Much before refined diesel was stringently controlled by EPA norms and international agencies, there was raw or crude diesel. Much before sleek diesel engines, there were large, rather odd looking engines that were primarily tasked for function and not for comforting or fluidic designs of the vessels. One of the finest masterpieces of such diesel engines can be explored in the WWII Balao Class Submarine.
When the Second World War was inching towards an end, the navies of the Allied Forces needed more dominating and powerful presence in the waters and under. Thus, one needed submarines that could be in the waters for a long time and often in troubled enemy waters. For such operations, one needs an engine, rather a power plant that is reliable and has enough jus to last the mission.
The USS Pampanito (SS-383) was the first of its kind boat built which could store 110,000 gallons of diesel. There were several such submarines built from 1942 through 1944 which formed the Word War II Balao Class Fleet.
The USS Pampanito had 4 Fairbanks Morse 38D 8 1/8 model motors, which used opposed piston, in-line 10-cylinder engine with a bore of 8 1/8 inches and a stroke of 10 inches. Each ship had an auxiliary engine, the Fairbanks Morse Model 38E 5¼, which was a 7-cylinder, opposed piston, air-starting engine rated at 440HP with a bore of 5 1/4 inches and a stroke of 7 1/4 inches.
While operating at the surface, the submarine had two diesel engines driving the motor generators and two more powering the batteries. There was a fifth engine to provide electrical power for the auxiliary equipment onboard and the lights. The engines could operate at 300 rpm with peak performance clocking at 400 rpm.
The most stunning feature of the USS Pampanito was the ability to store 110,000 gallons of diesel for the five engines. To make this possible and to make the technology work, the ship had a bunker with a centrifugal purifying system. The Fairbanks Morse 38D 8 1/8 engines could generate 1600 horsepower.
Fascinatingly, despite the technology being almost seventy years old, Fairbanks Morse still manufactures spare parts for the engine as the engine had been in widespread use for many years after the war, well into the eighties.
Presently, the USS Pampanito is at pier 41 at the San Francisco Maritime Museum.