Device for rapidly fi lling the cooling system of cars and trucks. The system works by vacuum, and allows a rapid and total fi lling of the cooling system without any need to start the vehicle several times during the fi lling operations. Vacuum is generated using compressed air. When a cooling system is fi lled with liquid, air bubbles are generated, and these must be completely eliminated. Radiator fi ll suits both cars and lorries. Together with the kit, 3 different size cones are supplied to fi t different radiator. The device works on a system previously freed from any liquid, and allows also tightness test.