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).
Clearances and spring modifications for Spectre Self-Adjusting Tappets.
| Identifier | ExFiles\Box 96\2\ scan0007 | |
| Date | 4th July 1934 | |
| x6494 354 To By.{R.W. Bailey - Chief Engineer} c. to RHC.{R. H. Coverley - Production Engineer} c. to E/JNR.{Charles L. Jenner} Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}1/KW.4.7.34. SpectreCodename for Phantom III Self-Adjusting Tappets. With reference to E/JNR.{Charles L. Jenner}6/HP.29.6.34. The clearance we find satisfactory with white metal lined eccentrics is .0025" to .003" diametral. In addition to the other modifications proposed we find that the plunger return springs appear to be excessively strong. Will you please supply weaker springs for trial, one set exerting 25% of existing return load and another set 50%. On the next set of hydraulic tappets built up for the SpectreCodename for Phantom III we should like the plunger clearance to be kept down as low as possible. On the Phantom we have had satisfactory results with a diametral clearance of .00025". Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||