1983 Yamaha 30EN Outboards Service Manual, Page 52Get this manual
POWER HEAD OVERHAUL DESC IPTION The pOWl-'r head is made up of in-line twin cylindprc;, ""hose bore and stroke is 72 mm (2.83 In) and 61 mm (2.4 in)The total pistofl displacement is 496 cc (30.3 c.in)To produce simultaneous sparks in the two cylinders, clpacitor discharge ignition (COl) system is used
POWER HEAD REMOVAL Wiring removal
1Remove the battery wires from starter relay and electric motor
PREPARATION FOR REMOVAL 1All dirt, mud, dust, and foreign material must be cleanea from the engine before the engine is removed and disassembledThis will help keep foreign material out of the engine2Before engine removal and disassembly, be sure that you have the proper tools and cleaning equipmentWith them you can perform clean and efficient jobNOTE: _