Engine crankshaft front end sealing protection structure, engine assembly and vehicle

The utility model provides an engine crankshaft front end sealing protection structure, an engine assembly and a vehicle, and belongs to the technical field of engines, the engine crankshaft front end sealing protection structure comprises an air cylinder body, a crankshaft, a belt pulley and a front oil seal, the crankshaft is arranged in the air cylinder body, the belt pulley is fixedly arranged at the front end of the crankshaft, and the front oil seal is sealed between the air cylinder body and the belt pulley; the cylinder body is provided with an annular flange axially protruding towards the belt pulley; the belt pulley is provided with an annular boss axially protruding towards the cylinder body, the annular flange and the annular boss are axially opposite to form a first protection structure, a first gap is reserved between the annular flange and the annular boss, and the width b of the first gap is 2-2.5 mm. The annular boss and the annular flange are arranged on the periphery of the front seal in a