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).
Design of an electrical oil level indicator for the Bentley 50, proposing an alternative arrangement.
| Identifier | ExFiles\Box 111\2\ scan0294 | |
| Date | 31th January 1938 | |
| To Da.{Bernard Day - Chassis Design} c. to Jnr.{Charles L. Jenner} 851 1044 Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems}1/JH.31.1.38. 800. ELECTRICAL OIL LEVEL INDICATOR ON BENTLEY 50. The drawing showing the proposed position of the oil level indicator as supplied by Messrs. S. Smith & Sons, allows for a variation in oil level of 3". We pointed out to them that we would have nothing like this variation in level and asked what was the shortest arm on to the float that it would be possible to use. They inform us that it would not be advisable to use an arm of less than 2" on account of sticking. An arm this length would only give approximately 45° movement on the instrument with the variation in level that we are likely to have, whereas the instrument requires a range of 70° to cover the scale on the meter. In view of these difficulties we suggest that if the instrument is still called for the simplest way to arrange it would be to use a similar lay out as has been suggested for the Wraith where the needle and scale have been moved up to the top half of the crank case. The Smith's instrument could then form the pivot for the needle. This would have two advantages (1) There would be no cork joint on to the sump (2) There would be a direct reading of the oil level where it is required when filling up. This arrangement would require a fairly large float and it is just possible that floating intake might be made larger to work the indicator. Rm{William Robotham - Chief Engineer}/JBD.{John B. Dixon - Fuel Systems} | ||