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).
Technical memo detailing observations on a universal gearbox fitted to a 7.B.V. model.
| Identifier | ExFiles\Box 99\4\ scan0279 | |
| Date | 24th March 1938 | |
| By.{R.W. Bailey - Chief Engineer} from Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} Da.{Bernard Day - Chassis Design} Hdy.{William Hardy} 428. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls}4/AP.24.3.38 UNIVERSAL GEARBOX FITTED TO 7.B.V. We have noted the following points on this gearbox:- (1) The lever has been shortened to 13½" from shaft centre to the top of the knob. The gear change is light and very crash-proof. Engagement of 2nd. from rest is satisfactory. (2) The synchromesh pins foul the sides of the bronze stirrup causing a clicking noise. This was true of all 3 gears until modified. (3) Overdrive is sufficiently quiet being almost inaudible above 20 m.p.h. It does not work out of mesh down Fenny Bentley. (4) Second speed driving on all teeth jumped out of mesh in a few yards. Driving on 4 teeth only the same coupling still jumps out but after several hundred yards. (5) Oil poured out round the servo due to the wrong hand of oil thread. (6) The oil level rises in the rear compartment. We have now drilled two 3/8 holes through the bottom of the diaphragm to overcome this. (7) There is rattle when pulling at low speeds in direct or over-drive like that on the P.3. overdrive gearbox. Whether this comes from the synchro mechanism requires further investigation. Hdy.{William Hardy} asked for this information in connection with the Phoenix box. Rm{William Robotham - Chief Engineer}/Gry.{Shadwell Grylls} | ||