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).
Engagement faults with the Phantom II sequence starter motor and revised test specifications.
| Identifier | ExFiles\Box 61b\3\ scan0234 | |
| Date | 26th March 1931 | |
| X6079 By.{R.W. Bailey - Chief Engineer} from EFC. c. Sft{Mr Swift}/Mr.Brock. EFCl/AD26.3.31. X.6079. PHANTOM II SEQUENCE STARTER MOTOR. As referred to in our EFCl/ADl9.3.31, there have been, as you know, one or two cases recently in which the motors have not properly completed their engagement on chassis test. This has been proved to be due to slight want of easiness in the main sliding bearing and it is understood from Mr.Brock that improvement can be effected in this direction. At the same time we are in agreement that there is little to spare to overcome this slight effect. In order that the motors shall not be passed to chassis which, though having satisfactorily passed our present production test, suffer this fault on chassis test, we have revised the specification of test and attached please find copy of the new specification dated 20.3.31 which please allow to take the place of the old. It will be seen that an alteration has been effected in so far as test (70 and (8) are concerned, this alteration having been designed to prevent the possibility of motors being passed to chassis which will still be unsatisfactory in engagement. A case of uncertain operation occurred recently on a motor on experimental chassis 19-EX, as a result of which we had the motor removed and sent in to us for examination. Regarding this, my assistant's report AD.92 reads as follows :- "This machine ran 25,000 miles without attention and then developed a tendency to fail to engage. On removal it was found to comply with the production test fairly well up to the teazer torque test on which it failed. On the proposed new engaging test it failed on several occasions. It was then dismantled and cleaned. The only defects found were accumulation of oily deposit making all brushes sluggish and the commutator very sticky. The driving end bearing | ||