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).
Solutions for engine stalling on the Phantom III during clutch engagement.
| Identifier | ExFiles\Box 93\3\ scan0391 | |
| Date | 2nd October 1937 | |
| 312. Rm{William Robotham - Chief Engineer}/FD.{Frank Dodd - Bodies} from Rm.{William Robotham - Chief Engineer} Rm{William Robotham - Chief Engineer}/NRC.{N. R. Chandler} Rm{William Robotham - Chief Engineer}/GR.{George Ratcliffe} Rm{William Robotham - Chief Engineer}9/R.2.10.37. STALLING OF P.III ON CLUTCH ENGAGEMENT. This has always been a very bad feature of the P.III. At the present moment it is preventing us intro ducing the servo spring on the clutch pedal. We believe that there are three ways of tackling this problem:- (1) By improving the clutch engagement. This may mean alteration to the cushioning springs, and also probable reduction in the clutch spring pressure, i.e., running the clutch nearer the slipping mark. (2) Increasing the flywheel inertia. We have already tried this when we ran the flexible flywheel and obtained good results. There is, however, obviously a limit to the amount of inertia we can put on the flywheel, and the car is already too heavy. (3) Carburation. There is not the least doubt that stalling at low speeds is accentuated by any flat spot in the carburetter. It may be that we are trying to run the P.III at too low an idling speed. We do not wish to run our cars at a lower average speed than the American car. Experiments should be con ducted to determine whether if we altered the carburetter characteristics we could reduce the tendency for the P.III to stall when the clutch is engaged. We might also try alter ing the timing by varying the tappet clear ances and small induction pipes. Rm.{William Robotham - Chief Engineer} | ||