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).
Letter from H.M. Hobson, Ltd. discussing gauge installation, pump performance, and petrol vaporization.
| Identifier | ExFiles\Box 44\4\ Scan031 | |
| Date | 4th April 1929 | |
| Messrs. Rolls-Royce, Ltd., Date 4.4.29. Page 2 In connection with this installation, we recently coupled up a gauge on one of your new chassis at a coach- builders, and we noticed that in this instance the air line had been led very close to the exhaust pipe. We think it would be advisable to keep this as far as is practicable from the exhaust pipe, on the lines agreed between us on one of the writer's visits to your works. We note with interest the results which you have obtained when running a comparison between the two units on the same car in France, and we should like to know to what the over-night losses experienced on the unit without the pump amounted. We note that the pump proved its value under these conditions, and we are glad to learn that its incorporation is thus fully warranted. We conclude that the petrol used was ordinary "Tourisme", which we believe approximately corresponds to our No.1 in this country, although vapour pressures for petrols apparently vary at different times of the year, which must have a bearing on the amount of vaporization taking place in the tank. Yours faithfully, H.M. HOBSON, Ltd., F.P. Searight Joint Managing Director. | ||