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).
Meeting notes discussing valve spring breakages and softness issues.
| Identifier | ExFiles\Box 80\3\ scan0083 | |
| Date | 13th December 1911 | |
| VALVES & VALVE SPRINGS (Contd.) (4) Mr. Johnson asks:- 1. Why the springs broke? 2. Information concerning the tests of this chassis? 3. [Strikethrough] Why the rotor gave trouble? [/Strikethrough] 4. Whether valve springs are likely to give trouble on other cars? The Committee's replies to these questions are:- 1. The breakages are probably due to the increased lift on the new camshaft. 2. Mr. Platford reports that the valve springs gave no trouble on this car during test, and added that he never experienced any trouble with valve springs breaking while cars were on test. These failures generally occurred after at least 700 or 800 miles running. 3. [Strikethrough] This trouble was probably caused by the rotor being inaccurately set, and thus causing considerable sparking. [/Strikethrough] 4. All valve springs fitted to cars with the increased lift on camshaft may give trouble by springs breaking. 98th Meeting Re Valve Springs. Dec. 13. 11. Mr. Platford reported to the Committee that he was now experiencing trouble with [Handwritten: Standard] valve springs being soft, the result was that the spring pressure was reduced, and the valves did not remain closed during their proper periods with a closed throttle. The Committee agreed that it was possible that the spring manufacturers had decreased the hardness | ||