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).
9,000-mile report on vehicle 19-EX, detailing engine, fuel pump, ignition, and piston performance.
| Identifier | ExFiles\Box 11\4\ 04-page142 | |
| Date | 23th July 1932 | |
| To Hs.{Lord Ernest Hives - Chair} From G.W.H. Hotel de France, Chateauroux, FRANCE. 23.7.32. REPORT ON 19-EX. AT 9,000 MILES. ENGINE. The engine has run very smoothly generally. The half crankshaft period has been eliminated by fitting cotton duck discs to the Low Inertia Damper. They do away with the initial stickiness which is the chief cause of the trouble, by never getting to the state of a glass surface. The load remains more consistent than when using other material. The spreading and jamming of the discs, which previously caused trouble, has been overcome. We have of late, been forced to the conclusion that engine oil causes a large percentage of Damper failures. The engine oil during hot weather, or if not changed, becomes very gummy. The gumminess or varnish is transmitted to the discs of the damper which alters the characteristic of the slipping load. This becomes worse as time goes on and is, we believe, the cause of so many service failures. We noticed this condition particularly when we first dismantled the low inertia drive. We therefore changed the oil using Shell Aero in place of Wakefields XL, but during the time with the Rabestos discs in the damper, we were unable to detect any difference. The engine gear rattles have been considerably reduced also by the smoother working of the Damper. PETROL PUMP. We have had no repetition of the failure of the petrol supply or the flooding of the carburetter. The failure of the petrol supply we can, with every assurance, say was due to the pump failing to draw petrol through a partially choked Enots filter, and that with an Autovac the partially choked filter would not have caused a failure. IGNITION PLUGS. There has been no repetition of plugs misfiring during the remaining portion of the mileage. PISTONS. With the exception of No.5 cylinder overoiling | ||