2003 Johnson ST 6/8 HP 4 Stroke Outboards Service Manual, PN 5005471, Page 48Get this manual
MAINTENANCE LUBRICATION
LUBRICATION
Engine Oil and Filter Service
IMPORTANT: 4-Stroke outboards are shipped without oil in the crankcaseOil must be added to the crankcase before starting the engine for the first timeIt is recommended to add Evinrudel Johnson Ultra 4-Stroke synthetic blend oilOil Level
With the motor in the vertical position, fill the oil sump until the oil level is between the ilL" and "F" marksStart and run engine for few minutes and recheck oil level after engine has cooled downAdd oil if necessary
approved 10W-40 or 10W-50 oil may be usedChange this oil every 100 operating hoursWhen preparing to change the oil, drain or siphon the old oil after period of engine operationWarm oil flows more quickly and completely and contains more suspended sludge than cold oilIf changing oil only once season, time the work so the motor contains clean oil during storage