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).
Technical discussion on valve auto-adjustment mechanisms, clutch jaggers, and crankshaft damper designs.
| Identifier | ExFiles\Box 178\3\ img162 | |
| Date | 10th November 1933 | |
| (2) hottest water. Then bring this oil to fall upon, and run down, the push rods, which we understand are quite correct for expansion if kept the same temperature as the cylinder jackets. I do not now know how difficult it would be to apply auto-adjustment, but we have sent several designs and suggestions to Derby, and asked some questions about these which have produced nothing useful. For instance, we schemed the system of making auto-adjustment a close fit without oil in such a way that there would be only slight extra clearance if it failed, or while it was takingup its clearance. Regarding the pattern (like Cadillac) where the adjustment is on the rocker centre, I could not get anyone to explain how these retrace their adjustment. It may be while the rocker is moving it may carry the eccentric bush with it. One always imagines that the retrace should take place while the cam is on the dwell. Will E.{Mr Elliott - Chief Engineer} try to apply what we have done - i.e. the direct one, and also try an application of the Cadillac scheme. I also understand that the rocker shaft has more flexi than desirable. This is probably a defect in itself, especially at the overhanging ends, but it may be brought about by the high lift, and the very stiff valve springs required. CLUTCH. Clutch jaggers probably are not due at all to rubber coupling, but more likely entirely to the state of the ferodo surface, or the new two step scheme - i.e. the pressure not progressive enough. Rubber parts could be made solid for trial. CRANKSHAFT DAMPER. You will see from my telegram that I am very suspicious that our dampers are not effective: if set up with much friction they fail to slip. When they do slip they exert very little damp-ing friction. We sent from WW. a dry centrifugal one, but it was said not towork. But Chrysler uses a weighted rubber one in a Vee groove which is said to be good. I cannot understand why ours is wrong, if Chrysler is right. I feel there is great advantage in both centrifugal loading and dry friction. (It is now explained that centrifugal loading increases too rapidly, and I therefore suggest half centrifugal, half permanent.) Cont'd.{John DeLooze - Company Secretary} | ||