The vessel initially operated on the round-the-world route from the West Coast of the United States via East Asia and Spain before being shifted to serve the Gulf to Europe and South America trade in 1922.

[4] The vessel also possessed all the modern machinery for quick loading and unloading of cargo from five large hatches, including ten winches and eleven booms.

[20] Following successful completion of a round the world scout trip through East Asia and the Mediterranean by West Kasson, Pacific Mail Steamship Co. decided to expand this service adding more vessels to the trade route.

She left Baltimore on September 4 and after passing through the Panama Canal arrived in San Francisco on 4 October 1920 successfully completing another round the world journey covering more than 28,000 miles in the process.

[24][25][26] West Kasson made one more round-the-world journey while under control of the Pacific Mail Steamship Co., returning to Baltimore on 11 March 1921 to discharge approximately 1,000 tons of manganese ore.[27] On 10 April 1921 it was reported that the Pacific Mail Steamship Co. decided to return four large vessels, including West Kasson, to the Shipping Board citing lack of cargo in all of their foreign ports of service.

[30] After taking on board nearly 2,700,000 feet of fir and cedar lumber, West Kasson departed Portland on 5 July 1921 bound for Japanese ports of Kobe and Yokohama.

[31] Initially, the freighter was supposed to return directly to the West Coast, however, upon arrival in Japan at the end of July the vessel was rerouted to Singapore resulting in another round-the-world trip.

[32] West Kasson departed London for New York on 29 November 1921,[33] however, on her way back 'she lost her propeller and was forced to put in into Bermuda on December 18 for repairs.

After reaching New Orleans on February 22, West Kasson proceeded to load general cargo in several Gulf ports and cleared from Charleston on 5 April 1922 bound for Antwerp and Havre.

She mostly carried cotton, wheat, case oil, phosphate rock and lumber on her transatlantic travels to Low Countries, usually returning home in ballast.

For example, the freighter left Brazilian ports of Rio de Janeiro, Santos and Vitória at the end of July 1924 carrying nearly 70,000 60-kilogram bags of coffee to New Orleans.

[44][45][46] Early in 1925 the vessel returned to her travels to France and Belgium and sailed from New Orleans on 1 February 1925 fully laden with wheat, lumber and case oil bound for Le Havre and Antwerp.

The ship suffered heavy damage amidships and had her entire engine room flooded, however, most of her cargo of wheat remained undamaged and was safely unloaded once the fire was completely extinguished.

[57] The vessel then continued to Tacoma where she arrived on August 23 to discharge ore for the local ASARCO smelter, successfully concluding her first full trip under new ownership.

On December 6 while being off the southern coast of Mexico, West Kasson sent out a distress signal stating that she had fire in one of her forward holds but not requesting any assistance.

[62] West Kasson safely reached San Pedro ten days without any signs of damage, and later proceeded north to load more cargo for South America.

Cuzco was the first vessel to have such machinery installed in November of the same year, allowing her to carry approximately 250 tons of perishable goods, such as dairy products and produce.

For example, in September 1933 the vessel delivered about 24,000 pounds of aerial bombs destined for the Armed Forces of Honduras and El Salvador, and in November 1934 she brought back approximately 500 tons of sulfur from South America to San Pedro.

On 27 October 1935 while on one of her regular trip from San Pedro to Valparaiso, the ship went aground on Lempa shoals in Jiquilisco Bay on El Salvador's Pacific coast.

[84][85] Both tugs arrived on the scene in early November and after an inspection determined the vessel's hull was intact, an attempt to refloat the grounded steamer was made.

The burning was fueled both by sulfur and treated ore concentrates and was threatening to get out of control and destroy the ship, however, the firemen were able to deploy two fireboats in time to quickly extinguish the blaze.

[87] Late in 1939 the Maritime Commission (MARCOM) offered W. R. Grace to put three modern Type C2 vessels in operation between the West Coast and South America.

Instead, in March 1940 it was announced that W. R. Grace agreed to sell three of their vessels, Cuzco, Capac and Charcas to a Panama-based Compañía de Vapores Cardina, S.A, a subsidiary of Belgium-based Compagnie Continentale d’Importation.

[89][90] At the time of sale Cuzco was on her regular journey to Central and South America transporting her usual cargo including five Arabian horses bought by the government of Colombia.

[91] After loading her usual cargo of nitrates and copper and vanadium ore the vessel passed through the Panama Canal on May 5 and continued to New York where she was transferred into Panamanian registry.

At 11:27 local time on July 18, 1942, in position 10°58′N 61°20′W / 10.967°N 61.333°W / 10.967; -61.333, southeast of Trinidad, German submarine U-160 under command of Georg Lassen launched four torpedoes and hit Carmona on the starboard side.

The Master ordered to abandon ship and the survivors were picked up by a United States Navy Patrol Boat USS YPC-68 and taken to Port of Spain.