1998 Johnson Evinrude "EC" 9.9 thru 30 HP 2-Cylinder Outboards Service Manual, Page 259Get this manual
Cleaning and Inspection
Replace damaged componentsShift system failure will cause loss of control over direction of engine thrust1Discard all seals, O-rings, and gaskets
2Clean all jet drive components in solvent and dry with compressed airTo avoid personal injury, wear eye protection and regulate air pressure to not more than 25 PSI (172 kPa)3Perform the following inspections:
Jet drive housingAll surfaces must be free of corrosion and sealerAll threaded holes must be free of corrosion and sealer
Drive impellerCheck impeller for nicks and burrsFile edges to remove any nicks and to keep surface sharp