HEAVY oils, from their very nature, are suitable for use by the Diesel method. The higher pressures of the Diesel cycle necessitate only an inconsiderable increase in engine weight, according to Dr. Riehm, which does not interfere with its use for automotive purposes.
Of the various ways of carrying the Diesel cycle into practice, the Maschinenfabrik Augsburg-Nürnberg has adopted the pressure-atomization method which, because of its great simplicity, is particularly adapted to use in automotive engines. The construction of both the earlier and the most recent M. A. N. oil engines is described, with details of fuel injection and control. Test results under various conditions are shown in curves, and operating characteristics and experience are recounted.
Economy and flexibility are found to make the Diesel engine a recognized competitor of the gasoline engine for vehicle propulsion, especially where fuel cost is one of the major items of expense.