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).
Faults found with a clutch during a 4,000-mile test run in London.
| Identifier | ExFiles\Box 130\2\ scan0358 | |
| Date | 16th December 1936 | |
| 1113 E.{Mr Elliott - Chief Engineer} from Rm{William Robotham - Chief Engineer}/GWH.{George W. Hancock - Head Chateauroux} c. to Hs.{Lord Ernest Hives - Chair} c. to By.{R.W. Bailey - Chief Engineer} c. to Mx.{John H Maddocks - Chief Proving Officer} Rm{William Robotham - Chief Engineer}/GWH{George W. Hancock - Head Chateauroux}1/R.16.12.36. Report on Clutch during 4,000 miles running in London 16.10.36. to 7.12.36. The clutch to begin with was smoother than the average clutch on owner's Phantom III's, but in common with these the engagement takes place over too small a range of the total pedal travel. This gives rise to fierceness unless the driver's whole attention is concentrated on the operation of the clutch. The following faults were noted:- (1) Jaggers when hot. These could be avoided with very careful manipulation on the level but were inevitable getting away on an incline. There was a noticeable improvement after 2000 miles running; jaggers were then very slight except when very hot, up to 3500 miles, after which they became worse than those experienced before. The clutch was smooth in engagement when cold throughout the mileage. (2) Squeaks in engagement. These were reported as occurring on every engagement during the first 200 miles running after leaving Derby, and continued to occur at less frequent intervals up to 2000 miles, after which no further squeaks were heard. During the traffic running they happened at odd times, often when not expected, and were not easily reproduced. (3) High pedal pressure. This was most objectionable for prolonged driving, and fatigued the leg and ankle muscles enough to considerably reduce the smoothness with which the pedal could be let up. (4) Spinning. The clutch did not free readily when hot, and at times started again after stopping. When cold the drag of the cold oil in the gearbox was sufficient to stop the engine spinning. There was an improvement when the pedal travel decreased, but it was always bad enough to make the engagement of reverse liable to be noisy. The spinning is attributed to general mis-alignment setting up high loads in the various bearing and frictional surfaces. | ||