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).
Notes on engine stalling, gear lever vibration, oil leaks, and testing of high-pressure petrol pump configurations.
| Identifier | ExFiles\Box 91\2\ scan0353 | |
| Date | 18th September 1937 | |
| 6. RM{William Robotham - Chief Engineer}/TML.1/MP.18.9.37. It was noted that the tendency for the engine to stall on get-away with low revs which is a feature of the Phantom III engine was somewhat accentuated by the higher second gear. Experiments with a heavier flywheel are in progress to overcome this trouble. The vibration on the gear lever above 60 m.p.h. was noticeable when changing gear above this speed. With the standard gear box there is no need to touch the lever above 50 m.p.h., so the trouble is less noticeable. Oil leaks occurred from the front bearing. S.U. High Pressure petrol pump on frame. This was run the full mileage in conjunction with various auxiliary schemes and pipe arrangements. One side was fitted with experimental steel rollers which were not altogether satisfactory. The other side with standard brass rollers gave no trouble and the pump was in excellent condition at the end of the running. It was noted that under all ordinary conditions, the delivery of either half of the pump working by itself was sufficient to give maximum speed. The standard pump on the dash under the bonnet and a single unit high pressure pump on the side strip under the bonnet were each tried in turn, piped up in parallel with the frame pump. No merit could be found for the arrangement with the standard pump in parallel and it necessitated mounting the various pipes in positions exposed to the maximum under bonnet heat with consequent vapour troubles. The single high pressure pump under the bonnet was not satisfactory as owing to its increased head due to being mounted higher up it held the frame pumps out of operation. This meant it did all the work and was very noisy. With all the above schemes the critical air temperature at which vapour troubles became noticeable was 32°C. | ||