Yamaha 90A - Chapter 5 Power Unit

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POWR
CHAPTER 5
POWER UNIT
EXPLODED DIAGRAM ................................................................................... 5-1
PREPARATION FOR OVERHAUL .................................................................. 5-3
REMOVAL ....................................................................................................... 5-3
DISASSEMBLY ............................................................................................... 5-5
INSPECTION ................................................................................................... 5-6
CYLINDER HEAD...................................................................................... 5-6
CLEANING ......................................................................................... 5-6
INSPECTION ...................................................................................... 5-6
CYLINDER BLOCK.................................................................................... 5-7
CLEANING ......................................................................................... 5-7
INSPECTION ...................................................................................... 5-7
PISTON ..................................................................................................... 5-8
CLEANING ......................................................................................... 5-8
INSPECTION ...................................................................................... 5-8
PISTON RING ........................................................................................... 5-9
INSPECTION ...................................................................................... 5-9
PISTON PIN AND SMALL END BEARING............................................ 5-10
CLEANING ....................................................................................... 5-10
INSPECTION .................................................................................... 5-10
CRANKSHAFT ........................................................................................ 5-10
INSPECTION .................................................................................... 5-10
REED VALVE........................................................................................... 5-11
INSPECTION .................................................................................... 5-11
THERMOSTAT........................................................................................ 5-12
CLEANING ....................................................................................... 5-12
INSPECTION .................................................................................... 5-12
CRANK MAIN BEARING........................................................................ 5-12
CLEANING ....................................................................................... 5-12
INSPECTION .................................................................................... 5-12
DRIVE GEAR (OIL INJECTION PUMP DRIVE) ...................................... 5-13
INSPECTION .................................................................................... 5-13
DRIVEN GEAR (OIL INJECTION PUMP DRIVE).................................... 5-13
INSPECTION .................................................................................... 5-13