The testing of a 20 HP oil relief valve which is chattering and vibrating.
| Identifier | ExFiles\Box 66a\4\ scan0025 | |
| Date | 30th November 1926 | |
| To R. {Sir Henry Royce} from Hs {Lord Ernest Hives - Chair} /AJL. c. to RG. {Mr Rowledge} BJ. c. to Wor. {Arthur Wormald - General Works Manager} E. {Mr Elliott - Chief Engineer} c. to DA. {Bernard Day - Chassis Design} BY. {R.W. Bailey - Chief Engineer} c. to OY. X8205 Hs {Lord Ernest Hives - Chair} /AJL1/LG30.11.26. 20 HP: OIL RELIEF VALVE (LeC|2235). X5205 This scheme embodies a bow spring type relief valve in one unit with the existing oil pump. This type of valve has been used successfully on the Phantom. When fitted to the 20 HP. pump as per the scheme LeC.2235, the relief valve chatters and vibrates very badly when the oil has become hot. The noise is not just a slight chatter but builds up to very big dimensions eclipsing by far all other engine noises. Various strengths and ratings of valve springs have been tried but make no improvement; variation in the size of the aperture through the valve makes no difference and a Phantom bow spring and valve fitted in the same position as the 20 HP: valve chatters equally as badly. A Phantom relief valve unit was tried in conjunction with the pump, its own valve having been removed, the Phantom relief valve unit was carried on the engine near the battery ignition distributor, the relief valve intake union being connected to the pump at the low pressure delivery union. Connected up in this matter the Phantom relief valve chattered badly (only the high pressure valve was used in this test). The medium pressure valve was then added to the relief valve unit and the chattering decreased slightly. the addition of the third and low pressure valve made no further improvement. contd :- | ||
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).