1996 Johnson/Evinrude Outboards 25, 35 3-Cylinder Service Manual, Page 272Get this manual
Component Description [] UP CHECK VALVEWhen opened by pump pressure, it directs fluid to bottom of cylinder to move piston UPWhen opened by pump control piston, it allows low pressure fluid to return to the pump as the piston moves DOWN
rn MANUALallows the engine to beWhen opened minimum of RELEASE VALVE three turns, it manually raised or lowered
DOWN CHECK VALVEWhen opened by pump pressure, it directs fluid to top of cylinder to move piston DOWNWhen opened by pump control piston, it allows low pressure fluid to return to the pump as the piston moves UP
PUMP CONTROL PISTONMoved by pump pressure, it controls the UP and DOWN check valves Together, they control fluid direction and cylinder movement[] DOWN RELIEF VALVEOpens at approximately 1600 PSI (11,032 kPa) to protect the unit from extreme operating pressures when the cylinder is completely retracted[EXPANSION RELIEF VALVEProtects the unit from extreme pressures caused by thermal expansion of the fluid