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).
Troubles with large helical oil pumps and proposing design reconsiderations.
| Identifier | ExFiles\Box 149\2\ scan0137 | |
| Date | 9th February 1937 | |
| Hs.{Lord Ernest Hives - Chair} from Rm.{William Robotham - Chief Engineer} By.{R.W. Bailey - Chief Engineer} RHC.{R. H. Coverley - Production Engineer} Is. 126/S LARGE OIL PUMPS. We are now able to release the large helical oil pumps. As will be seen from the attached report, the trouble was finally traced down to the annular clearance on the bronze bush which is fitted in the aluminium case, causing a leak from the suction to the delivery side of the pump. The attached memo gives our recommendation for overcoming this trouble, the suggestions being the result of discussing the matter with the production people concerned. We think that now fine limits are involved, the manufacture of our oil pumps ought to be re-considered to see whether a die cast aluminium bronze case would not reduce the cost considerably. As a general result of oil pump investigation, we have come to the conclusion that if we were less keen on our oil pump capacities, we should not be so dependent on fine limits, nor should we be so sensitive to main bearing wear. We, therefore, asked S. to look into the question of stepping up pump sizes with relieve valves to suit on all cars. Troubles have, of course, been accentuated due to our determination to use thin oil, and the necessity for increased delivery to the big-ends. Rm.{William Robotham - Chief Engineer} | ||