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).
Brake system issues including servo water ingress, front brake damper stiction, and brake lining wear.
| Identifier | ExFiles\Box 121\1\ scan0211 | |
| Date | 16th February 1940 | |
| Rm{William Robotham - Chief Engineer}/FJH.{Fred J. Hardy - Chief Dev. Engineer}6/ML.16.2.40. (b) Determine whether water enters servo under normal wet road conditions or in a shallow water splash. If it does, experiments to be made with undersheets and/or local shields round the holes to prevent this. As at present made, the servo is intended to be hermetically sealed. It is a little difficult to see why water enters as readily as it does. It is possible that it is sucked in by internal depression created when the servo is warm and is doused by water or snow. This should be determined by measuring pressure in the present servo under conditions mentioned above. All servo levers should be dull nickel plated on 9.B.V. 11.B.V. and all future chassis. The apparent inefficiency of 33.G.V11 servo should be investigated. (4) Front Brake Damper. The front brake dampers, which have been removed from 2.B.50 and 10.B.V. due to "stiction" should be made free and fitted to 9.B.V. and 2.B.50. to see whether the trouble reoccurs. The lever of the damper to be fitted to 9.B.V. should be lightened by making it half the present width. (5) Brake Lining and Drum Wear. In connection with the rapid wear of rear brake linings on 8 cylinder chassis and 12.B.V. the records of lining wear on 8.B.V. during it's 50,000 mile tests and of 9.B.V. should be investigated to see whether their rear linings also wear more rapidly than the front. If this is not so it appears that the trouble is peculiar to hydraulic front brake cars, and may be due to an excessive proportion of rear braking under light braking conditions. - Continued - | ||