What was found
OWNER/OPERATOR REPORTED OIL LEAKING FROM REAR OF ENGINE. AFTER THOROUGH CLEANING OF SUSPECTED OIL LEAK AREA, AC ENGINE WAS RUN-UP AND OIL WAS FOUND TO BE LEAKING FROM LT MAGNETO MOUNTING PAD AREA AND DRIPPING OFF OF AFT MAGNETO MOUNTING BOLTS. UPON REMOVAL OF THE LT MAGNETO, A CRACK WAS DISCOVERED IN THE LT MAGNETO MOUNTING PAD. CRACK MEASURED 3.25 INCHES AND RAN DIAGONALLY FROM INSIDE EDGE OF FORWARD MAGNETO MOUNTING BOLT HOLE THROUGH IB AFT MAGNETO MOUNTING BOLT HOLE. SUSPECT CRACK IS AGE RELATED OR DUE TO WARPED MOUNT PAD. LT MAGNETO HAD NOT BEEN REMOVED FROM ENGINE SINCE ENGINE OH AND MAGNETO MOUNTING BOLTS APPEARED TO BE PROPERLY TORQUED.(K)