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).
Test results for modifications to anti-judder levers, brake drums, linings, and servo springs.
| Identifier | ExFiles\Box 83\2\ scan0300 | |
| Date | 13th March 1938 | |
| ( 6 ) Parts. Result of Test. Detail Modifications to anti-judder balance levers N.Sch.4865 Rm.{William Robotham - Chief Engineer}350. including spring loaded clevis pins and Etonia bronze bushes for weights. 13,268 miles. The weights did not develop slack in their bearings and the whole system was good for freedom from rattles. This has previously been a serious fault both on 15,000 miles test Bentley and in service. It was necessary at the start of the mileage to reduce the friction in the clevis pins by fitting lighter spring washers. The scheme is recommended for production and for replacements in service as soon as possible to overcome a known trouble. Aluminium Brake Drums on front brakes. O.S. drum failed early in the running. Iron drums fitted for remainder of mileage. MR.3 Brake Linings. Special lining even better for freedom from squeaks than BZ. Proved very satisfactory on Girling rear brakes and superior to BZ used when last Girling axle was run in France. Not satisfactory on Front brakes where subjected to higher temperatures than rear brakes and discarded in favour of BZ which gave no trouble with normal proportion of front braking. No squeaks from MR.3 or BZ with tipping shoes set solid through-out mileage. Pull-on spring on servo link in place of star springs to prevent servo judders. 15,020 miles. Thoroughly satisfactory and gave no trouble at all. Deletion of star springs noticeably reduces lost movement in brake pedal. | ||