In 1898 supposed to have been a first meeting between Armand Peugeot and Rudolf Diesel, one year after first run of his engine. It is much too large for Peugeots plan for usage in trucks. Anyway, the engine is mainly used in railways and especially ships for a long time.

Peugeot builds in Lille since 1928 two-stroke heavy-fuel (diesel) engines for boats, railcars, construction equipment and trucks under license from Junkers, after having tested in diverse own developments even with spark plugs since 1921.

The here presented four-stroke diesel engine from 1936, however, more thought for passenger cars, for which the manufacturer needs even a special permission of the state authorities. May be the company feels the competition of Mercedes with the 260 D. Both new engines run in heavy vehicle models and only in limited quantities eg for taxis.

The two engines resemble each other except the cylinder head. The in the HL 50 has swirl chambers according to the license of Oberhänsli. It seems to be the better concept as will become apparent in the further history of the diesel engine. It represents a better power delivery and less consumption, but from that is not much to feel in 1936. However, the HL 50 has also not the disadvantage of swirl chambers to be more noisy.