I just purchased an 82 300d turbo. I changed the oil and drove it 60 miles. Checked the level at my destination topped it up (less than 1/2 a quart) drove home. 3 miles from home the oil pressure plummeted STOP! Oil all over. dipstick not entirely seated in its tube. Added four quarts to get level back on the dipstick. What the bleep! Today I hooked a hose up to the dipstick tube and put the other end in a plastic container. Sure enough filled up half a quart of oil in about 20 minutes. Tried the same tube and container on the valve cover vent, some oily dampness but no appreciable oil in half an hour. Ok so I have some blow by, but is that what is causing the oil to come up the dipstick tube? Should I drive to the junk yard now?