I have what i think its a 78. Evinrude 50hp. recently i was on a long cruise and the motor just started to lose power and stalled out. it was smoking out of the cowling. I tryed to turn the engine over, but it just clicked. the next day i tryed to start it again. when the key is turned on it has a real loud continuos buzzing. now the engine will turn over but not start. whats with the Buzzing???