Engineers will begin work on the Ben-my-Chree today in a bid to fix an "unexplained vibration" which is coming from the propeller.
The boat will spend the next two days in dry dock - the Steam Packet Company has described the process as a "precautionary inspection":
Contingency plans are in place to cover the vessel's absence - it's hoped it will return to service on Thursday morning.
Chief executive Mark Woodward says due to the close proximity of the TT period the boat must be reliable:
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