16V TDI: Location of Cylinder Head Crack

Hello, fellow diesel experts,
After it was clearly determined that water was present in the first cylinder of a VW BKD engine (16V TDI), the cylinder head was removed to investigate the cause.
The problem, however, is that this cannot be detected (at all!).
- Is it the head or is it the poetry?

'Neither on the one component nor the other is there any visible evidence of a part that would have channeled water into the cylinder due to deformation. The intake manifold was removed from the cylinder head to examine the intake channels. It was observed that all 8 inlets are identical and covered with a thin layer of black residue. In contrast, it is clearly visible on the piston No. 1 and the valves of cylinder 1 that they are significantly cleaner compared to cylinders 2-4.'

The question now is: how did the water get into the cylinder? There's a known issue with the AZV and BKD engines where the cylinder head can develop a hairline crack, allowing water to enter the combustion chamber. Are there any pictures of this hairline crack, so we can get an idea of the extent of the damage? In any case, there's nothing visible to the naked eye!
The machine has 150,000 kilometers on it.

Thank you everyone.
Sure, here is the translation of the text from German to English:

'Micha'

/viewtopic.php?t=24511&highlight=crack+bkd

Thank you for the information.
'Am I understanding correctly that the crack in the ZK (cylinder head) is irreparable and requires a replacement of the ZK? I had previously assumed that the crack forms on the surface of the sealing area, allowing water to enter the combustion chamber...?'

However, the crack is located in the material between the water jacket and the inlet or outlet channel, and it cannot be patched because it is inaccessible.

Check out my latest post here:

/viewtopic.php?t=24862

SG.

So, I just went to my local specialist for ZK (Zentrale Klimaanlage - central air conditioning) systems.
He's aware of the problem too, and he told me that the crack, as I suspected, is located inside the cylinder head, between the water passage and the intake port, which allows water to enter the intake port.
Therefore, a repair is not possible, and pictures of the crack are also unavailable.
There are always only pictures of the completely clogged intake manifold, but never of the crack itself, which is hidden.

Consider this a final post and the conclusion of this topic.
Thank you to all the helpers!