Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-42794--1, Page 266Get this manual
Power Trim System Disassembly Trim Rod Removal
ACAUTION
DO NOT ADJUST OR REMOVE REVERSE THRUST VALVETHIS VALVE IS PRESET AT FACTORY FOR PRECISE REVERSE THRUST PRESSURE AND DOES NOT REQUIRE ADJUSTMENT1Secure power trim assembly in soft jawed vice2Open manual release valve three or four turns (counterclockwise) and position trim rod to full up position3Remove cylinder end cap assembly from cylinder using spanner wrench (14 inx 516 inlong pegs)