Mercury Optimax Models 135, 150, Direct Fuel Injection., Page 315Get this manual
POWER TRIM
IMPORTANT: This trim system is pressurizedRemove "Fill" plug only when outboard is tilted to the full "Up" position or the trimtilt rams are fully extendedRetighten "Fill" plug before tilting outboard down or retracting tilttrim ramsRemove "Fill" plug and O-ringSystem is full when oil level is present at fill holeTighten "Fill" plug securely
aFill Plug and O-ring (remove to fill system, tighten securely)Oil Can (fill system with Quicksilver Power Trim and Steering Fluid)Tilt Lock Lever (engage to support engine in "Up" position)