MV Isle of Lewis is not expected back in service until next weekend due to a delay in returning to Liverpool.
A CalMac spokesman said on Friday that plans to relocate the ferry back to Liverpool for repairs had been delayed due to the availability of a dry dock.
Specialist engineers travelled to Ullapool last week to carry out investigations in the hope of repairing the fault in situ, however this was not possible.
She arrived in Liverpool yesterday (Sunday) for repairs to begin this week.
The spokesman said: “We cannot say for certain when she will be back but would hope it will be no later than next weekend, and may possibly be sooner, although that is clearly subject to the successful completion of repairs etc. The MV Isle of Arran will continue to cover the service, and although we recognise this is not ideal, would stress that our options are very limited and we apologise for any inconvenience caused.”