The fuel / oil ratio for a 1986 model, 25 hp Mariner is 50:1, roughly one pint of 2 cycle oil, to six gallons of fuel.
The listed dry weight for a 1986 model, 90 hp Johnson outboard is 288-305 lbs, depending on the particular model.
The dry weight for a 1986 Evinrude 9.9hp outboard is 75 to 88lbs. depending on the model.
The dry weight of a 1986 model, 28 hp Johnson outboard is 118 lbs.
The dry weight of an 1986 model, 70hp Johnson outboard, with tilt and trim, is 256 lbs.
The listed dry weight of a 1986 model, 90 hp Yamaha outboard is 270 lbs.
190lbs. No Trim/tilt. Dry.
The dry weight of a 1986 model, 60 hp Evinrude outboard is 230 lbs for the TLCD model, 248 lbs for the ELCD model.
40 weight
If your engine is a 4 cylinder model, it is a 1985. If it is a 3 cylinder model, it is a 1986.
All that can be determined by the serial number only, is that this engine is a pre 1986 year model.
Danny Tartabull