1993 Johnson Evinrude "ET" 60 degrees LV Service Manual, P/N 508286, Page 83Get this manual
Recirculation System Servicing 1Start the engine and operate at idle speedf1l 2Remove No.1 cylinder recirculation hose from fitting on the cylinder blockSubmerge end of hose in cup of water If bubbles appear, proceed to Step If no bubbles appear, proceed to Step 4operation of all recirculation hoses before proceed3Stop the engineCheck the cylinder block fitting with syringe filled with isopropyl alcohol If alcohol flows freely through fitting, No1 cylinder recirculation system is OK If flow is restricted, clean the cylinder block fitting4Stop the engineRemove the recirculation hose and inspect its condition If hose is damaged, replace hose If hose is OK, proceed to Step 5Remove the carburetors and intake manifoldRemove the No.1 cylinder's two check valvesCheck the fitting with syringe filled with isopropyl alcohol If alcohol flows freely through fitting, replace the two check valves If flow is restricted, clean fitting and screen6Be sure recirculation system passages are clean before installing the intake manifold