Whilst checking fluids today I noticed of what I presume is oil in my coolant expansion tank.
there's a very thin layer of gunk floating on top of the coolant, and light brownish gunk on the cap and around the neck where the cap screws on. the gunk almost looks like mould. I'm also getting a bit of white smoke and water droplets out the exhaust. I take it this sounds like the dreaded head gasket?

'91 300E, M103

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1993 320TE M104
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past:

1983 230E W123 M102
1994 E300D S124 OM606 (x2)
1967 250SE W108 M129
1972 280se 3.5 W108 M116
1980 280SE W116 M110
1980 350SE W116 M116
1992 300E W124 M103
1994 E280 W124 M104
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"music and women I cannot but give way to, whatever my business" -Pepys

It's possibly a head gasket or it very well could be corrosion. Either way der cylinder kopf most likely must come off. Don't just slam a head gasket on and slap it back together. Take the head to the machine shop and have them inspect it. This happened to mine and my machinist welded it up and did a valve job with new guides. New guides are really important on these engines.

I don't know how many people on this side of the Atlantic caught your profanity, but I lived in Germany for a couple of years so you made me feel at home.

Good luck with it,

Danke...

I figured what with it being a German car 'an all

I'll keep an eye on it see what my tech says when I take it in for it's 197k oil change.

__________________
1993 320TE M104
---------------------------------------------------
past:

1983 230E W123 M102
1994 E300D S124 OM606 (x2)
1967 250SE W108 M129
1972 280se 3.5 W108 M116
1980 280SE W116 M110
1980 350SE W116 M116
1992 300E W124 M103
1994 E280 W124 M104
----------------------------------------------
"music and women I cannot but give way to, whatever my business" -Pepys