What was found
DURING A SCHEDULED INSPECTION, A CYLINDER WAS IN THE PROCESS OF BEING CHANGED DUE TO LOW COMPRESSION. UPON REMOVAL OF THE ROCKER COVER, ALL 4 VALVE SPRINGS WERE FOUND BROKEN. AFTER REMOVAL OF ALL ROCKER COVERS, ONLY ONE VALVE SPRING WAS INTACT. THERE WERE NO DISCREPANCIES NOTED BY THE PILOT AS TO AN ABNORMAL RUNNING ENGINE.