There is a lot of test to do to see why a motor won't fire and its way to many for me to type all of them so start with the kill switch to make sure it not gone bad on you. Disconnect it and see if it will fire.
That fuel running out the lower unit is happining every time it tryies to be started because that fuel has to leave that motor from some where. You are going to need a manuel and if you have a local library then go down and read up on this motor in the trouble shooting section.