What was found
CREW REPORTED POST V1 & JUST INTO ROTATION, MASTER CAUTION ILLUMINATED FOR LT OIL PRESSURE LOW. DECISION MADE TO LEAVE MLG DOWN. OIL PRESSURE LOW & QTY DECREASING, NORMAL CHECKLIST COMPLETED & ABNORMAL CHECKLIST LEADING TO A PRECAUTIONARY SHUTDOWN. CREW ELECTED TO CONTINUE WITHOUT SHUTTING DOWN ENGINE. LANDED WITHOUT INCIDENT. NR 1 ENGINE SHUTDOWN PERFORMED ON GROUND. FOUND NR 1 ENGINE OIL LINE BETWEEN OIL COOLER & TOP OF GEARBOX HAD SEPARATED CAUSING LOSS OF OIL PRESSURE & QUANTITY. ENGINE REMOVED & REPLACED. INSPECTION OF OIL LINE REVEALED FERULE ON END OF LINE HAD COME LOOSE ALLOWING LINE TO SEPARATE. OIL LINE APPEARS TO HAVE BEEN SPRUNG (DISTORTED).