Mar 17, 2012 · Messages 12,673 Location Lexington, KY Water Crafts SeaDoo's: 96 GTI 720, 95 XP 800 Limited, 96 GSX 787. 2000, 18' Bayliner 3.0L. Dec 28, 2013 · 123. 2 stroke outboard oil mix ratio mercury 15hp. 124. 20 litres of petrol how much oil for a mercury 15hp. 125. 2000 15hp mercury outboard 2 stroke. The two stroke Diesel engine does not mix fuel or oil with the combustion air. The crankshaft bearings are lubricated from pressurised oil in the same way as a four stroke engine. The two stroke cycle is so called because it takes two strokes of the piston to complete the processes needed to convert the energy in the fuel into work. Mar 30, 2020 · Outboard boat motors with two cycles manufactured by Johnson and Evinrude after 1964 require a 2 percent fuel to oil mixture. Use 1 cup of outboard motor oil for every 3 gallons of gasoline. The oil needs to be manually added to the gas tank unless the engine has an automatic oiling system. If the motor was manufactured before 1964, a whole pint of oil should be added to three gallons of gasoline.