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).
Design improvements for breather pipes, rocker cover nuts, petrol systems, and thermometer pipes.
| Identifier | ExFiles\Box 30\1\ Scan050 | |
| Date | 21th September 1934 guessed | |
| - 6 - Length of Breather Pipe from Rocker Cover to air silencer. --------------------------------------------------------- With regard to the complaint that this could not be removed on 21-G-IV, Design Department are investigating the dimensions of the details to ascertain why this has come about. Valve Rocker Cover Retaining Nuts. ---------------------------------- It was agreed that these nuts should be fitted with a spring ring or other means of retaining them to the cover. On both the P.2. and Bentley the rockercover holding down nuts remain with the rocker cover after they have been released from their studs. The 20-HP. car should be brought in line with these. Petrol System. -------------- GWH.{George W. Hancock - Head Chateauroux} reported very favourably on the all metal type of flexible petrol pipe which was fitted to one of the cars tested in France. Actually 21-G-IV was not fitted with a flexible type of petrol feed pipe but with a copper pipe with a coil in it. For production the metallic type of flexible pipe should be used. With reference to the two failures which occurred of the autovac suction pipe, a design has been issued to overcome this. Some further discussion ensued re petrol systems at the conclusion of which it was agreed that on the next 20/25 HP. car for test in France we should discontinue to use the autovac. The great disadvantage of the autovac is that it upsets the good slow running of the engine which we have obtained with the new type carburetter. Now that the reliability of the S.U. electric pump is established it would appear better to use this on the 20/25 HP. car in conjunction with the type of petrol tap as instructed for SpectreCodename for Phantom III. This will affect a considerable saving in the length of petrol piping used. Thermometer Pipe Failure. ------------------------- Design department agreed to issue instructions with regard to the coiling the thermometer pipe in order to overcome the failure which occurred in France. At the same time the oil gauge pipe will receive similar attention. | ||