1993 Johnson Evinrude "ET" 90 degrees CV Service Manual, P/N 508285, Page 319Get this manual
Component Description This valve controls maximum oil pressure in the system during trim-outltilt-upIt also bleeds oil to the reservoir when the engine is run at speeds over 1500 RPM (approximately) in the partial-tilt positionThis allows the engine to return to the maximum trim-out positionmovement of the engineWhen this screw is loosened, the engine will not move in the trim range
Ial Trim-up Relief Valve
Ial Manual Release ValveThis device allows manual tilting
f4l Tilt Cylinder
This hydraulic cylinder moves the engine through the tilt range onlyIt also absorbs the shock of hitting an underwater object
from the oil pump to the underside of the tilt position while trimming out and tilting up
Is1 Tilt Check ValveThis valve provides one-way oil passage
cylinder as it retracts when coming off shallow water drive modeThe valve also filters the oil
Ial Filter ValveThis valve supplies oil to the top side of the tilt
Check Valve CDThis valve, along with the trimtilt separation valve, isolates the trim cylinders from the rest of the system when the engine is not being trimmed or tiltedIt allows oil to flow from the pump to the underside of the trim cylinders during trim-out operationIt also allows oil flow to return to the pump and reservoir during trim-intilt-down operation