Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-42794--1, Page 384Get this manual
Internal Oil Filter Installation 1Install O-ring (a) on 2-pin receptacle (b)Then install receptacle in tank (c)
3Install nut (a) onto tank receptacle using 23mm wrenchHold receptacle in tank using Quicksilver AutoSlend Service Tool Wrench (91-16748) Torque nut to 20 lbin (2.20 Nm)