Crossing times for the Steam Packet fastcraft Viking will be increased to three hours while vital repairs are carried out.
One of the vessel's four gearboxes failed at the weekend, and it's expected to take up to three weeks to remove, strip down and rebuild it.
The company's Chief Executive Mark Woodward says the offending component was given a thorough internal inspection last winter, so its failure is disappointing.
The Steam Packet is aiming to maintain existing departure times but has cancelled this Thursday's 7.30am return sailing to Liverpool to allow for the gearbox to be removed.
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