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).
Pros and cons of Discol fuel compared to Ethyl fuel, leading to a recommendation for its use.
| Identifier | ExFiles\Box 150\1\ scan0314 | |
| Date | 30th March 1938 | |
| By. {R.W. Bailey - Chief Engineer} from Rm. {William Robotham - Chief Engineer} c. Sg. {Arthur F. Sidgreaves - MD} c. Hs. {Lord Ernest Hives - Chair} c. MX. {John H Maddocks - Chief Proving Officer} c. Hd. {Mr Hayward / Mr Huddy} c. W/K. c. W/LH {Mr Haworth} - JLE. {J. Lee Evans - Chassis Test Manager} 1235 (handwritten, crossed out) 1282 (handwritten) DISCOL FUEL. Rm {William Robotham - Chief Engineer} 7/M.30.3.38. Recently a number of cases have been brought to our notice where customers have been highly satisfied running on Discol fuel. Perhaps the most noticeable example was a Gentleman from Lincolnshire who had run 55,000 miles on Discol without decarbonising. We tried his car and it seemed to be in excellent condition. Another point in favour of Discol is that it is free from plug trouble which has been a great source of annoyance with Ethyl fuel. From a service point of view, however, we believe that the latest sparking plugs have largely overcome the miss-firing at low speeds on Ethyl. The only definite disadvantage of Discol that we have experienced experimentally is that it does cause deterioration of the present petrol pump diaphragms. In customers hands, however, this trouble does not seem to occur at less than 25,000 miles. We have now petrol pump diaphragms on test which are entirely immune from the effects of Discol. The attached report shows that Discol is actually better for detonation than Ethyl, also, that while special carburetter needles are, theoretically, desirable, in practice very little disadvantage occurs through running with the normal carburetter setting. The Americans have told us that cylinder bore wear is likely to be worse with alcohol fuels, but so far we have no evidence of this. It is certain that Ethyl causes us to spend quite a lot of money stelliting exhaust valves. In view of the foregoing, we believe that the time has now arrived when we can, with advantage, recommend Discol in our Instruction Books as an alternative to Ethyl, and if service reports are favourable at the end of 12 months, or so, there would seem to be a certain amount of justification for recommending it in preference to Ethyl. Rm. {William Robotham - Chief Engineer} | ||