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).
Analysis of valve sticking due to oil starvation in bearings and the design of a new bush to resolve the issue.
| Identifier | ExFiles\Box 96\2\ scan0180 | |
| Date | 9th December 1936 guessed | |
| (2) When an engine is stopped some of its Valves are in the open position, and in this particular case these are the valves which give the most trouble. This is so because if the engine is left to stand for about twelve hours with the valve spring pressure reaction load on the rocker and eccentric bearings. - - all the oil at the point of contact in the bearing is squeezed out, and the next time that particular Rocker is moved it is noticed that the eccentric arm has been stuck to the Rocker and pulled round with it and then gone back with a click. This has never happened on a valve in the closed position. The next step was to try and keep some oil in the rollers of the bearing. A new bush was designed RM{William Robotham - Chief Engineer} 267 as shown in sketch to maintain a supply of oil inside the bearing which could not be squeezed out and also with an extra .0005" clearance on both diameters to reduce the general oil drag. | ||