87 300D Significant Oil Leak (sometimes)

My daughter's 1987 300D (W124) has developed a significant oil leak during highway driving. No significant oil loss in normal city driving but it goes through a quart of oil in 100 miles at highway
speeds, and leaves a huge puddle of oil when she stops.
She has a pretty good mechanic in her town who took a quick peek and said it "looks like the turbo". She is going take it back for a closer look but I'm somewhat skeptical about needing to replace the turbo.
I searched for posts with similar problems and found replies talking about return line seals and separator problems, but for models (even) older than this one.
Any thoughts on what this might be and/or anything we could point her mechanic to look at?
....................Scott
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Cylinder head gasket.
--
2007 T.G.Lambach. Publication in any form requires prior written
permission.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

oil pan. How may miles are on the engine?

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Over 250K miles on engine.
..............Scott

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
The turbo oil return line seal is in my experience the biggest source of oil leaks on these engines. It's probably original to the car and rubber just don't last that long; it should probably be replaced on principle. At the risk of sounding snotty a mechanic familiar with these cars would now this: they all leak from there at some point.
--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Jul 13, 5:39 am, snipped-for-privacy@news.vrx.net (Richard Sexton) wrote:

Mine (turbo return line) is actually leaking on my 84 300D. Its actually the only thing dripping oil on the entire engine. (262k miles on it) I bought the replacement O-rings, and lower rubber gasket, but how the heck do you get that thing off? The only place it is mentioned in the Haynes manual is when you are removing the turbo. Can I do this repair with the turbo still on the car? If not, how big of a pain is it to remove the turbo? (i.e. Am I gonna make things worse if I take the entire turbo off to fix this leak?)
Its leaking less than a quart for the 2500 miles that I have had it.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It's probably possible with the turbo still on but I sure wouldn't do it and it's not too hard to remove. The trick to gettinf the old one seal out is to put a hose clame around it, compress then pull it out. It's still hard, and hard to get back in though... but doable.
--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Jul 14, 11:26 am, snipped-for-privacy@news.vrx.net (Richard Sexton) wrote:

Thanks for the reply Richard. I am getting things in order to do the repair soon, so hopefully everything will go off (and on) well. Are there any other seals, gaskets, etc. that I would need for this replacement? (As in for the oil supply line, or manifold connection.)
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Patience, hard liquor and/or drugs helps. It's really a pig of a job. You'll need a manifold gaskets.
--
Need Mercedes parts? http://parts.mbz.org
Richard Sexton | Mercedes stuff: http://mbz.org
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.