The Isle of Man Steam Packet Company's flagship vessel, Manxman, will remain out of service until at least late September after engineers discovered additional wear during its scheduled dry dock maintenance.

The ferry operator confirmed on Tuesday that inspections carried out after the vessel's propulsion shaft bearings were removed revealed wear to both the shaft bearings and associated shaft liners.

The company said the components could not be inspected until the disassembly process had begun, with the findings allowing specialist engineers to determine the full scope of repairs now required.

Shaft liners are protective components designed to absorb wear and safeguard the vessel's main propulsion shafts.

Specialist repair and machining work is now under way, but the Steam Packet says the complexity of the repairs, together with the availability of dry dock facilities and the need to source specialist parts and engineering support from suppliers in the UK and Europe, means the vessel is not expected to return to service until late September.

In a statement, the company said: ‘This is of course hugely disappointing news for our customers, however the Company's overriding priority is focused on working with the specialist engineers to complete these essential repairs safely and to the highest standard, ensuring Manxman's long-term reliability and performance.’

At the time, the Steam Packet did not disclose the nature of the repairs, prompting calls from some customers for greater transparency and sparking speculation over the scale of the issues affecting the three-year-old vessel.

To maintain services while Manxman remains out of action, Ben-my-Chree will continue operating all Heysham sailings, while the Arrow, which arrived on the island on Tuesday, will provide additional freight capacity on UK routes.

The company said its reservations team would continue working with customers affected by vessel changes or any necessary cancellations.

Passengers impacted by timetable changes will be contacted directly and advised of the travel options available to them.

The Steam Packet added: ‘The Isle of Man Steam Packet Company would again like to apologise for the disruption caused to customers and thank them for their continued patience and understanding while these essential repairs are completed.’

Isle of Man Today has approached the Steam Packet for clarification on why these issues have occurred so early in Manxman’s service life and whether the vessel remains covered by warranty.