Carburetter piston clatter on a Corniche model and the reasons for modifying the spring-loaded plungers.
| Identifier | ExFiles\Box 97\3\ scan0200 | |
| Date | 25th July 1939 | |
| H009. To Rm {William Robotham - Chief Engineer} /IMW. {Ivan M. Waller - Head of Chateauroux} from Rm {William Robotham - Chief Engineer} /CTS. {C. Trot Salt - Carburation} Hotel de France, Chateauroux(French test region), Indre, France. Rm {William Robotham - Chief Engineer} /CTS. {C. Trot Salt - Carburation} 5/MH. {M. Huckerby} 25.7.39. 14.B.V. - CORNICHE(Bentley streamline(Experimental Streamline Bentley B.23.A.E)d precursor to R Type Continental, never produced). With reference to the carburetter piston clatter complained of in your memo dated 22.7.39. The spring loaded plungers were purposely pressed back out of action by Ratcliffe, in order to obtain an unbiased opinion of their value. By using a small drift behind these plungers on the inside of the pistons, they can be tapped back on to their stops to resume their normal function. The reason for all this is as follows:- There is a slight advantage in having the pistons right down on the bridge for cold starting, because a greater suction is exe(Aero Engine)rted on the starter carb., and consequently there is a quicker response. The difference will be noticed in the number of revs. the engine does on the starter button before firing. We would be glad to have your opinion, directly comparing - (a) The value of the plungers in and out of action, against (b) the effect on cold starting, with the plungers, in and out of action. Finally, we would say that this job is in no way connected with the alteration to the hydraulic dampers, as they have a certain free movement anyway, which has been about doubled on the Corniche(Bentley streamline(Experimental Streamline Bentley B.23.A.E)d precursor to R Type Continental, never produced) carburetters. Rm {William Robotham - Chief Engineer} /CTS. {C. Trot Salt - Carburation} | ||
From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).