1988 Johnson Evinrude "CC" 9.9 thru 30 Service Manual, P/N 507660, Page 59Get this manual
7Inspect propeller shaft seals for evidence of leakageReplace if necessary 8Drain and refill gearcaseLubricate all components of engineSee Lubrication, this section9Check propeller conditionReplace if damaged 10Retorque all screws and nuts to specifications11Run engine in tank with proper test wheelCheck cooling system operation To remove internal carbon, inject GMC Engine Tuner per directions on can DO NOT allow cleaner to soak in engine more than one hourCheck full-throttle test wheel RPMCheck fuel system for leaks!