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).
Engine noises ('chunking'), exhaust valve weaknesses, and future car redesigns.
| Identifier | ExFiles\Box 1\4\ B001_X 100a-page121 | |
| Date | 8th December 1932 | |
| -2- Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}10/MJ.8.12.32. Cont'd.{John DeLooze - Company Secretary} exactly where the 'chunking' comes from. We have been making comparative tests with 1 Per., 3 Per., and 18-G4. We find that 1 Per. and 18-G4. have a similar 'chunking' except that the foremost seems to have a little more slack in the back axle and consequently makes the most noise. 3 Per. on the other hand has an additional clanking which seems to come from the neighbourhood of the gearbox. You might let us know whether if you get your car to run evenly on all six cylinders the noise is tolerable. (7) Exhaust Valves. We have now definitely established a weakness in the exhaust valves. After continuous full throttle running we have had another failure, smashing the piston cylinder liner and connecting rod. When we stripped the engine we found another exhaust valve cracked across the neck. We suggest that you examine your exhaust valves carefully to see if there are any signs of failure, so that you can avoid being stranded. We anticipate that if you do not often run above 4500 revs., which on your car is 75 M.P.H., you are fairly safe. We should like you to let us know what arrangements you are making for returning. It would appear that the next car you take out will still not be the final one because we have had to completely redesign the carburetter and drop the steering box. However, it will be much better than anything you have previously had. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer} | ||