A small general purpose engine used mainly as a power source for agricultural machineries, under the circumstance of continuous operation at overload for a long time, must have two requirements which are (1) nonoverheating and (2) enough durability with good performance characteristics.
This study, from the viewpoint of issues mentioned above, has been achieved in terms of the following two purposes:
(1) To investigate problems on cooling and durability as well as measures, which should not deal with independently due to interacting each other, of the small air-cooled Wankel rotary engine.
(2) To provide both standard design parameters on cooling and durability, and materials for principal engine parts, which are required for the basic design.
This report discusses seveal issues as to (1) an axial flow air-cooling system of housings and (2) a charge-cooling system both to lubricate the needle roller bearings in an induction mixture passage and to cool the rotor with the mixture.