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).
Bentley big end bearing failures, attributing them to atmospheric temperature and proposing necessary modifications.
| Identifier | ExFiles\Box 27a\1\ Scan137 | |
| Date | 26th October 1934 | |
| 4013 W/P - Sr. Hs{Lord Ernest Hives - Chair}/Rm.{William Robotham - Chief Engineer}14/KW.26.10.34. Bentley Bearings. Dear Sr., Thank you for your note of the 24th. I discussed the matter with Sg.{Arthur F. Sidgreaves - MD} and Wor.{Arthur Wormald - General Works Manager} to-day and pointed out that the subject was of vital importance as you were in the process of establishing a reputation for the Bentley in France. The result of the discussion was that we are going to urge the necessary bearing modification for all we are worth, and they should be on chassis before next summer. The main point about the big ends cracking up is of course that the controlling factor is the atmospheric temperature. Therefore you can definitely assume that B.5.AE is as bad as any car is likely to be because it has been driven to the limit through one of the hottest summers on record. Furthermore, I believe you have done a number of continuous laps on Montlhery, which produces the worst possible conditions for the bearings. I believe you could have done the same running through the winter and the bearings would have been perfectly all right because the oil temperature would not have been above 100°C. The point of these remarks is that you should not get unduly alarmed. I am in entire agreement, however, that you should put the matter up to Sg.{Arthur F. Sidgreaves - MD} and get his decision on it. I do feel however that rather than put a fixed mileage it would be better to examine the bearings at your discretion i.e., certain drivers would need this inspection at 20,000 miles, others would be quite happy for double the distance. | ||