Have a 1993 9.9hp evinrude rope start motor. While going at full speed, motor seems to skip a beat a few times then when slowed do, motor runs rough. Hard starting at times. Pulled plugs. Lower plug was wet. Didn't seem to be firing properly. Pulled wire on lower plug while engine was running. No change in operation. Pulled wire on upper plug with wire back on lower plug, motor shut off. Changed wires and got same result. Replaced coil pack. Seems a little better but had to increase start-idle to get it to start easier. Did compression test and both cyclinders come up over 100. Does this sound like it could be a problem with either the power pack, the head gasket, or the carboratour? Any ***istance would be greatly appreciated. Thank you.