1990 Johnson Evinrude "ES" 9.9 thru 30 Service Manual, P/N 507871, Page 138Get this manual
Disassembly
INote Check the inner exhaust cover for pitting and flatness If
pitting exists or the cover is warped, discard it and replace with new cover during reassembly
1Remove the three screws retaining the crankcase head to
LJ the powerheadUsing mallet and punch, drive the seals
from the crankcase head Discard the O-ring and seals2Remove the exhaust cover screwsIf necessary, tap the
t=J exhaust cover edge with rawhide malletRemove the inner
and outer exhaust covers; carefully separate the pieces