1999 "EE" 90, 115 FFI, 150, 175 V4, V6 FFI Outboards Service Manual, P/N 787024, Page 228Get this manual
Install in vacuum testerPump out to 3-5 inches (76-127 mm) Hg and see if vacuum holdsThen, pump out to 15 inches (381 mm) Hg and checkIf the gearcase fails to hold on either test, put oil around suspected sealIf leak then stops or oil is drawn in, that seal is defectiveWhen the gearcase checks OK, refill with the proper lubricant [ill
36Fill the gearcase with lubricant as follows: Secure the gearcase in an upright position Remove the oil level plug and the drainfill plugReplace their seals, if damaged Fill the gearcase with CIVIC Ultra-HPF gearcase lube until it appears at the oil level holeInstall the oil level plug, then the drainfill plugTighten them to torque of 84-86 inIbs(9-10 Nm) Check the oil level after the motor has been run