What was found
SMOKE ODOR IN COCKPIT & CABIN DURING CRUISE AT FLT LEVEL 220. OPS BOTH PACKS WITH NO FAULTS. FOUND BOTH MUFFLERS TO HAVE TEARS & EVIDENCE OF BURNS. R & R BOTH RECIRC MUFFLERS. PERFORMED OPS CHECK OF PACK SYS. FAULT PERSISTS, RAN PACK 1 & 2 ON BOTH APU & ENGS INDIVIDUALLY. ODOR IS PRESENT WITH ONLY APU BLEED SELECTED. PERFORMED GVI OF PACK SYS 1 & 2. NO DEFECTS NOTED. REMOVED AND REINSTALLED CROSS BLEED VALVE FOR GVI. NO DEFECTS NOTED. FOUND APU LEAKING & CONSUMING OIL. PERFORMED OIL DECONTAMINATION. FOUND WHEN RUNNING PACKS 1 & 2 WITH ENG BLEED NO ODOR NOTED WHEN PACKS ARE OPERATED WITH APU BLEED SMELL PERSISTS. REMOVED AND REPLACED APU. OPS AND LEAK CHECK SAT. C/B E6 AND C30 RESET. OPS AND LEAK CHECK SAT.