Yamaha 25BMH 30HMH Factory Service Manual, Page 232Get this manual
CYLINDER HEAD
INSTALLING THE CYLINDER HEAD AND CYLINDER HEAD COVER
Install: Cylinder head and cylinder head cover NOTE: Temporarily assemble; cylinder head covercylinder head cover gasketcylinder headand cylinder head gasket in that order, and then install the assembled parts onto the crankcase Apply LOCTITE No.572 on the bolts Tighten the cylinder head mounting bolts and nut in sequence and in two steps of torque