Letter from Champion Spark Plug Co. discussing ignition system troubles and spark plug performance.
| Identifier | ExFiles\Box 162\3\ img193 | |
| Date | 15th April 1940 | |
| elect File 6000 C O P Y FROM : CHAMPION. TOLEDO. TO : CHAMPION. FELTHAM. (Mr. R.A. Lydy). DATE : 15th APRIL 1940. Dear Bob, re: Your letter MD-105, March 15, 1940, missing troubles at Rolls Royce - reported by Mr. Irving. Undoubtedly this is a case of the standard ignition system not having sufficient reserve output, especially to ignite gas of lower volatility than normally used. Naturally, the surface of all electrodes becomes slightly oxidized or coated, and gaps possibly slightly widened, even at 2000 miles, and should logically have greater resistance. It is possible that removing the plugs and rubbing a gap gauge between the arcing surfaces would help just enough to show improvement in firing. Also, it is likely that during removal of the allegedly offending plugs, appreciable drying and evaporation of wet fuel deposits took place, especially on the surface of the insulator. This would assist in removing another contributing cause of missing. We have had parallel cases here, in which at 2000 to 5000 miles missing could be cured by new plugs, regapping old plugs, new or cleaned breaker points, or new coil, or other distributor parts. In every case, our spark plugs were absolved from blame, as improved ignition systems enabled plugs to give 10,000 miles or more, even with wide gaps. Obviously, the remedy at Rolls Royce is the use of a suitable ignition system having greater output for a safety factor. With best regards, we are, Very truly yours, Signed. E. {Mr Elliott - Chief Engineer} S. TWINING. Engineering Department. | ||
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).