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).
Various component failures during an endurance run.
| Identifier | ExFiles\Box 123\5\ scan0343 | |
| Date | 25th February 1939 | |
| -3- Failures - Cont'd.{John DeLooze - Company Secretary} The collective damper troubles have been reported in our memo Rm{William Robotham - Chief Engineer}/Swdl.{Len H. Swindell}2/MH.{M. Huckerby}1.2.39. In view of the mechanical unreliability of the R.R. damper it was decided to continue with the Studebaker type of damper which has rubber blocks as the damping medium. After a further 34 hours endurance the camwheel again failed in almost identical manner to the first failure, in this case, however, the Studebaker damper was still in the same good condition as when fitted. Continuing to the end of the run with a new camwheel, the inspection reveals that this is still in good condition. The Delco ignition distributor gave a considerable amount of trouble, the condenser failing twice, the contact breaker points having to be reset several times, short circuiting between the contact breaker arms and the distributor body and finally, wear of contact breaker bushes. Regarding the auxilliary drive Ferogrip belt, a failure occurred after 30 hrs. and adjustment of the tension had to be carried out several times during the run. After 6 hours one of the Phantom III outer inlet valve springs S/CV failed and on dismantling an inner spring was also found broken. One pleasing feature of the complete run was the consistency with which the valves maintained their clearance, particularly the exhaust valves. Running with the A.C. mechanical pump, the petrol delivery failed after 30 hours due to wear of the push rod which is actuated from the camshaft eccentric, the latter being in good condition. After 40 hrs. the distributor developed a considerable amount of slack, revealed on dismantling to be the shearing of the pin locating the BZ/PC distributor gear on its shaft. This caused the distributor gear to ride out of mesh with the camshaft gear which in consequence caused considerable wear of the distributor gear. The tappet doors have leaked oil continuously and are not stiff enough for the job as stated in the B.80 report. | ||