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).
Letter detailing two engine faults observed during testing: a 'fade away' issue and comparatively low speed.
| Identifier | ExFiles\Box 54\4\ Scan042 | |
| Date | 27th April 1925 | |
| 4647 16, Sutherland Road, PLYMOUTH. April 27th 1925. E.W.Hives Esq, Msrs Rolls-Royce Limited, DERBY. Dear Sir, As I have at long last succeeded in winding up my business affairs I am now free to devote my time to the question of the engine of which you have now for several months had the model in your hands for testing and experimenting with. During the two or three days I spent at the Works in August last there were two particular faults which stood out, viz, that after running for a short time the engine would pull up or, as Mr Warwick termed it, "fade away": this, I am of opinion, was caused by lack of adequate lubrication to the outer wall of the minor diameter piston and it points to the need of a forced feed lubrication combined possibly with a wiper ring at the lower end of the working cylinder. Mr Royce, in fact, at our interview saw quite early that the lubrication of this surface presented a difficulty but you have, no doubt, long ago realized this. The second adverse feature was the comparatively low speed the engine attained and this apparently arose from a throttling action due to inadequate valve opening and as to this quite a lot of the internal fixed sleeve of the valve could be cut away without affecting its functioning and would admit, to some considerable extent, of freer passage without any increase of size. | ||