1993 Johnson Evinrude "ET" 90 degrees CV Service Manual, P/N 508285, Page 20Get this manual
FuelOil Ratios Lubricant Only the following lubricants should be used:
Evinrude Outboard Lubricant Evinrude XP Outboard Lubricant Johnson Outboard Lubricant Johnson GT Outboard Lubricant OMC 2-Cyce Motor Oil
They are formulated to give best engine performance with least combustion chamber deposits, least piston varnish, maximum spark plug life, maximum corrosion protection, and best lubricationIf Evinrude or Johnson Outboard Lubricant or OMC 2-Cyce Motor Oil is not available, another NMMA certified TC-W oil may be usedLook for the certification information on the container label
Running or storing an engine on leaner than recommended fuelloil mixture may result in powerhead damageAvoid the use of the following as they could damage your engine andlor shorten spark plug life: Automotive oils Premix fuel of unknown oil quantity Premix fuel richer than the recommended ratio Oil and gasoline leaner than the recommended ratio