What was found
AIRCRAFT WAS RUN UP PRIOR TO 50 HOUR INSPECTION AND NO DEFECTS WERE FOUND DURING RUN UP. AFTER INSPECTION, PERFORMED POST INSPECTION RUN AND NOTICED A LOUD SQUEALING NOISE AND SMOKE COMING FROM ENGINE COMPARTMENT. ENGINE WAS SHUTDOWN AND INSPECTION REVEALED THAT ALTERNATOR BELT WAS SLIPPING AROUND PULLEYS. ALTERNATOR WAS FOUND TO BE SEIZED UP. INSPECTED ALTERNATOR WITH BORESCOPE INSIDE OF BLAST TUBE BUT DID NOT FIND REASON FOR SEIZURE. ALTERNATOR WAS SENT BACK FOR WARRANTY CONSIDERATION. CAUSE OF SEIZURE AT THIS TIME IS UNKNOWN.