General information on inspecting cylinder walls - AH01.00-N-0300-01A
ENGINE 111, 601, 611.981/987, 612.981, 647.981, 668
When illuminating cylinders, a differentiation must be made on the cylinder barrel between "visual streaks" and "seizure streaks": Visual streaks are usually no more than 3 mm wide and not roughened (e.g. they may be caused by ring contact), and they are not a cause for concern. Honing traces are still visible, i.e. engine OK. If there are seizure streaks (cylinder wear), the cylinder surface is rough, and the honing marks are no longer visible, i.e. the engine has to be repaired.