SMooth operatoR

By 1972 Mazda was gaining ground around the globe. While still offering conventional piston-engined cars it was seeking to establish rotary engines as the way of the future and these were powering a wide range of vehicles from cars through to buses. They were small, light, and powerful, if commensurately thirsty — getting something for nothing was beyond even the brilliant Mazda engineers — but they had one other advantage: their small engine capacities meant that they slotted into cheaper purchase tax categories in their large home market and some overseas markets.

Mazda bought a licence to develop and manufacture the Wankel engine in 1961, the revolutionary way to ingest, squish, and expel the fuel–air mixture 1961

Mazda bought a licence to develop and manufacture the Wankel engine in 1961. The revolutionary new way to ingest, squish, and expel the fuel–air mixture was invented by Felix Wankel in 1957. Mazda’s first version of the new power plant appeared in the Mazda Cosmo in 1967.

Those early engines were beset with wear problems that broke German carmaker NSU. Citroën also lost its shirt on its version, which powered the short-lived Citroën GS Birotor — see New Zealand Classic Car Issue No. 366, June 2021. Many other carmakers also licensed the tech including Alfa Romeo, American Motors, Ford, General Motors, Mercedes-Benz, Nissan, Porsche, Rolls-Royce, and Toyota, although the combination of technical challenges and the fuel crisis forced most to put the project on the back-burner. Norton and Suzuki however went on to produce rotary-engined motorcycles.

PERSISTENCE PAYS OFF

The big issue was vibration in the rotor edge seals which damaged the housing causing ‘chatter marks’. The resultant poor seal caused excessive oil consumption and loss of power. The