A Martha’s Vineyard ferry was taken out of service on Wednesday for up to a week because of a generator issue, just days after a power failure that stranded the vessel for five hours, the Steamship Authority said.

No passengers were on board the M/V Martha’s Vineyard when the generator issue occurred Tuesday night, spokesman Sean Gonsalves said. The power failure on Saturday night stranded 72 passengers, the authority said.

The authority said Saturday’s problem was caused by the main fuel oil transfer pump, which did not generate enough pressure to transfer fuel to the vessel. In addition to the passengers, 11 crew members and three food concession employees were on board.

On Monday, the authority said that the ship had undergone tests, passed Coast Guard inspection, and been cleared to resume service.

The ferry will undergo additional testing and repairs in Fairhaven with the help of the contractor who helped refurbish the boat before it returned to service on May 7 after an $18 million, five-month process, the authority said. It was already scheduled to return to the Fairhaven site in May for maintenance.

In the meantime, the authority said it would replace the Martha’s Vineyard with the Sankaty, a smaller vessel it typically uses to transport freight.

Delays in passenger traffic are not expected, but there may be delays in transporting vehicles because of the vessel’s smaller size.

“We apologize in advance for any inconvenience this may cause,’’ the authority said in a statement. “The safe and reliable operation of all Steamship Authority vessels is our highest priority.’’

Conrad Roy, owner of Tucker Roy Marine Towing & Salvage, said his company was escorting the ferry from Martha’s Vineyard to the Steamship Authority in Fairhaven because of “machinery problems’’ Wednesday morning.

“If they break down, we’re close by so we can help them out,’’ Roy said.

Laney Ruckstuhl can be reached at laney.ruckstuhl@globe.com. Follow her on Twitter @laneyruckstuhl.