1993 Johnson Evinrude "ET" 9.9 thru 30 Service Manual, P/N 508282, Page 173Get this manual
11916Remove all the screws from the cylinder head water cover,
tap is around the edge with soft mallet to break the seal, and then remove itRemove the thermostatsealand spring Then, remove the cylinder headand the bottom piston dome "No2"
12017With number punches, mark the top piston dome "No1"
8Remove the inner and outer exhaust covers; carefully separate the pieces and clean the gasket surfaces
Check the inner exhaust cover for pitting and flatnessIf pitting exists or the cover is warped, discard it and replace with new cover during reassemblyRemove the intake bypass cover and clean the gasket surfaces