Mercury Optimax Models 135, 150, Direct Fuel Injection., Page 269Get this manual
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3Apply thin, even coat of Loctite Master Gasket #203 on mating surfaces of crankcase cover and cylinder block4Place crankcase cover in position on cylinder blockTurn the center main bolts in LITTLE at time, (following torque sequence) compressing crankshaft seal rings until crankshaft cover has been drawn down to cylinder blockTighten eight bolts (a) evenly in three progressive steps (following torque sequence)5Install remaining crankcase cover flange bolts6Tighten end cap bolts to specified torque