B767-300 and 300 ER
Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Other / Unknown
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Maintenance; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Procedure
Upon postflight; it was noticed that there was a large amount of oil from the left nacelle. The mechanics in ZZZ discovered that the service caps for the left IDG were left off allowing oil to escape for the duration of our ETOPS flight.
B767 Captain reported IDG service caps were not installed prior to ETOPS flight; allowing oil to leak out.