The Mark 8 remained in service through World War II on older destroyers, primarily the Wickes and Clemson classes.

It also equipped PT boats early in World War II, but was replaced by the Mark 13 torpedo on most of these in mid-1943.

This was a problem in the South Pacific, where the humid climate would cause these charges to misfire, sometimes not putting enough force behind the torpedo to fully eject it from the tube.

Though the warhead could not detonate, the motor would overheat and explode without water to cool it, sending splinters across the deck.

Sometimes during launch, the charge would ignite the lubricants in the tube causing a fire emitting black smoke that would reveal the location of the torpedo boat.