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).
The unsatisfactory performance of a car's clutch and throttle, detailing issues like jagging, transmission slackness, and a sticking throttle.
| Identifier | ExFiles\Box 96\3\ scan0094 | |
| Date | 3rd June 1936 | |
| S/W. Rm.{William Robotham - Chief Engineer} C. to Sg{Arthur F. Sidgreaves - MD} C. " " F.{Mr Friese} C. " " Mx.{John H Maddocks - Chief Proving Officer} Swdd. (crossed out) LESmeth (crossed out) X360 re - 34-EX. Cx{Major Len W. Cox - Advertising Manager}14/KW3.6.36. Further use of this car shows that the clutch is remaining in an unsatisfactory condition and jagging at times a good deal. We hoped that with use it might settle down to behaving itself and with that object I used it over Whitsun, in order to decide whether after Whitsun it was fit to send on Press demonstration runs and to use for ordinary trial run work. At times I was very optimistic about the clutch, but this optimism was not justified for at moments it was just as bad as ever. You will have heard that I telephoned this morning to Mx{John H Maddocks - Chief Proving Officer} to get his views on using dope temporarily, and whoever I spoke to agree that as the clutch is standard and you have nothing else to offer us there would be no harm in trying that temporarily at least. A point that may be contributing to the jagging of this clutch has revealed itself in a very noticeable slackness somewhere in the transmission, which is particularly in evidence on 2nd and 3rd speeds. This may be a perfectly normal condition, as I know it has been prevalent in P.III's of the experimental type. There is, however, a definite 'clonk' which could be heard and felt when one accelerates and decelerates on second gear, but how much that contributes - if at all - to the clutch behaviour I, of course, cannot say. Another unpleasant feature asserted itself and that is the throttle stuck fully open after a stretch of road at high speed, but fortunately released itself with some violent depressing of the accelerator pedal. This throttle appears to be suffering from peculiar characteristics apart from this point, or it may be some other portion of the carburetter, but when the car is overrunning the engine with the throttle not dead shut but just sufficiently closed for the engine not to be pulling, an effect is produced without moving anything, of the engine suddenly luffing up, or almost giving the impression that someone has applied the brakes slightly. I noticed this several times, but whether it is possible for the throttle or any parts in the carburation scheme to move without a corresponding movement of the accelerator pedal, I am not sure. Possibly this brief description of these peculiarities may help you to trace the cause. Cx.{Major Len W. Cox - Advertising Manager} Rueb | ||