I have been researching this same engine tonight. I've gotten 1 reply and they say 25:1. I suppose this is because it is air cooled. Plugs are suppose to be NGK B7HS gapped at .024
I don't have the Mariner year model chart, but close as I can tell this engine would be a 1984 - 1985 year model.
internal tank model is 48#
The 1998 model Mariner outboards use a 50:1 ratio.
The 1998 model, 5 hp Mariner outboard requires a 50:1 ratio, three ounces of 2 cycle oil, to one gallon of fuel.
The dry weight of a 1986 model, 70 hp Yamaha outbord is 235 lbs.
A 75 hp Mariner, serial number OC282117 is a 1990 year model.
i have a 25 hp mariner and i use a 50:1 mixture
The model number 695 555646 corresponds to a Mariner outboard motor that was manufactured in the early 1990s. Specifically, it is likely from around 1991, as Mariner's model numbers typically follow a specific coding system that can help identify the year of production. For precise identification, you may also want to check the serial number or consult Mariner's resources.
The dry weight for a 1993 model, 20 hp Mariner outboard is 112 lbs.
The dry weight of a 1985 model, 100 hp Mariner outboard is 312 lbs.
MARINER - ( 5 H.P. (1985)) Serial No: 00147151 Model No: 7005205 .
A 9.9 hp Mariner outboard, serial number OC269812, would be a 1990 year model.