As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE NR 1 ENGINE IDG HAS A HISTORY OF FREQUENT OIL SERVICING. 2 IDG'S HAVE BEEN CHANGED FOR THIS REASON. ALSO EXTERNAL COOLER EXAMINATION REVEALED NO EVIDENCE OF EXTERNAL LEAKAGE. ACFT GROUNDED. R & R NR 1 ENGINE IDG OIL COOLER IAW AMM 73-11-06-000-801 AND 73-11-06-400-801.