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).
Various mechanical issues including speedometer cables, clutches, and gearboxes.
| Identifier | ExFiles\Box 135\2\ scan0210 | |
| Date | 14th August 1940 | |
| -5- Rm{William Robotham - Chief Engineer}/Wym.{G. Harold Whyman - Experimental Manager}1/SW.14.8.40. Production B.V. pipes have a diameter of 3/8" and on the rationalized cars the dia. is 1/2". Speedometer & Rev. Counter Drive Cables. On all our cars at some time or another, these have given trouble, they either become noisy or cause the instrument needle to "flutter". Special cables tried up to now have not been any improvement. The only known cable which is satisfactory is the old type thick one. This is at present fitted to 11-B-V.{VIENNA} One contributing factor is that on most cars the hole in the dashboard through which the cable passes is not in alignment with the instrument itself, and consequently should be kept in mind by Design when finalizing the instrument layout. The speedo trip instrument on 8-B-V failed. This was returned to the makers for their examination and comments. They found that the trip mechanism had been badly strained, causing the ratchet driving plate to be forced off the pins. CLUTCHES. Clutches generally are behaving satisfactorily although slight jaggers have developed on 9-B-V and 1-R-1. This will be investigated as soon as time allows. Clutch trunnion races have failed on 10-B-V and B.22.AW. The scheme fitted to 10-B-V is obsolete and can therefore be disregarded. On B.22.AW, the race failed after 7,000 miles the lubrication was adequate, but we have since found that on the centrifugal type of clutch fitted to B.V. and B.60 engines, some distortion of the clutch finger takes place at high engine revs, causing the clutch pedal to lift 1/4". This has caused the pedal to come up hard on to the floor-board and thus put a terrific load on the trunnion race. We consider this may be the cause of the failure of the race and investigations are being carried out at the moment by Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer} GEARBOXES. Gearboxes at the moment are one of the high spots of our cars requiring further attention. The main troubles are synchrocone rattles, particularly in over-drive, but also in evidence in direct gear and failure to synchro-mesh. B.22.AW is a bad example of over-drive rattle, and 11-B-V and 1-R-1 cars are poor for synchro-mesh. A number of new gearboxes were due to built some months ago, but these have not yet materialized. | ||