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).
Vehicle performance issues and B.V. engine development experiments.
| Identifier | ExFiles\Box 161a\3\ scan0008 | |
| Date | 6th January 1939 | |
| -7- (6) CHANGE SPEED - STICKNESS IN GEAR SELECTION. This is mainly due to the need for flexibility in the change gear operating shaft due to soft engine mounting. It is somewhat increased if dirt enters the bushes and a rubber cover is being incorporated to protect the bearing end. (7) PROPELLER SHAFT VIBRATION. This will be corrected by axle inclination to suit the correct Hypoid, as has been done in the Wraith and 1.B.50 satisfactorily. (8) STEERING JOGGLES. This complaint was a slight oscillation of the steering wheel on even normal road surfaces. It is suggested that the damper poundage was too low owing possibly to changes in running conditions, and this is one of the points which Rm{William Robotham - Chief Engineer}/AFM.{Anthony F. Martindale} will investigate when he takes over for his portion of the test. (9) AXLE NOISE. The bevel gears in this axle are experimental, as we now find that the original Bentley gears fit the conditions satisfactorily, both on the dynamometer and the road, and there is no intention to go to this increased Hypoid for which this axle was originally designed. ENGINE DEVELOPMENT. B.V. ENGINE TEST BED WORK. The following are the major experiments in hand on the B.V. engine:- Endurance running on raised crown pistons. Main bearings without shims. Vandervell thin shell bearings. .4 carbon crankshafts. Less costly components which include, thin shell rocker bushes, cast iron camshafts, .4 carbon steel push rods, motor component valves. Investigation work has been carried out on the valve spring breakage which took place in France, and a test will be run on double valve springs. The suggestion is that since we have deleted the tappet spring which we used to have on 'M' series engines, a greater load is placed on the valve spring and that this causes the failure. [handwritten] previous page | ||