Four people were on board the helicopter when it crashed on 14 March.
Winch operator Paul Ormsby and winch man Ciaran Smith are still missing.
A statement was released on Saturday by the Air Accident Investigation Unit (AAIU) after an examination of the helicopter's data systems.
"Following an event such as this, many operators and agencies are anxious to learn if any matters are identified during the ongoing investigation that may require immediate safety actions," the statement said.
"An initial analysis has been conducted of the data retrieved from the helicopter's Health and Usage Monitoring System (HUMS) and the Multi-Purpose Flight Recorder (MPFR). No mechanical anomalies have been identified during this initial analysis."
The AAIU said the investigation is ongoing and a preliminary report will be issued in the near future.
The most senior pilot on board the aircraft, Cpt Dara Fitzpatrick, died after she was rescued from the sea hours after the crash.
The body of her co-pilot, Capt Mark Duffy was later recovered from the wreckage.
Efforts to lift the wreckage of R116 have been delayed again on Saturday due to rough sea conditions around Blackrock Island.
At the time of the crash, the R116 crew were providing communications support to another Irish Coast Guard helicopter, which had been deployed to airlift an injured fisherman to hospital.
The main part of the wreckage was located last month about 60m west of Blackrock island, but difficult weather conditions have hampered the recovery operation.
The aircraft is lying on the seabed at a depth of about 40m.
About 80 members of the Irish Defence Forces, including air corps and army personnel,  have been deployed to assist the multi-agency operation in Blacksod Bay.
Irish air accident investigators say initial indications are that there was no mechanical failure in the moments before Coast Guard Rescue Helicopter R116 crashed off the County Mayo coast.