The 1979 model, 25 hp Evinrude requires a 50:1 ratio, one pint of 2 cycle oil, to six gallons of fuel.
For the 1990 model, 25 hp Evinrude outboard, use a 50:1 ratio, roughly 1 pint of 2 cycle oil, to six gallons of fuel.
25 to 1 is the mixture for the fuel
Johnson engines from 1964 on are a 50/1 mixture requirement. Before '64 they were 24-25/1 mixture. Quite revolutionary of Johnson/Evinrude at the time, changed the industry, everyone followed suit shortly after.
.G Argo Boat Company http://www.argoboat-ny.com
My motor says 100 to 1 right next to the fuel connection....
For the Evinrude 25 outboard motor, the recommended oil mixture is typically 50:1 for pre-mixed fuel, which means you should use 2.5 ounces of oil for every gallon of fuel. If your model is a newer direct injection engine, it may use a different oil system, so it's essential to consult the owner's manual or check with a dealer for specific requirements. Always use high-quality 2-stroke oil designed for outboard motors to ensure optimal performance.
A 25 hp Evinrude, model number E25RCNB, would be a 1982 year model.
25:1
An Evinrude 25hp outboard, 1985 year model, requires a 50:1 fuel, to 2 cycle oil ratio. This is roughly one pint of 2 cycle oil, to six gallons of fuel.
25
20/1
25:1