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).
Tests to overcome an oil leak from the Shock Damper Governor unit.
| Identifier | ExFiles\Box 151\2\ scan0263 | |
| Date | 27th July 1934 | |
| +4698 To Ey. c. to R. {Sir Henry Royce} c. to Hsy. c. to Mr. c. to S.B. c. to WOP. Shock Damper Governor Unit Oil Leak. We have been carrying out a number of tests to overcome an oil leak which comes from the drain hole on the flanged joint where the governor unit attaches to the change speed mechanism. This oil leak is proportional to the height of the oil in the governor unit. That is, if the unit is filled to the present intended level, which is at the bottom of the filler spout, the leak is negligible. However by removing the top cover of the unit it can be filled to the top of the filler spout, and in this condition the excess oil leaks out of the drain hole. Our experience shows that this leak is not serious, although objection is liable to arise concerning the messiness of the unit, if the unit is filled to the top level. We have been carrying out tests to overcome this leak so that we can fill the unit to the high level, and thus have a larger capacity of oil in circulation in case of a leak from one of the olive joints in the pipe line system to the dampers. The cause of the leak is due to the fluctuations in pressure inside the unit, owing to the displacement of the pump. Therefore the larger bore pump on the 25 HP. is worse than the Ph.II. We have run 10,000 miles with a 25 HP. governor unit without having to replenish with oil. By venting the unit we have been able to overcome the leak and allow the high oil level to be used. In order to find a suitable place for venting the unit, without making an alteration to the unit casting, we have had to change the direction of the oil release orifice by 90°. This has enabled us to vent the top cover. Before the position of the oil release orifice was changed, any vent in the top cover leaked oil and became blocked with an oil film. | ||