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).
Vapour lock investigation, the merits of mechanically operated vs. electrical pumps, and flywheel inertia on overdrive models.
| Identifier | ExFiles\Box 149\4\ scan0393 | |
| Date | 20th August 1937 | |
| SECRET Sg.{Arthur F. Sidgreaves - MD} 126 3 To Rm.{William Robotham - Chief Engineer} from Sg.{Arthur F. Sidgreaves - MD} Copy to Hs.{Lord Ernest Hives - Chair} re Vapour Lock Investigation. Sg{Arthur F. Sidgreaves - MD}12/E20.8.37 On my return I was very much interested to read your Rm.{William Robotham - Chief Engineer}6/AP.16.8.37. It looks as if we had at last got over this trouble but we are of course faced with the fact that we have a large number of cars in existence with the original arrangement. I hope to have an opportunity of discussing this matter when at Derby on Tuesday; also in connection with Wraith. I do not quite understand what is meant in your Rm{William Robotham - Chief Engineer}4/R.9.8.37 because in one part you talk about abandoning the mechanically operated pump and in the other part you talk about the new engine unit having the latest type American mechanically operated pump. I am still as keen as ever to have a mechanically operated pump so that we have an insurance against any failure with the electrical pump. On Page 3 of the former memo you refer to 32-EX with overdrive being inclined to stall on second speed if used for starting and mention that the flywheel inertia is being increased on the Continental P.III to take care of this point, but the Continental P.III has gone into the background and, if I remember rightly, the overdrive is coming in on 'D' Series so I am interested to know whether the flywheel inertia is being increased at the same time. Sg.{Arthur F. Sidgreaves - MD} | ||