Cylinder Head Damage

Hi All

I have recently been using about half a pint of water every 500 miles on my 03 Mk4 Golf TDI 130. The coolant is also overpressurising and has tested positive for combustion gasses. As a result I am in the process of changing the head gasket.

I now have the head removed and there are very slight ridges on the head along the circular outline of the cylinder bore. The ridges seem to be metal rather than carbon. It is not all the way roun the outline but is present in parts on all cylinders.

Apart from that the cylinder and block look in good condition considering the 210k miles it has done.

Has anyone seen these ridges before?

Thanks

Pulling the cam, lifters and valves is trivial on these engines and having it
skimmed sounds like a good idea for a leaker.
If I had the head off (and I have), I would get it tanked and LAP the seats, too.

Don't remember about the ridges.

Can you post pictures?

You wouldn't see them they are so slight. Especially now I have cleaned it up.

I'm starting to think it was carbon as a friend has just said he has taken of carbon buildups that looked metallic in the past.

Just been out to try and get some pictures but it's no use in this light. Maybe tomorrow when it's light again. The ridges are very small. You can feel them with your finger nail but not the skin of your finger tip.