What was found
INSPECTION TYPE-N/A, WHEN STARTING NR 3 ENGINE SMOKE OF UNKNOWN ORIGIN ENTERED THE FLIGHT DECK. SHUTDOWN ENGINE AND ALL ELECTRICAL AND EVACUATED AIRCRAFT. FIRE DEP WAS CALLED, OPENED MAIN ENTRANCE DOOR. SMOKE WAS DETECTED, CHECKED ALL AC PACKS RAN ENGS. OPERATED BOTH PACKS RECIR FAN, ALL SMOKE TAKEN OUT OF CABIN. FOUND SMOKE COMING FROM EXTERNAL AIR SOURCE, AIRCRAFT SECURE OK.