i have a 1996 12 in a superduty
i just rebuilt engine around 15000 ago and had head reworked i assembled the head but i didnt get seals completly seated the came off gide and slid to top of valve after a week or so i took springs off replaced all ex springs and reinstalled seals the same ones but corectly this time

it has steadly gotton worse asa far as blue smoke and burning oil smell goes going down rd no smoke at all but after a min or so of idling it will really fog up after take off
i guess my question is could seals cause my problem or do i need to look in other areas
new rings were also installed at time of build there is no blow by hardly
very little if any but i do have valve cover leaks any help im tired of of smoke!