B737 Undifferentiated or Other Model
Situational Awareness
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy
General Maintenance Action
Human Factors; Procedure
I was checking the oil on the APU for our service check. I removed the cover and set it down on the lift. While I was visually checking the APU oil level; my Lead came to me and was asking questions about a sheet metal reinspect (that) I had done. During our conversation; I verified the oil level was good and reinstalled the cap. I proceeded to close the cowling up and left the work area. The man lift I was using had a low battery so it added a further level of distraction to the process. It was brought to my attention 2 nights later that the cover was found and it had been verified that the oil cap cover was missing from the aircraft.
A Maintenance Technician reported that after checking the APU oil on a Boeing 737 he neglected to reinstall oil cap.