-4
CAMSHAFT ..................................................................................................5-6
REMOVING THE ROCKER ARMS AND CAMSHAFT ...........................5-7
CHECKING THE CAMSHAFT ................................................................5-7
CHECKING THE ROCKER ARMS AND ROCKER ARM SHAFTS ........5-8
INSTALLING THE CAMSHAFT AND ROCKER ARMS ..........................5-9
CYLINDER HEAD.......................................................................................5-10
REMOVING THE CYLINDER HEAD ....................................................5-12
CHECKING THE CYLINDER HEAD ....................................................5-12
CHECKING THE TIMING CHAIN GUIDES ..........................................5-13
CHECKING THE TIMING CHAIN TENSIONER ...................................5-13
INSTALLING THE CYLINDER HEAD ...................................................5-14
VALVES AND VALVE SPRINGS ................................................................5-16
REMOVING THE VALVES ....................................................................5-17
CHECKING THE VALVES AND VALVE GUIDES .................................5-17
CHECKING THE VALVE SEATS ..........................................................5-19
CHECKING THE VALVE SPRINGS......................................................5-21
INSTALLING THE VALVES...................................................................5-22
CYLINDER AND PISTON ...........................................................................5-24
REMOVING THE PISTON ....................................................................5-25
CHECKING THE CYLINDER AND PISTON.........................................5-25
CHECKING THE PISTON RINGS ........................................................5-26
CHECKING THE PISTON PIN .............................................................5-27
INSTALLING THE PISTON AND CYLINDER .......................................5-27
CLUTCH......................................................................................................5-29
REMOVING THE CLUTCH...................................................................5-32
CHECKING THE FRICTION PLATES ..................................................5-32
CHECKING THE CLUTCH PLATES.....................................................5-33
CHECKING THE CLUTCH SPRINGS ..................................................5-33
CHECKING THE CLUTCH HOUSING .................................................5-33
CHECKING THE CLUTCH BOSS ........................................................5-33
CHECKING THE PRESSURE PLATE ..................................................5-34
CHECKING THE CLUTCH PUSH RODS.............................................5-34
CHECKING THE PRIMARY DRIVE GEAR ..........................................5-34
INSTALLING THE CLUTCH..................................................................5-34
OIL PUMP ...................................................................................................5-38
REMOVING THE OIL PUMP ................................................................5-40
CHECKING THE OIL PUMP ................................................................5-40
CHECKING THE BALANCER WEIGHT GEAR....................................5-40

ENGINE

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