1991 Johnson/Evinrude EI 60 thru 70 outboards Service Manual, Page 314Get this manual
Trim "OUT" ITiitUP" ode
When operating the hydraulic unit in the trim "out" tilt "up" mode, hydraulic fluid is routed in the following manner:
1Hydraulic pressure is directed to the trim check valve the piston to open the reverse lock check valve
of the pump control piston
, causing
2The trim check valve then opens against very light spring tension and the fluid flows to the base of the trim cylinders
3Additianaf hydraulic fluid opens the tilt check valve and flows to the base of the tilt cylinder4 Fluid returning from the top of the tilt and trim cylinders is directed through the open reverse lock check valve and back to the pumpIt is important to note that all fluid on the return path returns to the pumpBecause the trim and tilt rods displace fluid at the top of the cylinders, the fluid returning to the pump through the reverse lock check is not sufficient to supply the pump, so additional fluid is drawn from the reservoir 5When both the trim and tilt rods are fully extended and the pressure exceeds 1500 psi (10500 kPa), the trim-up relief valve will open, directing the fluid to the reservoir6When the hydraulic unit is trimming outtilting up or when the engine is running in forward gear, the following valves must hold pressure: Trim-up relief valve Tilt trim separation valve Tilt check valve Trim check valve Expansion relief valve Tilt cylinder piston and O-ring Trim cylinder O-rings