The Tamar-class George Sullivan lifeboat, based in St Helier, has had recurring problems with its port engine which have not been able to be fixed locally.
Last week, the vessel was taken back to Poole, where it is to have the engine replaced. It is expected to be out of service for several weeks.
The RNLI has sent a replacement Tamar-class all-weather lifeboat to Jersey to provide cover until the George Sullivan returns.
