1990 Johnson Evinrude "ES" 60 thru 70 Service Manual, P/N 507873, Page 52Get this manual
Idle Speed Adjustment 1The boat and engine must be in the water under normal operating conditions with the correct propeller installedThe boat's movement must be unrestrainedThe boat must not be tied to dock or trailer2Start the engine and allow it to reach normal operating temperature3 Check idle RPM in FORWARD gear with an accurate tachometer4Stop the engine to prevent contact with rotating partsAdjust the idle speed screw to obtain recommended RPM Turn screw counterclockwise to lower idle speed Turn screw clockwise to raise idle speed I18l ""