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).
Notes on valve noise, camshaft stoning, valve springs, camshaft pitting, exhaust manifolds, and oil temperature control.
| Identifier | ExFiles\Box 126\4\ scan0124 | |
| Date | 2nd May 1936 | |
| -4- (6) Cont'd.{John DeLooze - Company Secretary} They said that they had one valve which was always noisy and no amount of calculation on the camshaft put it right. However, they found that by stoning the camshaft they could get a form which silenced the valve and this was reproduced on the master cam. It is rather interesting as indicating one way of tackling the problem. They managed to effect a great improvement in valve springs by shot-blasting the surface of the spring. This work-hardens the surface and is more economical than grinding, etc. We are going to try and follow this up. They have found that a small proportion of lard oil in the engine has a great effect in preventing camshaft pitting. They run their valves somewhere about 55/60 lbs. seat pressure. (7) Whyman. Taub said the best exhaust manifold he had seen was that on the Oldsmobile. We should have a look at this and see what its merits are. (8) Grylls. Steadman. Taub said that by dropping the water jackets to the bottom of the cylinder barrel, they decreased the oil temperature by 40°C. They now run with a maximum oil temperature of 260°F.{Mr Friese} inlet to the bearings. We ought to make an experiment to see if we can do this on the Bentley. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||