Small general engine and cooling structure thereof

The utility model discloses a cooling structure of a small general engine, which comprises an impeller, a flywheel, a cylinder head fairing and a crankcase body, and a plurality of groups of radiating ribs are arranged on the upper surface and/or a base of the crankcase body; each group of radiating ribs comprises two edge radiating ribs which are respectively arranged on two sides and a plurality of middle radiating ribs which are positioned between the two edge radiating ribs; the whole radiating ribs are distributed in an involute shape, such as a fan shape, a C shape or an L shape. Therefore, cooling air sucked by the impeller of the engine can be reasonably distributed to each part of the crankcase, so that more surface area of the crankcase can be cooled; in addition, the overall strength of the crankcase is enhanced. The small-sized general engine has the corresponding advantages which are not repeated any more. 本实用新型公开了一种小型通用发动机的冷却结构，包括叶轮、飞轮、汽缸头导流罩以及曲轴箱体，所述曲轴箱体的上表面和/或底座设有多组散热筋；各组所述散热筋均包括两条分列两侧的边缘散热筋，以