What was found
(CAN) BROKEN BOLTS ON A FLANGE-QUANTITY 8 BOLTS SHEARED & QUANTITY 5 BOLTS LOOSE BETWEEN 4 O`CLOCK & 8 O`CLOCK POSITION. THIS ACFT HAD JUST RETURNED FROM A TRAINING FLIGHT. ALL ENGINE PARAMETERS WERE REPORTED NORMAL & NO IN-FLIGHT VIBRATIONS WERE REPORTED. VISUAL INSPECTION ON ENGINE FOUND ALL GOOD. AS RECOMMENDED BY FSR, REPLACED ALL BROKEN & LOOSE BOLTS, PN MS9518-13, WITH SERVICEABLE BOLTS & TORQUE TO 36-40" POUNDS. RECOMMENDED TO SEND THE FRACTURED BOLTS TO LAB, TO INVESTIGATE THE CAUSE OF THE FRACTURE.