1979 4hp Johnson Sea-Horse start issues

[jhightower31]

I just picked up a 1979 4hp Johnson Sea-Horse. The guy I purchased it from showed me that it wants to start when using a starting fluid but it will not maintain idle and keep running. He said that he pulled the carb off and thoroughly cleaned it when it started acting up and replaced the spark plugs in it. I figured for $75 it wasn't a bad deal. Does anyone know what the problem may be?

Also what is the mix ratio on this? Any information about this motor would be appreciated.

Model #- 4R79D