Edgar was recommissioned in December 1763 under the command of Captain George Collier to serve as the guardship at Plymouth, which role she undertook from February 1764. On 4 January 1765 she briefly sailed to the coat of Africa, but by the following year she had returned to her role at Plymouth. Captain Robert Carpenter took command from Collier in 1767, and he was in turn replaced by Captain the Honourable Henry St. John in 1771. Edgar was paid off by St. John in June, and she underwent a survey on 30 July. As a result of this it was ordered that Edgar was to be converted into a breakwater for Sheerness Dockyard on 23 March 1774.[2] The conversion was completed at Chatham Dockyard and Edgar was sailed to Sheerness on 8 June, from where she was sunk in place in August. Her remains were broken up in 1775.[2][1]