What was found
(AIRCRAFT 6801, L/P 3751740) VERY STRONG WET SOCK SMELL FROM AIR CONDITIONING SYSTEM ON APPROACH. PERFORMED BSI OF THE 2.5 BLEED PORT FINDINGS TURNED OVER TO LEAK AND MCC. FOUND EVIDENCE OF OIL CONTAMINATION IN 2.5 BLEED PORT AREA R/R LT PACK OZON CONVERTER PER B757 AMM 21-51. R/R BOTH RECI/FAN FILTER PER B757 AMM 21-51. ENGINE REMOVED IAW JIC 7100-9902E-01. ENGINE INSTALLED PER B757 AMDS WORKCARD 7100-9902E-01. RII COMPLETED AND PREFLIGHT C/W PER AMDS WORKCARD 7100-9902E-01.