Mercury Mariner 25HP 4-Stroke Outboard Service Manual 1997, Page 235Get this manual
Shock Rod Installation 1Place trim cylinder in soft jawed vice
Manual Release Valve Installation
1Install "E" clip (if removed) and lubricate O-Rings with power trim fluid 2Insert manual release valve into manifold and tighten securely
2Install lubricated a-ring to memory piston and
place into cylinderPush memory piston all the way to bottom
aMemory PistonG-ring
3Fill cylinder three inches (76.2mm) from top of cylinder using Quicksilver Power Trim and Steering FluidIf not available, use automotive (ATF) automatic transmission fluid4Install shock rod into cylinder until power trim fluid flows through oil blow off ball passageFill remaining cylinder to just below the cylinder threads
Bleeding Power Trim Unit
1Secure power trim unit in soft jawed vise2Remove reservoir plugAdd power trim fluid until its even with the bottom of the fill holeReinstall plug3Close the manual release valve(Turn full clockwise)aReservoir Plug