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).
Oil relay ignition control failure and the recommended alternative ignition system.
| Identifier | ExFiles\Box 65\1\ scan0030 | |
| Date | 25th September 1924 | |
| R.R. 493A (50H) (D.B. 175 25-9-24) J.H.D. V8685 EXPERIMENTAL REPORT. Expl. No. REF: Hs{Lord Ernest Hives - Chair}/1/1093.12.24. To R.{Sir Henry Royce} from Hs.{Lord Ernest Hives - Chair} c. to CJ. BJ. c. to E.{Mr Elliott - Chief Engineer} DA.{Bernard Day - Chassis Design} c. to EY. Wor.{Arthur Wormald - General Works Manager} SECRET. X8770 X8685 EAC, 'V' SERIES. We have just run the first EAC, engine on the road fitted with the Oil Relay Ignition Control. After a short run the oil relay ceased to function. The cause was found to be due to dirt on the piston valve. The valve fitted had an increased clearance over the original clearance of .002". Further tests have been carried out on the bench and we find that we can have .005" on the valve without any serious loss of oil, even when very hot. It is disturbing to think that the efficiency of both ignitions can be destroyed if a particle of dirt happens to cause the valve to stick. When it does stick, it sometimes means that the whole unit has to be taken to pieces to free it. X8790 V4187 We recommend that we prepare, so that we can, if necessary, fit the governed Scintilla Magneto and the standard battery ignition on 'V' series. This arrangement does work quite satisfactorily and was fitted to 93-NK car which was approved by Sales. It has the advantage that we retain two completely independent ignitions. The Scintilla magneto is considerably more silent than the Watford. Hs.{Lord Ernest Hives - Chair} | ||