1998 Johnson Evinrude EC 50 thru 70 HP 3-Cylinder Service Manual, Page 91Get this manual
Carburetor Body
1Check all drillings and passages with syringe filled with isopropyl alcohol2Visually inspect all gasket surfaces for nicks or irregularities3Check for excessive throttle shaft playCheck for throttle valve misalignment[] 4Remove the vent well core plug to inspect the pocket for damage or restrictionsDrive small punch not more than 'e in(3 mm) through plug and pry out
5Check for leaks between emulsion pickup tube and carburetor body: Invert carburetor body and fill idle circuit with isopropyl alcohol Check for leaks at point If leak occurs, blow dry and apply drop of OMC Ultra Lock at point