I have a 1996 15hp evinrude that was not running when I got it. Good spark and compression so I pulled the carburetor off and cleaned it with new kit. There was no information on the setting of the air screw on the left side so I turned it to seat lightly and opened it about 3 turns. I got it to run briefly and ran ok or so it seemed. But then it's almost impossible to restart. Also looking for info at Marine Engine for a serviice manual I saw that it list 1996 15hp motors as 4 cycle. Could that have been my biggest problem since I did not know this and hooked my 2cycle tank to it.