Borescope #4

[PeytonM]

IO360A3B6D Cylinder #4 was IRAN ‘d about 100 hrs ago December 2023, on an engine at 1900 SMOH. Since then compressions good and oil usage one qt/6 hrs. Airplane OTS since January 2025 because of medical issue, but dehydrator plugs and EngineSaver since. Annual nearly completed. WHAT AM I LOOKING AT??

[N201MKTurbo]

Some very strange deposits on your exhaust valve and it is not rotating. Can you get a pic with the valve open?