Maintenance Powerplant; Maintenance Airframe
Troubleshooting; Situational Awareness; Communication Breakdown
Aircraft Equipment Problem Critical
Flight Crew Returned To Departure Airport; General Maintenance Action
Procedure; Manuals; Aircraft; Human Factors
October 2012; I was assigned to work a B767-300 aircraft that had a Maintenance entry of a # 1 Engine Oil Pressure Indication problem. I found the Oil Press Transmitter faulted. We replaced the transmitter per Maintenance Manual (M/M) and accomplished an [oil] Leak Check as required by the M/M. The flight crew ran the engine on the gate and no leaks were noted. I was made aware that this aircraft had a flight interruption and returned to ZZZ with a problem with engine oil loss in flight.
Reporter stated the oil loss was found at an oil line elbow fitting further down from where he replaced the Oil Pressure Transmitter on # 1 Engine. He recommends a higher power setting when performing Oil Leak Checks because the Idle Power run settings at the gate are not sufficient to determine whether or not if leaks will occur.
A Line Mechanic reports a B767-300 aircraft returned to departure airport due to engine oil loss in flight.  He had replaced the Oil Pressure Transmitter on # 1 Engine prior to departure.