The Ben my Chree will go into dry dock after the busy TT period for repairs to a damaged bow thruster.
Specialist contractors have been booked to remove the component next weekend, between June 18 and 20.
It will be reinstalled later in the year, after the busy summer season.
On Saturday, June 18 the Ben will sail from Douglas to Birkenhead 12 Quays for the period in dry dock.
Her scheduled sailings that weekend have been cancelled and passengers transferred onto the Manannan services between the Island and Liverpool. A freighter has been chartered to carry the Ben's freight.
The early-hours crossing from Heysham on Monday, June 20 will be operated by Manannan, with the sailing a little later than usual, at 3am.
The Ben is due back in service later that day, sailing from Birkenhead at 3.15pm.
Passengers booked on the Ben that weekend have been contacted and offered alternative sailings or a refund.
The Steam Packet says docking without one of the two bow thrusters in bad weather can be tricky, and a tug will be used to help if required.
The Ben my Chree's round the Island trip has been postponed until July 2.