Hi Scotty,

Discovered a small oil leak origination on the turbo in my 2008 Volvo S80 T6 AWD (automatic) with 194K mi (VIN: YV1AH992781062078).  I've ordered new seals for the oil lines where they attach to the turbo body.  Because there are 4 lines (2 inlet and 2 return) in close proximity to one another, I need to be able to identify the relative positions of the two oil lines (inlet and return) in their proximity to the two coolant lines (inlet and return).  Looking up at the body of the turbo from underneath, it appears that the two return lines are located above the two inlet lines.  But when looking at the two sets, it's not possible to tell which one - within each pairing - is the oil and which is the coolant line.  I state this because all lines show a light covering of oil on each.  Ergo, the presence of oil is not a accurate indicator of the point of leakage.

My game plan (at this point in time) is to just have my mechanic change the two sets of seals on the oil lines (inlet and return).  You could help me out tremendously if you were able to coach me on how to identify the oil lines (inlet and return) in this situation... in so doing, if would be able to inform my mechanic as to which lines are which, if need be.  For example, if you indicate to me that when looking up at the turbo body, the four lines going into the turbo body are readily visible.  The two located at on the upper portion of the turbo body are the return lines and the two located below them are the inlet lines.  So, when looking up at the two return lines, the one on top (i.e., at the highest point on the turbo body) is the oil return line.  And, similarly, when looking at the two inlet lines (they both have banjo bolt attachments) the one located above the other is the oil inlet line.

Note:  I worded my example feedback the way I did is because if both oil seals are leaking simultaneously, then all four tubes would have oil covering them.  Why?  Because, in this instance, the leak would always follow the pull of gravity and cause the flow of leaking oil to be in a downward direction.