The Haru engines from early post-WW2 Japan are one of the least known Japanese model engine marques. Beginning almost immediately after hostilities ended, the production life of the range extended from 1946 up to the early 1960's. The designs produced ranged from small piston-port sparkies all the way up to large twin cylinder glow-plug models.

The Haru engines were designed by a certain Mr. N. Haruyama and were constructed to very high standards but in relatively small numbers in what appear to have been somewhat modest production facilities. All examples that I've tested have performed very well. Mr. Haruyama was also associated with the Sky Shark and Sky Queen engines, also made in Japan. I've convered those models separately.  

A full review of the Haru range, including bench tests of some models, may be found elsewhere on this website.