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 and ongoing experiments on gears, servo, propeller shaft, rear axle, and braking systems.
| Identifier | ExFiles\Box 98\4\ scan0035 | |
| Date | 21th December 1938 | |
| -2- Rm{William Robotham - Chief Engineer}/IMW.{Ivan M. Waller - Head of Chateauroux}15/JH.21.12.38. except that occasionally second gear failed entirely to synchronise. All gears are noisy and would not pass on production. Experiments with softer rubber in various positions to replace the rear mounting are in progress. The scissor load to apply the servo is 18 lbs. This should be 12 - 14 lbs. This is due to discrepancy in the preload on the new diaphragm spring which is receiving investigation. The previous spring on 8.B.V. functioned correctly. A foul occurred between the shank of the eye on the front brake rod and the distance piece at the front of the bracket carrying the servo plate levers. This has been pointed out to the design department and required modification. While the alteration is being carried out we recommend that the centres of the inner and outer plate levers be spread in order to reduce the possibility of fouls between them due to distortion or variation in limits. It is agreed that they are too close and fouls have already occurred. Propellor shaft. The rear shaft with 25° angularity for the rear joint ex 8.B.V. has been fitted. Half nuts and grover washers have been fitted to all the flange bolts, and the rear ones have been reversed to give the required angularity without fouling. Rear Axle. This is the semi floater with 45 m.m. shafts. We have called for 40 m.m. shafts in S.A.E. 4140 and when these are ready the latest oil seals and modifications to prevent oil reaching the rear brakes will be required. The N.S.R. wheel nuts worked loose on the road. Left hand threads for this side of the car have been called for. Brakes. These are lined experimentally with TSM/B. The rear brake have been re-rated to prevent them locking at low pedal pressures by modifying the rear equaliser so that the input lever and the T lever are of equal lengths. This arrangement is also running on 8.B.V. A full analysis of the efficiency of the various components of the system is in progress in order to discover the cause of the lack of front braking as experienced on 8.B.V. The hand brake was stiff to operate owing to the GW.394 plate rubbing hard against the ratchet gradrant. This has been brought to the attention of the design dept. | ||