How Much Oil Does A Mercury Outboard Take?
How Much Oil Does A Mercury Outboard Take? Remove the filler cap from the back of the powerhead, then fill the outboard with 3 quarts of Mercury 4-stroke marine engine oil and replace the filler cap. How much oil does a 90 HP Mercury 4-stroke take? Model US Crankcase Capacity 90 FourStroke Carbureted5.28 QT. (169