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).
The investigation into an oil leak from the main bearing on the Wraith engine.
Identifier | ExFiles\Box 115\3\ scan0057 | |
Date | 6th October 1937 | |
File To By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/CTS.{C. Trot Salt - Carburation} c. HS.{Lord Ernest Hives - Chair} c. DS. c. DA.{Bernard Day - Chassis Design} c. HX. WRAITH ENGINE DEVELOPMENT. Feature - Oil leak from the near main bearing into the clutch pit. A considerable amount of work has now been done on the test bed, in connection with the above. The first query which naturally arises is:- What difference is there in design between the Wraith and the present production 25/30 engine, in respect of this oil leak. The difference is larger journals. It should be noted that we do not consider that this oil leak on Wraith is characteristic of the new engine with larger crank, etc., as this oil leak problem has cropped up before. The most important factor, is the speed at which the engine is run. It is our experience that the majority of our engines leak at this point, when run for periods above 3500 R.P.M. It is therefore, difficult to gauge to what extent this leak actually exists on production, as engines are not run for sufficient time at the necessary high speeds to show it. In order that the procedure shall be less confusing the following description of the position to date of an investigation is divided into three groups. (1) Trying to stop the leak, by simple mods. to the existing design of retainers. (2) Trying to prevent the leak, by getting the oil away from the tail (main) bearing before it reaches the retainer. (3) A study of the Vauxhall design of oil retainer and its adoption to Wraith. | ||