The Jiimaan ferry is only transporting vehicles because of a minor leak in a stern tube discovered Tuesday morning.
The problem was discovered during a test run.
The stern itself is airtight, and water is not gushing into the ferry, according to Owen Sound Transportation president Susan Schrempf.
She said the leak has since self-resolved, but still requires a technician's stamp of approval.
Passenger service is not disrupted, because people are being carried on the other boat -- the Pelee Islander.
A technician has been called to repair the leak and should arrive in Leamington at 4:30 p.m., said Schrempf.
She said it should take a few hours to fix, and if all goes as planned, she predicts the Jiimaan will resume full service Tuesday at around 5:30 p.m.
The Jiimaan had been out of service since Oct. 11, when the ferry became stuck on a sandbar near Kingsville.