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).
Letter to Rolls-Royce of America discussing starter motor troubles on American chassis, specifically lubrication and switch issues.
| Identifier | ExFiles\Box 62\1\ scan0017 | |
| Date | 11th February 1932 | |
| X6079 Hs{Lord Ernest Hives - Chair}/Wst.4/AD. February 11th, 1932. Mr. Soutter, Rolls-Royce of America Inc. Springfield, Mass. Dear Sir, P.II. Starter Motor Troubles on American chassis Mr. Robotham has informed us that you are experiencing trouble with starter motors. From his report it appears to us that the majority of the complaints have been due to sluggish longitudinal motion of the motor armature. We do not think that this has been due to dirty commutator alone but due to the excessive lubrication of the bearings. We have found that when these bearings become excessively lubricated the oil tends to congeal in extremely cold weather and present sufficient friction to prevent engagement. We have made tests on the grade of brushes of this motor and we do not think that these can be improved upon. We are experimenting with our starter motors in order to improve the bearings from this point of view. Another point which has cropped up and which has necessitated modification, is that the small trigger switch operated by the motor armature does not operate soon enough in the stroke of the motor. On the early motors the armature had to go practically into full engagement before the trigger switch, which is in circuit with the main relay switch, operated. A modification has been issued for these levers so that the trigger switch operates very early in the stroke just after the pinion has engaged with the flywheel. We have found this to be a very definite improvement and has cured a number of troubles and complaints due to incomplete starter operation. | ||