At 18.52 hours on 18 May 1942 the unescorted San Eliseo was hit on the starboard side under the bridge and amidships by two torpedoes from U-156. The tanker had been spotted five hours before and continued after counter-flooding, firing into the direction of the U-boat, which surfaced and tried to get into a new firing position. At 04.39 hours on 19 May, a third torpedo was fired that hit on the starboard side aft of the bridge but apparently only caused minor damage because the tanker still continued. Even a fourth torpedo hit at 07.39 hours on the starboard side near the engine room could not stop her. At 09.17 hours, a stern torpedo was fired at the ship from the port side but missed because the tanker zigzagged wild from 120° to 330°. The U-boat had finally to give up the chase because it was ordered by the BdU to set course on Martinique immediately and the chance to score another hit on the alarmed tanker was very small.

The San Eliseo arrived at Barbados on 20 May for temporary repairs, later continued to the USA where she returned to service after permanent repairs were made.