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 of CM5H brushes in sequence starter motors.
| Identifier | ExFiles\Box 61b\3\ scan0215 | |
| Date | 12th January 1931 | |
| RR 23B (150 BKS.) (DB{Donald Bastow - Suspensions} 451-8-12-24) MP 306975 X6050 ROLLS-ROYCE LTD. INSTRUCTIONS. To EFC Order No. AD. 81 Customer's No. X 6050 CM5H Brushes on Sequence Starter Motors Motor X was fitted with these brushes in May 1929. It ran 4000 miles on 18 Ex and was then removed, cleaned, examined, tested and reported AD44 19-11-29. mX.{John H Maddocks - Chief Proving Officer}7625. B It then ran 8000 miles on 27Ex was removed for fitting sharp-edged pinion and refitted, running a further 4000 miles to date, a total of about 16000. The motor is still working satisfactorily on this car. Motor Y was also fitted with CM5H brushes and ran 6500 miles on 22EX. It then failed owing to ingress of water causing the holders to corrode and the brushes to seize thus spoiling the test although the brushes themselves (overd) Signed This Sheet must be filed on completion of the work. | ||