The vessel got into difficulty shortly before 20:30 just south of Noirmont Point.
Pictured: The motorboat was in the area of Noirmont Point.
Explaining the sequence of events, the Jersey Fire and Rescue Service said on Facebook: “Both the Services Inshore Rescue Boats were in the area on a training exercise and were on scene within five minutes.
“One Fire crew member was placed on board the casualty vessel to assist the people on board.”
They added: “The vessel made its own way into St Helier Harbour with both the Services Inshore Rescue boats standing off in case assistance was required, with other private vessels that had come to help.”
Islanders have since praised the crew’s quick actions, with one commenting: “Well done! What good timing you could get there so quickly.”