1993 Johnson Evinrude "ET" 40 thru 55 Service Manual, P/N 508283, Page 39Get this manual
7Inspect propeller shaft seals for evidence of leakageReplace if necessary8Drain and refill gearcaseLubricate all components of engineSee Lubrication, this Section9Check propeller conditionReplace if damaged 10Retorque all screws and nuts to specifications11Run engine in test tank with correct test propellerCheck cool ing system operation12To remove carbon deposits from combustion chambers and pistons, inject OMC Engine Tunerfolowing directions on canDO NOT allow tuner to soak in engine more than one hourDuring engine operation, carbon can build up on internal powerhead components, eventually causing piston rings tostick Adding OMC Carbon Guard '" fuel additive to every tank of fuel is your best protection against such buildup and the resulting mechanical problemsIf OMC Carbon Guard is not used consistently in the fuelOMC Engine Tuner should be applied every 50 operating hours13Check engine operation by verifying minimum test propeller RPMRefer to Engine Specifications, this Section& 14Momentarily pressurize fuel system and check for leaks