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).
Speedometer failures due to incorrect materials and increased spring pressure from the supplier.
| Identifier | ExFiles\Box 165\2\ img012 | |
| Date | 26th January 1937 | |
| 6965 WST. We must find out where bad speedometers BY/RD.2/B.26.1.37. Started to come in and consider retrospective action Rm{William Robotham - Chief Engineer} SPEEDOMETERS. With reference to the trip failures which have been occurring with such regularity, it has now been ascertained that the speedometer makers had increased the spring pressure of the trip mechanism, and also that they had had, delivered to them, rollers manufactured in a wrong alloy, thus causing excessive wear and consequent failure. This was discovered and steps were taken to obtain rollers in the correct material and lighter springs. This modification took place as near as can be ascertained, in the middle of January 1937, and therefore speedometers received after this date should be satisfactory. The A.T.Speedometer Co., are not in position to tell us when the incorrect material was first fitted, but we should anticipate that speedometers manufactured in the latter half of 1936 would be prone to this trouble. We are communicating with the A.T.Speedometer Co., in an attempt to get further information, and we will advise you in due course. In the meantime, any stock that we may have on hand manufactured before the middle of January should be returned for modification, but I believe the position has been 'hand to mouth', and it is not likely that any stock on hand will have occurred. As this affects both Bentley and Rolls-Royce speedometers, will Hd.{Mr Hayward/Mr Huddy}, please advise Kingsbury and Cricklewood accordingly. BY/RD. | ||