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).
Engine component failures, oil and petrol consumption analysis.
| Identifier | ExFiles\Box 108\3\ scan0227 | |
| Date | 9th March 1932 | |
| -2- pushing lightly on the clutch pedal. The Fabroil camwheel wore badly causing engine gear rattle. Lister's material with improved wearing qualities has been instructed for production. Several taper pins securing the distributor driving cog broke, also the governors of both Delco and B.M. distributors. A spring drive will be incorporated for production as used in America. Tappets lost clearance due to sinkage of the exhaust valve seats. This coincided with the failure of a distributor driving pin which caused late ignition and bad overheating of the engine. Both before and after this the tappet clearances remained reasonably constant, although further sinkage was noted when finally stripped. Practically all the troubles experienced with this unit can be attributed to vibration at high engine speeds. The oil pressure was maintained throughout, and never fell below 30 lbs/sq.in. at 70 m.p.h. The highest oil temperature recorded was 128°F.{Mr Friese} The running temperature was between that of the present 25/30 and Bentley. The oil used was Vacuum Mobiloil A.{Mr Adams} The consumption during the first 2,450 miles running in France was 740 m.p.g. This represented a total mileage for the engine of 5,850 miles. During the next 1,000 miles it improved, and from then onwards varied between 1100 and 1790 m.p.g. according to how hard the car was driven. The average consumption for the French mileage was 1350 m.p.g. Oil leaked from the rocker cover joint. Experiments are being carried out with a scheme to prevent this. Less than a pint of oil was collected from the clutch pit drains during the entire mileage. The average petrol consumption was 11.1 m.p.g. at Chateauroux and 13 m.p.g. during the run by MX.{John H Maddocks - Chief Proving Officer} | ||