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).
Discussion about one-stage and three-stage relief valves and their effect on oiling for 20 HP and Phantom engines.
| Identifier | ExFiles\Box 106\5\ scan0038 | |
| Date | 29th October 1928 guessed | |
| contd :- -2- that car is that we only have a one-stage relief valve. The feed to the rockers is simply the over-flow oil and is under no definite pressure. The new type relief valve which was made for the w 20 HP. also had only one-stage. We have previously had this difficulty and asked that the 20 HP. should have a similar relief valve to the Phantom, in fact, 9G3 is running with a Phantom relief valve. We are not using on either cars any oiling scheme which operates with the rocker movement. On the Phantom we have a groove so that on the push rod side we get a continuous stream of oil. We find that this does help in reducing wear and noise from the tappets. We cannot however have the same amount of oil going to the valve guides otherwise we are in trouble with the oil getting passed the valve stems and causing the engine to smoke. We therefore consider that an urgent requirement on the 20 HP. is a 3-stage relief valve similar to the Phantom. Hs.{Lord Ernest Hives - Chair} | ||