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).
Private letter discussing recurring failures of Bentley big end bearings and proposing a discretionary inspection policy.
| Identifier | ExFiles\Box 27a\1\ Scan145 | |
| Date | 29th October 1934 | |
| COPY. To Sg.{Arthur F. Sidgreaves - MD} London. Private. Levallois Srl/Crn.29.10.34. re Bentley bearings. Having recently discussed this subject with "Rm{William Robotham - Chief Engineer}", I feel convinced that the time has now come for me to ask you to give a definite ruling on this matter. The position, as you are aware, is as follows:- Bentleys that are driven to "capacity" suffer from cracking up of their big ends after approximately 20,000 miles, and this being the case, I feel certain that you will appreciate the necessity of avoiding any breakdowns that would, without any doubt, be a disaster to us from a commercial point of view, not to mention the technical side. Being fairly well acquainted with these technical difficulties, I appreciate the efforts that are being made to put this matter right, but, in the meantime, I should like you to approve of the following:- That we, over here, should be allowed to use our discretion as to whether or not the bottom half should be removed and the bearings inspected, according to the manner in which we know the car has been driven. I know, quite well, which are the customers who "bat" their cars severely, as apart from those who drive them in a fairly normal manner, and in the latter cases undoubtedly we need have no fear of bearing troubles developing before what it would appear to the customer as a reasonable mileage. On the other hand, the aforementioned owners would probably (especially during the Summer periods) develop cracked big end bearings after 20,000 odd miles. Should you agree that we should use our discretion where this type of customer is concerned, and should we discover upon inspection defective big end bearings, at this moment, upon communicating with your goodself, you could in each particular case give us instructions as to that which should be done, although I take this opportunity of pointing out that there is no possibility that I can see of being able to make a charge to a customer for remedying this trouble, which he will undoubtedly consider to be a defect, although he would probably, in fact almost certainly accept same but reluctantly on other makes of cars. I would not like you to think that I am making an undue fuss about this matter, and looking for trouble, but I can safely state that my experience of the French market is sufficient to enable me to ring an alarm bell in time, when I consider it necessary, and this is a case where there can be no doubt about the necessity arising. Upon suggestions made by "Rm{William Robotham - Chief Engineer}", we dismantled B-5-AE, and the big end bearings were found to be cracked. This car, however, has covered about 32,200 miles, under the very worst possible conditions, viz: demonstrating during the hot periods of the year, and it is | ||