PURPOSE: To improve durability of a connecting place of a stay and a radiator by fixing a base end part of the radiator to the stay, drawing a horizontal arm to the front side from the stay, and supporting the radiator with this horizontal arm from the under side.

CONSTITUTION: A fan case 3 covering a cooling fan 2 is arranged in front of an engine body 1, and an air blowoff port 4 is bored in an upper surface of this fan case 3, and a radiator 5 of engine cooling liquid is arranged above this air blowoff port 4. A base end part 6 of this radiator 5 is fixed to a stay 7, and the radiator 5 is installed in front of the engine body 1 through this stay 7. A horizontal arm 8 is drawn to the front side from the stay 7, and the radiator 5 is supported with this horizontal arm 8 from the under side. Besides a load of the radiator 5 is borne even by the horizontal arm 8, a vertical swing width of a front end part 14 of the radiator 5 becomes smaller than suppressing force of the horizontal arm 8. In this way, durability of a connecting place of the stay 7 and the radiator 5 can be improved.