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).
Solutions for piston knock issues, focusing on engine oiling systems and extra lubrication during starting.
| Identifier | Morton\M22\ img046 | |
| Date | 21th August 1919 | |
| PISTON KNOCKS & OILING MAINLY / EX To EH. from R.{Sir Henry Royce} -2- R3/G21.8.19 crankchamber has oil of sufficient body, we would like the surfaces of the pistons to become oiled before the engine is put under load. I believe that if we could do this, much of the trouble of piston knocks would disappear. I remember it is usual for us to recommend that the extra oil valve be pressed down during starting, but as far as myself and other people are concerned, we do not follow this practice, being too much trouble. It might be possible, however, to arrange this to be done magnetically with the starter button, though I fear the period on which the starter is on is too short. Something based on this idea may, however, be forthcoming, if we find that the piston knocks can be cured by extra lubrication at the time needed. Mr. Elliott suggests that we may still be using the baffles, but I cannot think this possible, since we have such a clear view that the over-lubrication can be better dealt with by scraper rings. We have long ago endeavoured to find a piston that is capable of being smothered with ample lubricating oil without fear of it working into the combustion chamber. If we can do so, it may be that we shall be wise in providing a low pressure oil system which is always supplying oil to the pistons, and that it would give an ample supply with thick oil and close fitting bearings, without robbing the bearings of their pressure. Also, a long time ago we drew a distributor giving a fixed quantity of oil per revolution to each of the cylinders in Contd. | ||