1988 Johnson Evinrude "CC" 9.9 thru 30 Service Manual, P/N 507660, Page 110Get this manual
Disassembly
Do not disassemble leaf plate assemblies unless leaf plate seats, leaf valves, or leaf stops are damaged or corroded
f61 1Remove two screws per leaf valve and remove the leaf valves as required2When disassembling leaf plate assemblies, do not lift or bend leaf valvesRemove the leaf stop screws and remove the stops shims, and leaf valves3When disassembled, keep the stops, shims, and leaf valves separated by assemblyAssembly INotel All intake manifold components must be perfectly clean before assemblyDo not use strong carburetor cleaner or hot soaking tankf"7l 1Place leaf valves on leaf plateIf new valves do not seat on the leaf plate, turn the leaf valves over12321
Used leaf valves must not be turned over for reuseLeaf valve may break when returned to service, causing serious powerhead damage2If any leaf valves are standing open, apply light pressure using pencil eraserIf leaf valve closes with light pressure, valve is acceptableIf not, inspect leaf plate for high spots or burrsDo not lap leaf plate on lapping blockIf plate is too smooth, the leaf valves may stick closed after off-season storage3Apply OMC Locquic Primer to mounting screws and allow to air dry12322