I picked up a 1982 4HP Evinrude which the previous owner said was running before he put it to rest because of health issues. I changed the oil in the lower leg since he had drained it and there was only very little oil that came out with some black carbon soot or similar thing. I pumped new oil and had some of it oozing from the upper hole and some more black stuff oozed out but not as much as before. I mixed outboard oil Tw3C to a ratio of 50:1 in 10liters of fuel. I filled it into the tank on the top of the motor and opened the air vent. I flicked the switch to fuel, opened choke and put the motor in neutral, brought the knob to start position from stop. Then I cranked the cable but nothing happened. I cranked it quite a few times and it was dead. Please guide me on how I should go about each step to understand this motor. I don't want to take it to a tech unless I have tried it and failed. Please help.