Jimmie Warren

so i have a 1982 jeep cj5 with a 5.7l 350. it over heated on me the other day, but there is no water in my oil and no white smoke from my tailpipe. the problem was my electric fan went out, so i pulled over and went to the nearest auto parts store and got a new one and hooked it up, all good. however after driving for 5 minutes or more i get white smoke from my valve cover vents. and i hear a popping noise like oil burning. it also looks like i have an oil leak between my block and headders. should there be oil there? bad rings? im concerned about the smoke from my vent. why is it doing that? is it safe to drive?