What was found
SHIP 5807 FROM THE FLOOR AND CEILING TOWARDS THE AFT GALLEY. THEY SMELLED A BRIEF RUBBER, METALLIC SMELL. IT WAS CONSTANT VIBRATION UNTIL 250. THEN INTERMITTENT. DELTA MX HELPED TROUBLESHOOT IN AIR. WE TURNED THE L PACK TO STBY AND WE DIDN'T HAVE THE VIBRATION. CORRECTIVE ACTION: REMOVED AFT CARGO AFT WALL PANEL FOR INSPECTION. REMOVED FWD CARGO AFT WALL PANELS AND REMOVED RT RECIRC FAN TO BE REPLACED. C/W ODI CHECKLIST, FOUND AFT EQUIP VENT FAN 2 PRODUCING STRONG METALLIC SMELL AND HIGH VIBRATIONS. R&R AFT VENT FAN 2 PER B757 AMM 21-26. OPS CHECK GOOD. INSTALLED NEW RT RECIRC FAN PER B757 AMM 21-25. OPS CHECK GOOD. REINSTALLED CARGO PANELS PER B757 AMM 25-50. (9957564)