What was found
UNABLE TO MAINTAIN PRESS URIZATION. LOUD SQUEALIN G AT DOOR 1L. NOTED L1 DOOR SEAL TORN CENTER BOTTOM EDGE APPROX 2 IN THE A/C DID MAKE AN AIR RETURN AND THE CREW WAS DEBRIEFED. PER THE CAPTAIN JOHN LAMOND THE A/C DID NOT HAVE AN OVERWIEGHT LANDING. REMOVED BULB AND DIAPHRAGM SEAL AS PER AMM 52-09-14-000-801 INSTALLED NEW BULB SEAL UP TO STEP F-3-(G). REF AMM 52-09-14-400-801. REMOVED AND REPLACED BULB AND DIAPHRAM SEAL ON L-1 DOOR REF AMM 52-09-14-400-801. ACCOMPLISHED CABIN LEAK CHECK REF 05-51-91-790-801. LEAK CHECK GOOD.