Started misfiring on # 3 Cly. , Noticed oil in the spark plug tube. I installed new upper seals , cover gasket and spark plugs. Car ran on all 4 for a little while and started to misfire again. I again noticed oil in the tube. First thing to come to mind was does it have lower seals ? Depends who you talk to and maybe a crack in the tube. Can somebody please tell me if iit does have lower seals..

Txs,
Paul

 

It does not have lower seals. That stopped a couple years earlier than your car.

Are you sure you installed the upper tube seals right-side-up? And if I remember right, they're a bit tricky to get them to stay in the right place as you lower the valve cover down into position.

And, the smooth surface of the head (where those seals bear against) has to be clean and free from scratches.