What was found
AIR RETURN, LOSS OF "A" HYDRAULIC FLUID. ENG 1 HYD PUMP OFF PRESSURE WOULD INTERMITTENTLY RETURN ON AND OFF WITH GROWL NOISES. REPLACED NR 1 ENG "A" PUMP PER AMM 29-11-11-400-802-0022. REPLACED RETURN FILTER PER AMM 29-15-61 AND EDP FILTER PER 29-15-91. RAN ENG NR 1, NO LEAKS NOTED. ROTABLE PARTS CHANGE INDICATED: PUMP, HYD ENGINE DRIVEN, PART NUMBER OFF 849589, SERIAL NUMBER OFF MX675875.