all the TU lumps i have seen with excessive mayo in the coolant has been down to sunk liners,
the usual failure i see is just oil leaking from the front corner cam belt end of the head joint,
if there is oil from the bottom of the head but not up the front of it, then this is definitely gasket failure,
as there is a small triangle section bonded into the gasket just at that corner which is the bit that seals the main oil way between the head and block,
this section becomes unbonded then allows oil to flow down the front of the engine,
regards malcolm
Difficulty of headgasket change on Peugeot 206 1.1?
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