[1] For surface running, the boats were powered by two 475-brake-horsepower (354 kW) NELSECO diesel engines, each driving one propeller shaft.

K-3 joined 3rd Submarine Division, Pacific Torpedo Flotilla 11, December 1914 and operated along the California coast developing underwater warfare tactics and coordinating the use of underseas craft with the fleet.

She arrived in Hawaiian waters 14 October 1915 to perform similar exercises in the light of increasing emphasis on submarine warfare.

The United States's entry into World War I placed a greater urgency on the need for experienced submariners, and K-3 was dispatched to Key West, Florida, arriving 8 January 1918.

K-3 continued operations along the East Coast after the war, testing new devices such as listening gear, storage batteries and torpedoes.