Technicians reported communications issues lead to an aircraft being dispatched in revenue service without the required engine oil leak checks being performed. The aircraft experienced an in flight shut down and diversion to a precautionary landing.
Synopsis
Technicians reported communications issues lead to an aircraft being dispatched in revenue service without the required engine oil leak checks being performed. The aircraft experienced an in flight shut down and diversion to a precautionary landing.
Narrative
I was given as part of the work package for Aircraft X; a job to replace packings on #2 ENG chip detector housing as the seals on the actual detector had already been replaced by swing shift. When I took the housing out of the body. I found the tech data I had been given as well as the packings did not match the parts I was looking at. I told my Crew Chief and he came down and tried to make what we had work but could not. We decided to look at #1 ENG chip detector so we dropped the chip detector from the sleeve and looked up into the valve and saw it was a completely different set up with the rubber seal missing from the #2 ENG check valve. The Crew Chief ordered complete valve body assembly to come in later in the day. Everything was put back together and at morning turnover Crew Chief told Lead Crew Chief what we had done and that both engines will require leak checks. I am not sure what happened; if the engines passed leak check and later failed or the leak check was overlooked because there was no log entry. I feel sick about it either way and wish I had it to do over again.Either the leak check was done and it passed only to fail later or it was overlooked by the next shift because there was no log entry only a verbal turnover.Everything must be documented.
Second reporter narrative
Aircraft X diverted to ZZZ on Date; due to left engine low oil Qty. Oil leak source was the left engine EMCD (Electro Magnetic Chip Detector). Repair was accomplished replacing the debris monitoring unit/Assy. Prior to this event; Aircraft X was out of service in ZZZ1 due to right engine oil leak. 1st and 2nd shift troubleshot isolated the oil leak to EMCD (Electro Master Chip Detector); and an ordered O-ring. I was a Crew Chief. After receiving the parts I did assign 3 AMT to Aircraft X to work the oil leak and assigned BOW (Basic Operating Weight). I was called to the Aircraft because the O-rings did not match. I had on hand the co-ordinate measuring machine reference that was printed earlier by the Crew Chief and tried to figure out why its different. A suggestion was to check the other side (left engine) for confirmation the EMCD was removed and installed. I did go back to the office to research and found that we have 2 different configurations for the EMCD and continued with ordering new parts and other workload. At the end of the shift; I gave a verbal turn over to the Crew Chief. We also told the Crew Chief who's was taking over to leak check the left engine. I was not aware it wasn't documented in the AML. This event would have been prevented if all work and the required EMCD leak check was documented on the AML. And written turnover was given. (Following procedures).
Source: NASA Aviation Safety Reporting System (public domain). Reports are voluntary submissions and are not verified by NASA.