The Vaporizing Of Paraffin for High-Speed Motors
(Electric Ignition Type)

ROAD CAR AND TRACTOR MOTORS. 10<» jet. Again, in the largely increasing number of fuel-oil engines operating on the direct injection system, the fuel is sprayed into the cylinder by a compressed-air jet,, but in this case at a pressure exceeding a compression of 33 atmospheres. It would, therefore, only be con- sistent to presume that were it not for the difficulty experienced in the application of this principle, coupled with many inherent complexities involved in the pro- cess, this method would ere now have been adopted for automobile motors. The Stewart-Morris method of pressure injection is,, however, the nearest approach to air or mechanical pressure atomization as applied to high-speed motors up to the present. According to this vaporizing method, shown in Figs. 84 and 85, illustrating its application to a four-cylinder 20 H.P. ordinary touring car, the fuel will be seen to be sprayed under pressure and quite independently of suction eft'ect or fuel level, and that no float cistern is, therefore, required ; the starting and running fuels—petrol and paraffin—are supplied from separate tanks maintained at a pressure of 4 tö 6 Jbs.,. by an ordinary hand pump. The change-over from petrol to paraffin is effected by a pair of gland-packed plugs t; thence the fuel is automatically regulated by a vertical movement of the taper needle j within the spray nozzle, this needle being hinged on to the guide stem of the mixture regulator r. In action, primary air is drawn in by the motor pistons along the pipe a and across the fuel jet, which issnes in a continuous and attenuated angular stream ; the air thus carburetted is then drawn through the pipe v to the vaporizer v1, which, as shown, consists of a plain