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).
Test report on 12 experimental grooved oil pumps, detailing noise levels and remedies when fitted to various chassis.
| Identifier | ExFiles\Box 77\1\ scan0155 | |
| Date | 1st February 1928 | |
| EWC1BZ/1/28 February 1st, 1928. RE OIL PUMPS ( D-3557) Under this experimental order number, 12 oil pumps were produced with covers, A-8068, having slots .375 wide x .075 deep, cut up to the center line of the gears. These special pumps were fitted to the following chassis:- REMARKS CHASSIS SEMI FINAL TEST RUN FINAL TEST RUN 386 FM Quiet Pump OK 387 FM " " OK 388 FM " " OK 389 FM " " OK 390 FM " " OK 391 FM Slightly Noisy OK when gears are reversed 392 FM Quiet Pump OK 393 FM Slightly Noisy Passable 394 FM " " OK when gears were reversed 395 FM Quiet Pump OK 396 FM " " OK 397 FM " " OK The amount of work necessary to make the two noisy pumps satisfactory, consisted in reversing the gears. The standard pump with a plain cover is generally noisy. A fair average would be 4 or 5 quiet pumps out of 12. As regards freedom from noise during test, these twelve grooved pumps are a definite advance over anything so far tested. E.{Mr Elliott - Chief Engineer} W. Caswell | ||