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).
Causes and solutions for oil shortages in hydraulic shock dampers.
| Identifier | ExFiles\Box 68\2\ scan0223 | |
| Date | 14th April 1928 | |
| To Mx.{John H Maddocks - Chief Proving Officer} from Hs{Lord Ernest Hives - Chair}/Rn.{Mr Robinson} c. to EY. X8520 Hs{Lord Ernest Hives - Chair}/Rml/LG14.4.28. HYDRAULIC SHOCK DAMPERS. X235 With reference to MX{John H Maddocks - Chief Proving Officer}7/T12.4.28. We do not consider that the trouble of shortage of oil should be experienced on shock absorbers on test. If it is, it merely means that the shock absorber has been incorrectly filled in the first place. If the high pressure valve cap is removed when the shock absorber is filled and the lever worked up and down as oil is added, it is possible to fill the shock absorber so that there is practically speaking no air left in it. We do not consider that it is desirable to run the shock absorber miles and miles on the road adding a little oil at a time in order to get rid of air which may be eliminated in quite a short time by the correct method of filling. Once the shock absorber has been correctly filled we consider that the air release can satisfactorily deal with the small quantity of air which may collect in the emulsified oil. A month ago we had a note from America saying they recommend increased dia. oil replacing passages with larger balls. We went into the question and found that their reasoning on the subject was quite incorrect and that the present size balls and passages are quite capable of dealing with any replenishment that we have discovered to be necessary. We should be glad, if the next time you get a shock absorber on test which seems to suffer from shortage of oil & a large air content, that you hand it over to us contd:- | ||