What was found
TEN MINUTES PRIOR TO TOP OF DESCENT BOTH PILOTS SMELLED A BURRING PLASTIC SMELL WHICH CONTINUED THROUGH MOST OF THE DESCENT. WE HEARD A SLIGHT WAILING NOISE JUST PRIOR TO THE SMELL. C/A: STARTED TROUBLESHOOTING PER AMDS WORK CARD 0550-2002. INSPECTED COCKPIT INSTRUMENT PANEL, CIRCUIT BREAKER PANELS, FWD LAVATORY WITH NO DEFECTS NOTED. FOUND 18HQ EXTRACT FAN EXTREMELY HOT & NOISY ALSO A SLIGHT SMELL. R & R 18HQ REF AMM 21-26, OPS CHECK GOOD. ALSO FOUND FWD GALLEY OVEN WHEN ON EXTREMELY SMELLY. R & R FWD GALLEY OVEN REF AMM 25-35. PRECAUTIONARY PRESSURIZED AC TURNED ALL ELECTRICAL SYSTEM NO ODORNOTED. CONFERENCE CALL WITH MCC ACCOMPLISHED. WORK CARD 0550-2002 ACCOMPLISHED OK FOR SVC. (LP: 9113302, AIRCRAFT WAS GROUNDED)