back in old days that's the 60s by the way. I ran into a couple of fes with this problem and it turned out to be fuel pump seal pumping fuel into the oil pan and diluting the oil so it gets past the rings and burns and goes out the tail pipe I saw a truck with an fe at the sce shop that blew up blew the dist. out and valve covers and oil pan and dip stick out so you might want to invest in a new fuel pump good luck ......ted