1999 "EE" Outboards Accessories Service Manual, P/N 787026, Page 86Get this manual
Tilt-DOWNTrim-IN Mode 1When the DOWN button is pressed, the tri mtilt motor rotates counterclockwise (as viewed from the pump end) and turns the pump gears2Fluid pressure passes through the DOWN shuttle valve tothe UP shuttle valvewhich mechanically opens the UP check valve 3Fluid pressure pushes the DOWN check valve off its seat and fluid passes through the valve to the top of the tilt cylinder, to move the tilt piston DOWN4When the swivel bracket contacts the top of the trim rods, the mechanical force of the tilt cylinder pulling the engine down also pushes the trim pistons downFluid is pulled from the reservoir to the top of the trim cylinders5Fluid from the bottom of the cylinders returns through the open UP check valve to the pump6In the tilt range, all of the fluid from the bottom of the tilt cylinder returns through the UP check valve to the pumpSince more fluid is returning to the pump than is required to fill the top of the cylinder, the excess fluid is vented through the DOWN relief orifice to the reservoir7In the trim range, fluid from the bottom of all the cylinders is routed to the pump, which feeds only the top of the tilt cylinderAll of the excess fluid vents through the DOWN relief orifice to the reservoir8When all cylinders are completely retracted, all of the pump output vents through the DOWN relief orifice to the reservoir at stall pressure (approximately 800 PSI)