Thanks for the help

Is the despression "feelable" by touching with the fingertip?
Sure thats a crack? Looks like dirt or a piece of the gasket.


Gude Mario Audi 100 CD Autom. Bj.83 Audi 200 20v Bj.89 Audi 5000 Bj.85 Audi V8 3,6 Autom. Bj.88