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).
Proposal sheet regarding an eccentric adjustment for the magneto pinion to address backlash and rattling issues.
| Identifier | ExFiles\Box 81\2\ scan0128 | |
| Date | 22th February 1924 | |
| Oy4-E-22524 February 22, 1924. Mr. Claude Johnson, Rolls-Royce, Ltd., London, England. (Copy for attention of Mr. Royce " " " " Mr. E.{Mr Elliott - Chief Engineer} Platford " " " " Mr. E.{Mr Elliott - Chief Engineer} Hives) Dear Sir: Re: Proposal sheet No.32 Eccentric Adjustment of Magneto Pinion. It was found that in certain cases sufficient backlash developed during running-in of timing gears so that by the time they were quiet they were inclined to rattle at low speeds when the engine impulses were irregular. A slight adjustment of the centre distance between magneto pinion and wheel would overcome this and give perfect gears. For this purpose several magneto bearings were made with bores slightly eccentric. Rather than do this special job in these cases it was thought better to provide an eccentric adjustment as shown on attached prints A-5169 and A-5170. The first eccentric sleeves were made with only .004 eccentricity, but .010 eccentricity is found more desirable, and it is proposed to make the centre distance on the crankcase .005 small so that 3/4 of the available adjustment is inwards. It is thought that irrespective of whether a magneto or a generator is driven from this spindle such an adjustment is desirable and it is therefore proposed to use this form of adjustment on all cars at 1101 on. The oil return from the rear end is arranged for by putting a 45° chamfer 1/8" wide at the rear end of the bore in the crankcase arm, and filing a groove from front to rear along the bottom of the bore. The oil return is as satisfactory we find as on the existing standard parts. Oy. M.{Mr Moon / Mr Moore} Olley | ||