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).
Report presenting conclusions and a summary on tests to reduce petrol pump temperature and the effects on carburation.
| Identifier | ExFiles\Box 94\3\ scan0118 | |
| Date | 9th December 1936 | |
| -3- Conclusions. (1) The maximum reduction of average temperature at petrol pump with shutters fixed full open was obtained under touring conditions, and was, approximately, 6.5°C. Under full speed conditions, and dense traffic, the reduction of average petrol pump temperature was only 3°C and 1.5°C respectively. (2) The maximum reduction of average temperature at petrol pump due to deletion of engine side guards was obtained under touring conditions and was 4.5°C. (3) Carburation is slightly impaired at average temperatures in neighbourhood of 0°C, and below by running with by-pass control and shutters full open - this effect, of course, becomes greater as the air temperature falls. Summary. In view of the small reduction of average petrol pump temperature obtained by adopting the by-pass thermostatic control system previously outlined, and also having regard to the cost and complication entailed (since the present shutters would be retained with a modified calorstat), we are of the opinion no useful purpose would be served by going further with the scheme. The likelihood of impaired carburation under severe winter conditions is an additional objection. Further, we understand that the latest petrol pump diaphragms are unaffected by heat, and would emphasise that the above small reduction is an average temperature reduction in cold weather. The under-bonnet temperatures under conditions when failure of the petrol is likely to occur (i.e. very hot weather), will be unaffected by the proposed by-pass control scheme, since the water temperatures under these conditions would be such that the shutters would be full open, or very nearly so, in any case. We are looking into the possibilities of reducing shutter friction etc., so that the temperature at which the shutters are full open is reduced without lowering the average water running temperature. | ||