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).
Cold weather engine operation, focusing on shutters, thermostats, and the use of alcohol as an anti-freeze.
| Identifier | ExFiles\Box 50\3\ Scan163 | |
| Date | 19th August 1921 | |
| X4305 CC. Mr. Pelnap. Mr. Nadin. OY3/G19.8.21. August 19th. 1921. Mr. Claude Johnson, Managing Director, Rolls-Royce Ltd., London England. Attention Mr. Royce and Works Committee. Dear Sir, Re Part on 4.EX. X.3008. Control of Temperatures. X.4305. X.3764 Replying to R10/G8.6.21 and R8/G12.7.21. With a good design of automatically operated shutter which closes tight and prevents much circulation of air inside the bonnet, we are told that it is not necessary to use alcohol if the driver is careful to cover the whole of the bonnet and radiator with a muff when he stands for more than an hour in very cold weather. It is certainly desirable to avoid the use of alcohol if possible because of the expense involved and the continual trouble which is met with in its use. As pointed out in my letter OY1/G28.1.21, a car fitted with a thermostat cannot be made to retain the alcohol in its circulation system, and the average user of the Cadillac, for example, locks the thermostat open in winter weather so as to promote a better circulation of water in the regulator and so restrain the rapid escape of alcohol. A 30% alcohol mixture by volume will freeze at zero Fahr. and will begin to give off alcohol vapor fairly freely at 140°F.{Mr Friese}, which is far too cool for satisfactory operation of the R-R in winter weather, when it is desirable to keep the water on bonnet may be at a reasonable temperature. Regarding Mr. Royce's remarks on the water heated throttle and carburetter, wethink that the amount of heat at present supplied to the carburetter by the water is only just about sufficient to keep the throttle freezing in winter weather, and cannot be regarded as assisting appreciably towards carburation. If Mr. Royce will examine the gasoline distillation curve sent with my letter OY4/G15.8.21, he will see that a temperature of 175°F.{Mr Friese}, which corresponds about with the water temperature, will only account for evaporating 6% of summer-grade contd:- PAGE 1 OF LETTER DATED 19.8.21 REF. OY3/G19.8.21. | ||