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 investigation and testing of faulty front brake linings.
| Identifier | ExFiles\Box 140\4\ scan0186 | |
| Date | 23th February 1938 | |
| -2- 23rd. February 1938. We removed the drums and with instruments carefully measured the pull in the front brake actuating mechanism, on both sides of the car simultaneously. We were unable to detect the slightest difference in pull on either side. Nevertheless one brake had worn about six times the rate of the other and was coated with black powder. We had taken the greatest care not to over-heat even this brake during the running on the road. We observed that the drums were fouled in patches on the rubbing surface with a tacky substance. We cleaned the drums and re-assembled, with the linings changed from one front brake to the other. We could not, as previously, transfer only one shoe of one side to the other, owing to the dissimilar linings, the shoes being handed. The car immediately began diving to the opposite side of the road, proving conclusively that the linings are at fault. 400.M appears to have as its binding medium an unstable and unduly soft substance which is erratic in its behaviour and sticks to the drums in patches, producing an unpleasant rumbling when braking. We have no further interest in it. The "D" is more satisfactory and the front brakes of this car are now lined with it. We will report further on its behaviour in due course. Yours faithfully, for ROLLS-ROYCE LTD. | ||