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).
25/30 HP complaint regarding carburetter and plug trouble with the use of ethyl fuel.
| Identifier | ExFiles\Box 162\3\ img026 | |
| Date | 23th October 1936 | |
| To Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} Cricklewood. 23.10.36. 25/30 H.P. Complaint Carburetter V Plugs. We have obtained further information with regard to plug trouble with the use of Ethyl, which follows very closely the symptions that we are experiencing on the 30 HP. The information has been obtained from Mr. Ervine of Champion Plug Co. (1) Hot plugs are more prone to collect Lead deposit then cool plugs. (2) Lead deposit forms more quickly with low speeds. (3) High speeds (as with Bentley or touring conditions) there is less chance of the deposit forming. (4) Mica insulation is more prone to collect fine particals of the lead than china insulators. (5) Glazed china insulators attracts lead deposit. (6) Unglazed china or matt finished is less inclined to the deposit formation. (7) Preignition of plugs is known to occur at speeds which one would not think possible due to the fine particals of lead becoming incondesent. (8) A slightly weak mixture in the range of carburation would be sufficient to develop the No.7 paragraph. (9) The Champion plug people claim that their unglazed porcelain plugs are definitely less prone to troubles with the use of Ethyl than any other plug. | ||