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

VAPORIZATION IN THE HIGH-SPEED MARINE ENGINE. 65 cylinders through passages n.n1; the level of the fuel in the spray nozzle is controlled by a cistern t containing a float-valve supplied under the necessary pressure, with fuel along f from the storage tanks. According to this system, the motors have eight cylinders, each capable of developing from 30 to 45 and each set of four have a separate vaporizer. In the Parsons marine motor, the paraffin vaporizer will be seen to take the form more of a carburettor than other vaporizers of the exhaust-heated type, the reason for this being that in this make the partially vaporized mixture is distributed to each cylinder in turn through a large ring or hollow admission valve, which forms the seat for and carries with it the exhaust valve ; con- sequently, therefore, the annular space surrounding the passage for the exhaust gases serves also as a vaporizing chamber, and indeed motors fitted with this form of combined admission and exhaust valve * are capable of running on paraffin af ter a preliminary run with petrol for a sufficient time to get the motor thoroughly warmed up to its work. However, motors of this make, when intended more particularly for being worked with flash-proof oils, such as the several grades of the paraffin series, are provided with a simple form of vaporizer. as illustrated in Fig. 45, in which the jacket v surrounding the exhaust manifold x1 with branches x to the cylinders, constitutes the vaporizer, whence the mixture after passing through a hollow ping regulator h, is diluted with an additional supply of air along the pipe s also under Control, before entering portways n leading to the admission valves. Starting and running fuel is supplied to a pair * Illustrated in “ Carburettors, Vaporizers, and Distributing Valves.” 5