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 adjustments relating to pilot jets, oil pressure, and extra oil supply.
| Identifier | ExFiles\Box 16\1\ Scan104 | |
| Date | 10th March 1926 | |
| Oy1-E-31026 -3- March 10, 1926 5. Engines consequently cannot be made to knock while the pilot jet and extra oil is in operation. Without going so far as to advocate prolonged use of the pilot jet (which will cause smoking) we believe we should circulate a service bulletin pointing out this important change in starting the cars. We are also setting our pilot jets on the lean side, so that they can be left on for longer periods before smoking or loading up. On a cold morning we think it is quite good practice to run 200 yards or so with the pilot jet operating. 6. Relief valve springs permitting oil pressures up to 50 lbs. will be received on Experimental Order D-3408 within ten days. They will first be tried on demonstrators and cars around the factory. In connection with this oil pump off CX{Major Len W. Cox - Advertising Manager} which has drilled oil feed to bearings should be examined. This has run 17,000 miles. 7. Extra Oil Supply. A slight change is necessary to cranked lever E-26, setting the two parts at 30° instead of 90°, to allow extra oil to come into operation at any stage from just-open to full-open according to requirements. White Sheet was put through for this. This involves no change in the operation except that it permits a wide range of setting as above. We shall then set all new cars to open early, that is within the first half of the throttle opening, in order to avoid present under lubrication trouble. Later (perhaps 5000 miles from now or less if the oil consumption is high), it will be necessary to reset the operation to bring the extra oil in later (say after 2/3 of throttle opening). We think this is by far the best way of dealing with the present trouble. Oy. Maurice Olley MO/E | ||