An Air Canada Boeing 737 MAX 8 aircraft is being towed in as another Air Canada Boeing 737 MAX 8 aircraft is seen on the ground at Toronto Pearson International Airport in Toronto, Ontario, Canada, March 13, 2019.Chris Helgren | ReutersA Montreal-bound Air Canada Boeing 737 Max ferry flight diverted in Arizona earlier this week due to an engine issue, the airline said Friday.Pilots on Air Canada Flight 2358 received an engine warning shortly after takeoff from Marana, Arizona on Tuesday, the airline said. The carrier had been storing 737 Max jets there after the planes were grounded worldwide in March 2019 after two deadly crashes. “As part of normal operating procedures in such situations, decided to shut down one engine” and diverted to Tucson, Air Canada said. The flight was carrying three crew members and no passengers. The plane remains in Tucson.Boeing declined to comment and referred questions to the airline.Belgian aviation site Aviation24.be said the plane had a “hydraulic low pressure indication.” Air Canada didn’t immediately respond to further request for comment.U.S. authorities lifted their ban on the planes last month after Boeing made changes to software that was implicated in both crashes, and addressed other concerns. Canadian officials last week approved design changes to the planes.