Strange problem with 6-71

You may have ruptured your intake gasket . What kinda blowby in the crankcase. Pull your oil cap. If your spraying oily mist , it robably has bad gaskets. Also , question. What will propane show? You have positive manifold pressure. It won't draw the propane in. Correct? I'd be more inclined to find a tech with a smoke check tool. Very useful in finding evaporative emission testing. Just my 2cents