1983 Yamaha 30EN Outboards Service Manual, Page 92Get this manual
Upper case and mount rubber 1Check the mount rubber for damage and wearReplace parts if damaged Check the friction piece for wearReplace if worn3Check the pivot shaft bushings (top, upper, lower, and bottom) for wear and salt accumulationApply grease or replace part(s) as required2Check the contact surface of the upper casing with the engine for scratches and water leakageReplace if damaged3Check the water tube and water seal rubber sealing surface for water leakageReplace if damaged