The S&S engine has a real problem with the so-called dry sump at the bottom of the engine filling with oil (mine gets about 1.5 quarts on sitting). The pressure relives up through the air intakes. No doubt the oil went up the hose into the intakes.
I have to drain the sump before use. There is an allen plug at the bottom to drain the sump. A real PITA, but heck, it is a Morgan