What was found
WHILE COMPLYING WITH LYCOMING SB518A INSPECTION OF THE THERMOSTATIC BYPASS VALVE, THE NUT WAS FOUND LOOSE. A NEW VALVE, PN 53E19600, SN 61088, WAS OBTAINED AS A REPLACEMENT. WHEN THE NEW VALVE WAS INSPECTED, NUT WAS ALSO FOUND LOOSE. THIS VALVE, ACCORDING TO THE SB, DOES NOT APPLY TO THE INITIAL INSPECTION REQUIREMENTS. ANOTHER VALVE WAS ORDERED AND IT CHECKED OKAY. RECOMMEND A SMALL SPOT WELD INSTEAD OF A CRIMP ON THE NUT TO SECURE THE NUT TO THE SHAFT.