Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-42794--1, Page 273Get this manual
3Remove check valve components from manifold ACAUTION
Do not remove check ball components from trim rod pistonRemoval and reinstallation of check valve could result in improper operating pressure and possible power trim system damageo
abcdefghManifold Spring Check Valve Check Valve Seat O-ring Spring Sleeve Spool
aCheck Ball Components
Inspect check valve for debris; clean debris from check valve if foundIf debris cannot be cleaned from check valve, replace trim rod piston as an assemblyClean trim rod and components with parts cleaner and dry with compressed airIt is recommended that all a-rings in trim system be replaced Inspect trim rod If scraper (located in cap) has failed to keep rod clean, replace scraperLubricate all a-rings using Quicksilver Power Trim and Steering Fluid or; (ATF) Type F, FA or Dexron II