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).
Instructions for carburettor mixture control, starting procedures, and high-speed jet settings.
| Identifier | ExFiles\Box 13\4\ 04-page036 | |
| Date | 21th September 1932 | |
| -3- Hs{Lord Ernest Hives - Chair}/Swdl.{Len H. Swindell}12/KT.21.9.32. described, the mixture control must be in the "full strong" or starting position. The throttle should be then opened very slightly and when the engine fires the throttle opened a further few notches on the quadrant. This carburetter has a throttle stop fitted and should be adjusted when the engine is warm to "tick over" at 200-250 r.p.m. Future starts from cold are carried out with the throttle on its stop. Failure to start may be caused by :- (a) Throttle too far open. (b) Slow running body (E.52875) and sleeve (E.82875) not being down on the jet seat, this being essential for cold start. (c) Throttle edge plug adjustment which is incorrectly fitted and that there are no air leaks into same. (6) High speed Jet setting. The "mechanical" setting for the high speed jet is with the control in the normal position and the actuating rod adjustment in its midway position. Final adjustment is obtained with the engine thoroughly hot and running light at 1000 r.p.m. With the mixture control in the economical running position, the mixture should be weakened off by the actuating rod until maximum r.p.m. is reached and locked in this position. This setting can be checked, for if the actuating rod be unlocked and set slightly weaker, the speed should begin to fall. (7) Assembly of high speed jet mechanism. The main jet actuating rod (E.83407) must work freely in the actuating rod nut (E.83408) and the latter move freely up and down in its guide. Operated by this is the main jet working lever (E.82841) which should move freely in the slotted bush (E.82842), the latter allowing for full movement of the lever, both rich and weak. The main jet (E.83187) is a sliding fit in its guide (E.83584) and should follow the movement of the jet lever (E.82841) without any sticking. | ||