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).
Consistent valve clicking noise found in Phantom engines fitted with double valve springs.
| Identifier | WestWitteringFiles\S\March1928-May1928\ Scan181 | |
| Date | 11th May 1922 | |
| To. [Struck through text] ✓ C. to [Struck through text] ✓ C. [Struck through text] ✓ C. to DY.{F R Danby} ✓ ORIGINAL Hs{Lord Ernest Hives - Chair}4/LG11.5.22. x290 ----- x8060 ----- x7060 PHANTOM - VALVE SPRINGS. The first engines being produced with the turbulent head are instructed with standard single type valve springs. We have had comparatively very little trouble with these springs. The valve clicking noise has been consistent on 5 or 6 engines to which the double springs have been fitted. Hs.{Lord Ernest Hives - Chair} | ||