it's blow by. if you install an oil catch can it would decrease the amount of oil that you find when you take off the piping. if you read a toyota service manual it will tell you that its not uncommon to see a residue. by residue I mean that when you take the accordian hose off, you will might see about a teaspoon or so in-between the ribs depending on how fresh your rebuild is. Does this help?
Whasian
Whasian