2007-2009 Yamaha F15/F20 Outboard Service Manual, Page 220Get this manual
Power tilt gear pump (power tilt model)
Disassembling the gear pump
1Remove the manual valve 1, manual release pins 2, relief valve seals 3, and balls 4
S6AG7170
Checking the gear pump
1Check the drive gear and driven gearReplace if damaged or excessively worn2Check the gear pump housingReplace if scratched
Checking the valve seal
1Check the valve seals 1, and absorber valve pins 2Replace if damagedS6AG7071