Cant get this to start, 1971 Evinrude 25hp

I'm having trouble getting this old Rude to fire up, it had been sitting for 15yrs before I got it. It does have electric start but the starter wont really spin the motor too well, maybe 1 revolution per second. It pulls easy enough with the rope starter, If I pull the plugs it will spin fine so I don't think there is any major internal issues. I've got good spark on both plugs, fuel is getting to the cylinders but All I'm getting is an occasional combustion.
The motor seems to have good compression although I haven't put a tester on it yet.
I'm just wondering what I am missing, or what my next move should be.

You should pull the carb off,it is probably gumed up.It will need a new water pump impeller also.Wouldn't hurt to put a little oil down the cylinders.Try a little gas ,oil mix in the carb.No starting fluid.That motor has points,but if you have good spark that may be ok just maybe check down the road.
Those are good motors.I have a 1976.