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).
Valve spring breakages related to a new camshaft type, proposed testing, and potential replacement.
| Identifier | ExFiles\Box 80\3\ scan0082 | |
| Date | 1st October 1937 | |
| VALVES & VALVE SPRINGS (Contd.) (3) This spring had been replaced with the result that the second spring broke after 700 miles. With reference to the valve spring failures, the Committee have been aware that for some time the fitting of the new type of camshaft increases the risk of breakage of the valve springs, and although the calculated stress is by no means excessive, yet they have considered it advisable to make further investigations concerning the possibility of still further reducing this stress and as previously recorded in the minutes, have ordered one gross of special springs designed on these lines. They proposed to run a test by a special rig which will be equivalent to 10,000 miles on the road. The Committee recommend that owing to the more frequent occurrence of spring breakages, that the whole of the springs at present fitted to engines having the new camshaft, should be replaced by these modified springs if they prove satisfactory by the above tests. Mr. Platford pointed out that the valve springs fitted to the engine with the first of the new type of camshaft had never failed. They had been running continuously ever since the car was built, and had been in use on the demonstration car for a considerable period. The total number of miles run was about 15,000 K.W. 422 (9936) C/P. 10m 10/37 C & Co. Ltd. | ||