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 performance and issues with a semi-floating rear axle and Girling type brakes.
| Identifier | ExFiles\Box 97\4\ scan0177 | |
| Date | 23th November 1938 | |
| -6- Rear Axle. Semi-floating axle No. S.E.V. 9 x 37 ratio. The axle gears remained quiet. The only trouble experienced was oil leaks past the oil seals in the hubs, which found their way on to the brakes. This is receiving attention. Brakes. Girling type. Front and rear drums and shoes interchangeable. Cast iron drums and BZ linings. Servo lined with RAD.13. Long arm rear brake equaliser LOP.GB.3902. SCD.580. PD.215. Hydraulic damper as front brake dashpot SCD.698. UW.1394 metal stop on hand brake in place of rubber stop. UW.1990 Hand brake pull off spring. Hand brake travel increased by increasing length of ratchet from 9 teeth to 11 teeth. The general characteristics of the brakes were good and they remained more constant in output and more reliable than any previous Bentley brakes. Light squeaks were experienced from brakes and servo early in the running. These became no worse but occurred at intervals, particularly when cold, throughout the mileage. Linings which are hoped to cure this are now being fitted for further test. While the retardation was satisfactory under normal conditions, it was found that with heavy application such as would be used in an emergency, there was insufficient front braking to give a good stopping distance and the rear wheels locked with a relatively light pedal pressure. The output of the rear brakes varied further due to oil which escaped from the axle. These points are receiving investigation and modifications are being made. The wear of the front brakes was negligible. The O.S.R. wore to the rivets in 8,476 miles. It was relined and again wore to the rivets in 7,255 miles. The N.S.R. wore to the rivets in 15,002 miles. The new linings fitted covered 729 miles up to the end of the running. They were in bad condition, due to oil and overheating. Grease retaining caps on the Girling expander housings are required. | ||