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).
Advantages of minimizing lubricating grooves in aero and car engines.
| Identifier | ExFiles\Box 72\1\ scan0141 | |
| Date | 3rd March 1928 | |
| E.{Mr Elliott - Chief Engineer} RG.{Mr Rowledge} Hs.{Lord Ernest Hives - Chair} BY.{R.W. Bailey - Chief Engineer} from R.{Sir Henry Royce} +8980 R3/M23. 3. 28. AERO AND CAR ENGINES. X. 2176 LUBRICATING GROOVES. X. 8980 X. 8040 X. 3996. Now we know that engines can run better with much less oil grooves, will all concerned see that we can benefit by this knowledge at once by getting all our engines made in future with the minimum of oil grooves, because : (1) There is less heated oil to cool. (2) There is less oil on pistons. This was the outcome of Col. Fell's impressions that our oil flow was excessive. You will remember that our earlier work was done with less oil grooves because we thought (a long way back) that many of the holes and grooves relieved the oil pressure, and scraped off the oil, and so reduced the load carrying capacity of a bearing. It will also be remembered that increased oil grooves were first tried and thought to be an improvement in the Eagle engine about 1914/15. I cannot understand why we should have gone wrong if it were always right to have less oil-ways, except that we may have been trying too low an oil pressure, or the simple feeds in the wrong place. On all new work going through - i.e. 'SS{S. Smith}' engine, H.{Arthur M. Hanbury - Head Complaints} engine, and current production of Fs.{F. Steele}, Phantoms, and 20 HP., the oil grooves should be left out until the best arrangement has been found by experiments. To the best of my memory E.{Mr Elliott - Chief Engineer} and R.{Sir Henry Royce} have gone over much of the 'SS{S. Smith}' engine. Will RG.{Mr Rowledge} and E.{Mr Elliott - Chief Engineer} give some instructions for Hs.{Lord Ernest Hives - Chair} to test out. My simple rule was feed in by simple hole at point of least bearing pressure. R.{Sir Henry Royce} | ||