Starter dragging on 2001 Johnson 90 horse outboard

Service the carburetor. Check cooling system. it may clogged. Run it in a tub and monitor heat buildup. When it stops running, do you have ignition spark? If no then the ignition coil maybe shorted when hot or it may have moved due to untightened screws.

I think it is a 1990. See this model chart.

contact the manufacturer for that specification
logically it will depend on the mass inside the vessel

Model # shows it's a 1973 year, 50 horse power. 2 stroke engine with 50 to 1 fuel mix.

Bad coil

Here are a few resources: http://www.themanualstore.com/Evinrude-Johnson-Outboard-Motor-Model-Year-Lookup-Guide-s/232.htm

and the manual too:
http://www.themanualstore.com/Evinrude-Manual-Outboard-Motor-Service-and-Repair-Manuals-s/190.htm

Hi, mix the gas and oil at 50 to 1 and use two cycle outboard oil. Regards Phil.

does it turn or can you hear a click as you try ? if its not turning check the starter brushes and if it clicks then replace solinoide !