1993 Johnson Evinrude "ET" 90 degrees CV Service Manual, P/N 508285, Page 82Get this manual
Inspection 1Inspect the leaf plate assemblies for damage The gasket surface must be flat, 0.003 in(0,08 mm) The leaf plates must not be distorted The leaf tips must not be cracked or chipped The leaf plate stops must not be distorted or loose Test leaf plate screw tightnessIf loose, retighten using OMC Screw Lock2Inspect the intake manifold All gasket surfaces must be smooth and free of nicks Use machinist's straightedge to check the flatness in all directionsThe mounting surface must be flat, 0.004 in(0,10 mm)All intake manifold components must be perfectly clean before assemblyDo not use strong carburetor cleaner or hot soaking tankAssembly f31 1Place leaf valves on leaf plateIf new valves do not seat on the leaf plate, turn the leaf valves over
Used leaf valves must not be turned over for reuseLeaf valve may break when returned to service, causing serious powerhead damage