What was found
DURING ROUTINE 50-HOUR EXHAUST SYSTEM INSPECTION, NOTED BOLT AT RIGHT SIDE FORWARD LOWER CRANKCASE JUST ABOVE OIL PAN STICKING OUT AND TOUCHING EXHAUST CROSS-OVER TUBE. REMOVED TUBE, FOUND HEAD OF BOLT POPPED OFF. BOLT HEAD OR WASHER PN 401507 COULD NOT BE LOCATED IN COWLING. INSTALLED NEW BOLT AND WASHER, TORQUED 165 INCH/POUND PER ENGINE OHM. THIS ENGINE IS AN AVIALL OVERHAULED ENGINE FOR TCM COMPLETED 5/89. BOLT SIZE: .3750 INCH - 16 INCHES BY 5.25 INCHES LONG.