Sarpedon was laid down as LST-956 on 11 July 1944, at Hingham, Massachusetts, by the Bethlehem-Hingham Shipyard; reclassified as a battle damage repair ship and named Sarpedon on 14 August 1944; launched on 21 August 1944; commissioned on 16 November 1944, for transit to the conversion yard; decommissioned on 29 November 1944, for conversion by the Maryland Drydock Company, of Baltimore, Maryland; and recommissioned on 19 March 1945.

Following brief stops at the Panama Canal Zone, San Pedro, Los Angeles, Pearl Harbor, Eniwetok, and Guam, Sarpedon arrived at Saipan on 2 July 1945.

[3] The Japanese surrendered on 15 August, but Sarpedon, plagued by a new enemy, the weather, continued to work in support of occupation forces.

Many craft were wrecked in the harbor, but Sarpedon's anchor held despite collisions with two barges and a PC which broke their moorings and crashed alongside.

[3] Laid up in the Pacific Reserve Fleet, San Diego Group, she was struck from the Naval Vessel Register 15 April 1976; sold for scrapping 1 January 1977, by the Defense Reutilization and Marketing Service (DRMS); and acquired by Phaethon Shipping & Trading Corporation S.A., Panama, and renamed SS Petrola 133.