A B737-400 EXTERNAL POWER RECEPTACLE CUTOUT DOOR LATCH WAS REPLACED WITH AN INCORRECT LATCH ASSEMBLY; REQUIRING ACFT TO RETURN TO GATE.

Narrative

MR X AND I WERE CALLED ON THE RADIO BY THE LINE SUPVR ABOUT A BROKEN LATCH FOR THE EXTERNAL PWR DOOR ON ACFT Y. IT WOULD BE IN SOON. HE SAID MAINT CTL WOULD LIKE US TO CLR THE DEFERRAL AT THAT TIME TO END RE-INSPECT OF THE SPD TAPE APPLIED IN THE DEFERRAL. WE PULLED THE EXTERNAL PWR DOOR KIT WE HAVE IN THE SHEET METAL VAN FOR MD80 ACFT. AFTER VERIFYING THE CORRECT LATCH IN THE IPC; WE WAITED FOR THE ACFT TO ARRIVE. 15 MINS PRIOR TO ARR; WE WERE TOLD BY MAINT COORDINATOR THAT MAINT CTL WAS UNSURE IF THE ACFT IN QUESTION WAS ACFT Y OR ACFT X ARRIVING. ACFT Y ARRIVED. AFTER VERIFYING THE DISCREPANT EXTERNAL PWR DOOR WAS NOT ACFT Y; WE PUT THE KIT BACK ON THE SHELF AND PULLED THE B737-400 EXTERNAL PWR DOOR KIT. I EMPTIED THE KIT OUT ONTO THE BENCH AND PRINTED THE IPC REF FOR ACFT X (EXTERNAL PWR DOOR). FINDING THE CORRECT PART NUMBER IN THE IPC; I SHOWED MR X HOW THE LATCH HAS ITS PART NUMBER STAMPED ON THE PART. WE HAD AT THAT TIME THE CORRECT LATCH. I DO NOT RECALL THE FULL PART NUMBER AT THIS TIME. BUT I DO KNOW THAT THE LAST 3 NUMBERS WERE -XXX. THE LATCH WAS THEN SET DOWN ON THE BENCH WITH ALL THE TOOLS TO DO THE JOB WHEN ACFT X ARRIVED. THE KIT WAS STILL SPREAD OUT ON THE BENCH. WE THEN RECEIVED A CALL TO ANOTHER ACFT FOR A DENT IN THE #1 SLAT LEADING EDGE R WING. IT WAS HANDLED WITH 15 MINS TO SPARE. PROCEEDING TO THE GATE; WE WAITED FOR THE ACFT. I MOVED THE TOOLS AND A LATCH FROM THE BENCH TO THE FRONT OF THE VAN IN A BUCKET. I DID NOT REALIZE THAT ANOTHER LATCH (A -YY?) WAS ALSO MIXED IN WITH THE -XX LATCHES. WE INSTALLED THE LATCH ON THE EXTERNAL PWR DOOR; MADE SURE THE LATCH OPENED AND LOCKED CORRECTLY BUT DID NOT CHK TO SEE IF IT WOULD LATCH IN THE DOOR CUTOUT SINCE ALL IT WAS MISSING WAS THE BUTTON. THE ACFT PUSHED BACK FROM THE GATE AND THE RAMP WAS UNABLE TO LATCH THE DOOR. THEY CAME BACK TO THE GATE AND WE THEN NOTICED THE WRONG LATCH WAS INSTALLED. WE REMOVED IT AND INSTALLED THE CORRECT ONE; VERIFIED IT LATCHED IN THE DOOR FRAME AND SIGNED MAINT LOG PAGE. THE 2 LATCHES LOOK VERY MUCH ALIKE AND I NEVER DOUBLECHKED THE PART NUMBER AT THE ACFT.