What was found
THE COCKPIT AND CABIN FILLED WITH SMOKE AFTER TAKEOFF FROM EWR. THE AIR CONDITIONING SMOKE CHECKLIST WAS ACCOMPLISHED AND A RETURN TO EWR WAS BEGUN. THE CREW NOTED A HYDRAULIC SYSTEM LOSS ON FINAL APPROACH. THE A/C LANDED WITHOUT INCIDENT. MX FOUND THE NR 1 ENGINE HYDRAULIC PUMP PRESSURE LINE LEAKING AND THE NR 1 ENGINE 8TH STAGE DUCT WAS LEAKING. BOTH THE HYDRAULIC LINE AND 8TH STAGE DUCT WERE REMOVED AND REPLACED. LEAK AND OP CHECKS WERE GOOD. A BURNOUT CHECK OF PACK AND BLEED SYSTEM FOR NR 1 ENGINE WAS PERFORMED AND ALL CHECKS WERE GOOD. BOTH WATER SEPARATOR BAGS WERE REMOVED AND REPLACED IAW MM 21-51-31.