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).
Investigation and revised diagnosis of an oil leak, tracing it from the gearbox case to the speedometer drive.
| Identifier | ExFiles\Box 4\9\ 09-page024 | |
| Date | 13th June 1935 | |
| Hotel de France, Chateauroux, Indre. France. xsgwo GWH.{George W. Hancock - Head Chateauroux}I/Urn.13.6.35. To: "HS{Lord Ernest Hives - Chair}" From: G.W.Hancock. We are entirely wrong in our reports re oil leak from front of gearbox case. We have held the car up in the garage to-day, to try and fathom this job. In the first place, we have been misled by the quantity of oil thrown about at this front end, i.e. clutch and flywheel compartment. We dismantled the gearbox again this morning, and thoroughly cleaned all the faces. Also, we dismantled the starter motor, and found that there is a large cavity in the starter motor housing which was full of oil. How this oil got there we have not been able to come to a conclusion, but evidently this oil has been thrown out with the bumping of the car, and the flywheel has thrown it over the inside of the compartment. After cleaning all this oil up, we ran the engine without the gearbox fitted for two hours, and could not find any trace of oil leak. We then fitted the gearbox unit up, and fitted a pea lamp inside the clutch casing, so that we could observe any leak that may occur. We then ran the engine a further two hours. Everything was very hot, and the oil was in a thin stage, but we were unable to find any trace of oil leak whatsoever. We have, however, found where the leak of oil comes from out of the gearbox. The speedometer drive has underneath a drain hole for allowing small quantities of oil to escape if necessary. We find that this is the point where our big leak of oil occurs. The leak in question is at the rate of 21 drops per minute, and at times is a continual stream. This is the oil that we have been finding in the gearbox undershield. We are to-morrow going to run without the undershield, to avoid any complications, and we hope definitely to prove at the end of the run re any leaks in clutch casing. We shall be pleased if you can give us any data to prevent the oil leak at the speedometer drive. 93 MX{John H Maddocks - Chief Proving Officer} arrived back from Paris this evening. We do not propose to continue the 500 miles per day with this car, but to get purely experimental results from your suggestions. We shall, however, do high speeds, so that we shall be able to forward you oil consumptions. G.W.Hancock. | ||