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).
Hydraulic damper knocks and test results for various car models.
| Identifier | ExFiles\Box 151\2\ scan0352 | |
| Date | 16th October 1937 | |
| To By. {R.W. Bailey - Chief Engineer} c. to Rm {William Robotham - Chief Engineer} /Les. 1292 Rm {William Robotham - Chief Engineer} /IMW. {Ivan M. Waller - Head of Chateauroux} 3/JH.16.10.37. R.R. Hydraulic Dampers. Replying to Rm. {William Robotham - Chief Engineer} 5/R.14.10.37., last quarters figures from London for internal damper knocks which could not be easily overcome, i.e. by bleeding or adding oil, were as follows - Phantom III. 4 25/30 30 Bentley 5 The experience on 15,000 miles tests is as follows - 35-EX Phantom III - Bad damper knocks from main bushes developed at end of mileage. The damper arms had been changed at Paris half way through the running. 32-EX Phantom III - main bushes reported badly worn at end of mileage. No knocks were reported. This was attributed to the cushioning effect of the special Duprene glands fitted. 22.G.IV. 25/30 - Repeated trouble with bush knocks. This was before diamond boring was used. Bentley. - No trouble with any cars. Rm {William Robotham - Chief Engineer} /IMW. {Ivan M. Waller - Head of Chateauroux} | ||