What was found
(CAN) THE CREW REPORTED A METALLIC SMOKY SMELL IN THE CABIN AT ROTATION. ON CLIMB OUT, SMOKE BECAME APPARENT IN THE CABIN. THEY SHUT DOWN THE PAC & OPENED THE RAM AIR. DECLARED AN EMER & RETURNED TO BASE. THE SMOKE WAS CLEARING OUT PRETTY GOOD BY THE TIME THEY LANDED. IT WAS AN OVERWEIGHT LANDING DUE TO THE FUEL LOAD ON BOARD. . CONFIRMED THE ACM FAIL. WE ARE REPLACING THE ACM & ASSOCIATED SEALS, DOING AN OVERWEIGHT LANDING INSPECTION.