In 1932 there was a proposal to convert some of the locomotives to diesel power. The
prime mover would have been an 8-cylinder
diesel engine of 400 horsepower, driving a 4-cylinder
air compressor to charge an air reservoir. Compressed air from the reservoir would have been heated, both by the diesel exhaust and by steam from an oil-fired
steam generator, and would then have entered the locomotive's original cylinders at about 150 psi. The use of steam to heat the air is reminiscent of the
Mekarski system. This diesel-pneumatic proposal never became a reality but a German one of 1929 did. ==Withdrawal==