I have a mid 90's Mercury 9.9hp 2 stroke outboard that won't start. I bought it used and can't get it started. Supposedly it worked the day before I bought it. I have checked everything I can think of. Both plugs get a good spark with brand new plugs. I have verified that the float in the carbeurator is not plugged. I have sprayed starting fluid in the carb as well as directly through the spark plug hole. I am getting compression and gas is flowing. No matter how long I pull the rope, it doesn't even try and fire. Is there something I might be missing?