What was found
ON CLIMB OUT AT 12-15, NOTED FLOW LIGHT & CLIMBING CABIN. UNABLE TO MAINTAIN CABIN PRESS. BOTH PRESS CONT INOPERATIVE, UNPRESSURIZED FLT. REF LP 515938 RT PACK ON MEL 21-08 SIT 2, CONTROL 10838, RT PACK MEL CLEARED ON LP 515943. FLEX COUPLING OFF BETWEEN LT ACM COMPRESSOR & PRIMARY HEAT EXCHANGER. INSPECTED ACM FOR DAMAGE, NONE NOTED. INSTALLED FLEX COUPLING & NEW CLAMP. OPERATIONS TESTED OF LT PACK SYS GOOD IAW AMM 21-51-01. PRESSURIZED ACFT IAW TASK CARD FO443601. OPERATIONS CHECKED GOOD. PERFORMED BIT TEST OF PRESS CONTROLLERS IAW AMM 21-32-03. FAULT SHOWS ACFT MOTOR. R & R OUTFLOW VLV ACTUATOR. OPERATIONS CHECK & BIT CHECKED GOOD IAW AMM 21-32-05.