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).
Engine performance, detailing issues with oil consumption, pressure, starting, and tappets.
| Identifier | ExFiles\Box 91\1\ scan0387 | |
| Date | 14th August 1936 guessed | |
| -2- Engine. Power and acceleration were well maintained throughout the mileage, it has been smooth and run without any signs of a period at any time. After a mileage of 2,000 there were definite signs of overoiling after a period of idling. Subsequently this developed and clouds of light blue smoke would deluge out from the exhaust, on a getaway in traffic. The oil consumption has been pretty well constant but the consumption very rarely exceeded 1,000 miles/gallon. Considerable quantities of oil were lost through oil leaks during the former part of the mileage, but did not make an appreciable difference in the consumption. We have kept a careful check on the oil pressure throughout, taking four readings a day at 100°C. at speeds of 70 M.P.H. and at 10 M.P.H. A constant pressure of 30 lbs. was recorded at the higher speed, while never more than 3 lbs. could be obtained at the lower speed. We noticed that the oil pressure would fall off on left hand corners, and dropped on an average by 10 lbs. but would soon recover itself on straightening out. We think that a revision of the sump baffles should be made in order to counteract this tendency. The engine would start well from cold, provided the controls were set correctly, but we had some difficulty in starting up under extremely hot conditions; we deal with this in a later report. Silent tappets have given us no trouble throughout, apart from a slight audible click from time to time, but this was automatically cured as soon as the tappet filter was cleared of sludge. At no time have we touched the tappets or plungers with depressing wires etc., as had to be done on the previous cars. The tappet covers are satisfactory and the new method of bolting them down by 1/4" nuts obviates all leaks. We have found no traces of oil in the clutch pit, which have come from No.7 bearing. The oil retaining scheme is 100% and calls for no criticisms. | ||