What was found
INSPECTION TYPE-N/A, AIR TURNBACK DUE TO SMOKE IN COCKPIT AND MAIN CARGO FIRE WARNING. LEFT ENGINE LOST 8 QTS IN 16 MIN OF FLIGHT AND 45 MIN OF BLOCK TIME. CLIMBING THROUGH 12,000 FT MAIN CARGO FIRE WARNING CAME ON AND SMOKE ENTERED COCKPIT. ACCOMPLISHED CHECKLIST. REPLACED LT ENGINE PER TASK CARD 5001. RAN ENGINE PER TASK CARD 500 2, ENGINE RAN IN PARAMETERS.