What was found
ON CLIMBOUT, AIRCRAFT WOULD NOT PRESSURIZE, CREW REPORTED LOUD AIRFLOW NOISE COMING FROM CABIN. AIRCRAFT RETURNED TO DEPARTURE AND LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE FOUND THE L-1 MAIN CABIN ENTRY DOOR AFT END OF DOOR WITH A GAP, THE L-1 DOOR WAS ADJUSTED AND RIGGED IAW MM CH 52-11-01 OPERATIONAL CHECK NORMAL, DECAY CHECK ACCOMPLISHED IAW. WORKCARD 829, DECAY NORMAL AND PRESSURIZATION CHECK IAW MM CH 5-51-101 WAS NORMAL. A OVERWEIGHT LANDING INSPECTION WAS ACCOMPLISHED IAW MM CH 5-51-271 NO DEFECTS NOTED, AIRCRAFT WAS RETURNED TO SERVICE.