2007-2009 Yamaha F15/F20 Outboard Service Manual, Page 137Get this manual
Power unit
Installing the cylinder head
1Install new gasket and the cylinder head, and then tighten the bolts to the specified torques in the sequence shownS6AG5430
2Check the inner surface of the oil pump caseReplace the oil pump assembly if scratched3Measure the oil pump rotor clearances as shownReplace the oil pump if out of specificationS6AG5440